Synthesis of E, E-dibenzalacetone (E, E-DBA) Lab ReportN.docx
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About This Presentation
Synthesis of E, E-dibenzalacetone (E, E-DBA) Lab Report
Name
Institution
Course
Instructor
Date
Abstract
The main purpose behind this experiment was to synthesize E, E-dibenzalacentone by use of a based-catalyzed aldol condensation reaction. Secondly, this experiment was aimed at identif...
Slide Content
Synthesis of E, E-dibenzalacetone (E, E-DBA) Lab Report
Name
Institution
Course
Instructor
Date
Abstract
The main purpose behind this experiment was to synthesize E,
E-dibenzalacentone by use of a based-catalyzed aldol
condensation reaction. Secondly, this experiment was aimed at
identifying characteristics of crude and purified samples of E,
E-dibenzalacentone by use of the melting point determination
method. The results from this experiments showed that the
synthesis process yielded 65% crude E, E-dibenzalacentone and
56% yield for purified E, E-dibenzalacentone. When it comes to
the techniques that were used, the researchers employed Hirsch
funnel and solid-liquid extraction as part of the separation
techniques. Lastly, recrystallization of the E, E-
dibenzalacentone was also used as a purification technique.
Introduction
Name
Institution
Course
Instructor
Date
Abstract
The main purpose behind this experiment was to synthesize E,
E-dibenzalacentone by use of a based-catalyzed aldol
condensation reaction. Secondly, this experiment was aimed at
identifying characteristics of crude and purified samples of E,
E-dibenzalacentone by use of the melting point determination
method. The results from this experiments showed that the
synthesis process yielded 65% crude E, E-dibenzalacentone and
56% yield for purified E, E-dibenzalacentone. When it comes to
the techniques that were used, the researchers employed Hirsch
funnel and solid-liquid extraction as part of the separation
techniques. Lastly, recrystallization of the E, E-
dibenzalacentone was also used as a purification technique.
Introduction
The synthetic goal of this experiment was to make use of a
based-catalyzed aldol condensation in the entire process of
synthesizing o E, E-dibenzalacentone. The other main goal of
this experiment was to identify or to characterize crude and
purified samples of E, E-dibenzalacentone by use of the melting
point determination
Results
The results of the synthesis of E, E-dibenzalacentone are
summarized below
Compound
Molar mass(g/mol)
Volume/mass moles
Yield
Mp( °c)
Benzaldehyde (density1.043g/mL)
106.2 g/mol
0.250 mL
0.26 g
0.002 mol
N/A
N/A
Acetone(density 0.788g/mL)
58.08 g/mol
0.1 mL
0.07g
0.001 mol
N/A
N/A
E,E-DBA(a yellow solid)
234.24 g/mol
N/A
Theoretical
0.234g
0.001 moles
Literature Value
based-catalyzed aldol condensation in the entire process of
synthesizing o E, E-dibenzalacentone. The other main goal of
this experiment was to identify or to characterize crude and
purified samples of E, E-dibenzalacentone by use of the melting
point determination
Results
The results of the synthesis of E, E-dibenzalacentone are
summarized below
Compound
Molar mass(g/mol)
Volume/mass moles
Yield
Mp( °c)
Benzaldehyde (density1.043g/mL)
106.2 g/mol
0.250 mL
0.26 g
0.002 mol
N/A
N/A
Acetone(density 0.788g/mL)
58.08 g/mol
0.1 mL
0.07g
0.001 mol
N/A
N/A
E,E-DBA(a yellow solid)
234.24 g/mol
N/A
Theoretical
0.234g
0.001 moles
Literature Value
110-111 °c
E,E-DBA(a yellow solid)
234.24 g/mol
N/A
Actual
Crude: 0.65 g=65%
Purified:0.15 g=56%
Actual
101-103Co
Crude
108-109Co
Discussion
The E, E-dibenzalacentone was prepared by combining 0.250
mL of Benzaldehyde, 0.1mL of reaction grade acetone, 0.5 mL
of 95% ethanol and 1 mL of a catalyst solution in a 10 mL
round bottom flask. The catalyst solution that was used in this
experiment has been prepared earlier by dissolving 10g of
sodium hydroxide in 100 mL of water and 75 mL of 95%
ethanol. The main purpose of this catalyst was to speed up
the reaction process. A micro scale condenser was attached to
the round bottom flask and the reactants were gently mixed for
about 15 minutes, until a solid started forming. Then the crude
solid was isolated by pouring the mixture into a Hirsch funnel
attached to the vacuum filter, thus allowing the solid crude E,
E-dibenzalacentone to be trapped by the filter paper in the
Hirsch funnel.
An RB flask was de-attached from the condenser after which it
was rinsed with 20 mL of de-ionized water at one time, 3 times
totaling 60 mL, to gain any residue thus E, E- dibenzalacentone
was left in the round bottom flask. The dried solid was
transferred to a pre-weighed Erlenmeyer flask where its mass
was measured and the results were 0.65 g=65%. A small sample
of the crude solid was taken and smeared on a microscope slide
by use of the flat end of the micro spatula after which a melting
E,E-DBA(a yellow solid)
234.24 g/mol
N/A
Actual
Crude: 0.65 g=65%
Purified:0.15 g=56%
Actual
101-103Co
Crude
108-109Co
Discussion
The E, E-dibenzalacentone was prepared by combining 0.250
mL of Benzaldehyde, 0.1mL of reaction grade acetone, 0.5 mL
of 95% ethanol and 1 mL of a catalyst solution in a 10 mL
round bottom flask. The catalyst solution that was used in this
experiment has been prepared earlier by dissolving 10g of
sodium hydroxide in 100 mL of water and 75 mL of 95%
ethanol. The main purpose of this catalyst was to speed up
the reaction process. A micro scale condenser was attached to
the round bottom flask and the reactants were gently mixed for
about 15 minutes, until a solid started forming. Then the crude
solid was isolated by pouring the mixture into a Hirsch funnel
attached to the vacuum filter, thus allowing the solid crude E,
E-dibenzalacentone to be trapped by the filter paper in the
Hirsch funnel.
An RB flask was de-attached from the condenser after which it
was rinsed with 20 mL of de-ionized water at one time, 3 times
totaling 60 mL, to gain any residue thus E, E- dibenzalacentone
was left in the round bottom flask. The dried solid was
transferred to a pre-weighed Erlenmeyer flask where its mass
was measured and the results were 0.65 g=65%. A small sample
of the crude solid was taken and smeared on a microscope slide
by use of the flat end of the micro spatula after which a melting
point capillary tube was used to get approximately 2mm of
crude product. A Mel-Temp device was used to find out the
melting point of the crude product 108-109Co
The crude product was purified using recrystallization
methods. The solubility of E, E- dibenzalacentone in ethanol at
78 is 0.4g/1mL. Based on my 0.39g, this ratio was used to
determine that 0.985 mL of 95% ethanol should be used. The
solution was heated in a fume hood until the sample was
dissolved, and then cooled at room temperature upon which it
was placed in an ice bath to produce maximum crystals. Steps
were taken to filter the solid with a Hirsch funnel, and then
weighed to produce 0.07 g of purified E, E-
dibenzalacentone. Although a significant amount of product was
lost, it is likely that a lot of the loss was impurities, and after
the melting point was later taken, it was found that the amount
of purified E, E- dibenzalacentone was pure. The dried, purified
product was removed from the Hirsch funnel and its mass was
taken and recorded before its purity was assessed.
Experimental Procedure
The preparation was carried out according to the prescribed
method.
Abstract (~5%)
State briefly the purpose of the experiment, the principal
results, the mode(s) of isolation, separation and purification (as
appropriate) and the major conclusions. You may refer to
schemes and tables found in the introduction, results and
discussion sections by number.
Introduction (~5%)
State clearly the synthetic goal of the experiment. Do not begin
your report with a lengthy description of background theory.
The time to demonstrate your knowledge of background theory
is in explaining the results you have obtained. One or two
paragraphs should be adequate. Include the appropriate balanced
crude product. A Mel-Temp device was used to find out the
melting point of the crude product 108-109Co
The crude product was purified using recrystallization
methods. The solubility of E, E- dibenzalacentone in ethanol at
78 is 0.4g/1mL. Based on my 0.39g, this ratio was used to
determine that 0.985 mL of 95% ethanol should be used. The
solution was heated in a fume hood until the sample was
dissolved, and then cooled at room temperature upon which it
was placed in an ice bath to produce maximum crystals. Steps
were taken to filter the solid with a Hirsch funnel, and then
weighed to produce 0.07 g of purified E, E-
dibenzalacentone. Although a significant amount of product was
lost, it is likely that a lot of the loss was impurities, and after
the melting point was later taken, it was found that the amount
of purified E, E- dibenzalacentone was pure. The dried, purified
product was removed from the Hirsch funnel and its mass was
taken and recorded before its purity was assessed.
Experimental Procedure
The preparation was carried out according to the prescribed
method.
Abstract (~5%)
State briefly the purpose of the experiment, the principal
results, the mode(s) of isolation, separation and purification (as
appropriate) and the major conclusions. You may refer to
schemes and tables found in the introduction, results and
discussion sections by number.
Introduction (~5%)
State clearly the synthetic goal of the experiment. Do not begin
your report with a lengthy description of background theory.
The time to demonstrate your knowledge of background theory
is in explaining the results you have obtained. One or two
paragraphs should be adequate. Include the appropriate balanced
chemical equation(s) (including structural drawings for all
organic reactants and products, inorganic reagents above the
arrows, and solvents and conditions below the arrows) labeled
as Scheme 1. See Scheme 1 of the sample formal report.
Results
The results of the synthesis of Z--phenylcinnamic acid and E-
-phenylcinnamic acid are summarized in Table 1.
108-109Co
101-103Co
0.15g
56%
0.67g
65%
580.08 g/mole
106.2 g/mole
0.25 ml
0.26 g
0.002 moles
0.1 ml
0.07g
0.001 moles
0.234g
0.001 moles
234.24 g/mole
234.24 g/mole
Discussion (~50%)
organic reactants and products, inorganic reagents above the
arrows, and solvents and conditions below the arrows) labeled
as Scheme 1. See Scheme 1 of the sample formal report.
Results
The results of the synthesis of Z--phenylcinnamic acid and E-
-phenylcinnamic acid are summarized in Table 1.
108-109Co
101-103Co
0.15g
56%
0.67g
65%
580.08 g/mole
106.2 g/mole
0.25 ml
0.26 g
0.002 moles
0.1 ml
0.07g
0.001 moles
0.234g
0.001 moles
234.24 g/mole
234.24 g/mole
Discussion (~50%)
A separate paragraph should be included for each one of the
following items: -a written account of how the product was
prepared (i.e. a description of the chemistry involved) along
with appropriate references to any balanced reaction equations
given elsewhere (e.g. in the introduction)
-a written account of how the crude product was isolated
(include chemistry if appropriate)
-a written account of how the crude product was identified,
wherein you cite and interpret relevant experimental data
making reference to appropriate literature data
-a written account of how the crude product was purified and an
evaluation of the efficiency of the purification, wherein you cite
and interpret relevant experimental data making reference to
appropriate literature data
-a written account of how the purified product was identified,
wherein you cite and interpret relevant experimental data
making reference to appropriate literature data
-a discussion of yields
Please remember, we are looking for an account of the results
you obtained and the conclusions that you drew from them.
Experimental Procedure (~2%) Do not copy out the complete
experimental procedure from the manual. “The preparation was
carried out according to the prescribed method” will be
sufficient in many instances.
Page 1 of 6
Lab
Instructions
following items: -a written account of how the product was
prepared (i.e. a description of the chemistry involved) along
with appropriate references to any balanced reaction equations
given elsewhere (e.g. in the introduction)
-a written account of how the crude product was isolated
(include chemistry if appropriate)
-a written account of how the crude product was identified,
wherein you cite and interpret relevant experimental data
making reference to appropriate literature data
-a written account of how the crude product was purified and an
evaluation of the efficiency of the purification, wherein you cite
and interpret relevant experimental data making reference to
appropriate literature data
-a written account of how the purified product was identified,
wherein you cite and interpret relevant experimental data
making reference to appropriate literature data
-a discussion of yields
Please remember, we are looking for an account of the results
you obtained and the conclusions that you drew from them.
Experimental Procedure (~2%) Do not copy out the complete
experimental procedure from the manual. “The preparation was
carried out according to the prescribed method” will be
sufficient in many instances.
Page 1 of 6
Lab
Instructions
Chemistry 337
Unit 5 Synthesis of E,E-dibenzalacetone (E,E-DBA)
INTRODUCTION
The centerpiece of this unit is the synthesis of E,E-
dibenzalacetone (E,E-DBA) for which we will employ a base-
catalyzed aldol
condensation. The crude product will be purified by
recrystallization. The crude and purified products will be
characterized by
melting point determination.
PURPOSE
To employ a based-catalyzed aldol condensation in the
synthesize of E,E-dibenzalacetone
To characterize the crude and purified samples of E,E-
dibenzalacetone by melting point determination
REACTION SCHEME
H
O O
CH3CH3
O
Unit 5 Synthesis of E,E-dibenzalacetone (E,E-DBA)
INTRODUCTION
The centerpiece of this unit is the synthesis of E,E-
dibenzalacetone (E,E-DBA) for which we will employ a base-
catalyzed aldol
condensation. The crude product will be purified by
recrystallization. The crude and purified products will be
characterized by
melting point determination.
PURPOSE
To employ a based-catalyzed aldol condensation in the
synthesize of E,E-dibenzalacetone
To characterize the crude and purified samples of E,E-
dibenzalacetone by melting point determination
REACTION SCHEME
H
O O
CH3CH3
O
NaOH, H2O, ethanol
Benzaldehyde Acetone E,E-dibenzalacetone
2
GENERAL COMMENTS
This comments segment need not appear in your prelab
assignment.
Students will work individually. Other than the
recrystallization all worked described below will be completed
at your lab
bench. The recrystallization will be performed in one of the
fumehoods under the supervision of a TA.
The Unit 5 Fumehood is equipped with dispensing pipettes, for
delivering benzaldehyde and reagent grade acetone, a
burette for dispensing the catalyst solution, several bottles of
95% ethanol, a squeeze bottle of wash grade acetone, a solid
waste container (typically a glass tray), a waste pipette
container, an aqueous waste container (typically a large, wide-
mouthed plastic bottle), and an organic waste container
(typically a large plastic bottle with a red flip-lid).
Disposable gloves, sample vials, Pasteur pipettes, black
threaded caps, O-rings, full plastic septa, creased weighing
papers,
boiling stones and Hirsch funnel filter papers are available on
the front benches.
Benzaldehyde Acetone E,E-dibenzalacetone
2
GENERAL COMMENTS
This comments segment need not appear in your prelab
assignment.
Students will work individually. Other than the
recrystallization all worked described below will be completed
at your lab
bench. The recrystallization will be performed in one of the
fumehoods under the supervision of a TA.
The Unit 5 Fumehood is equipped with dispensing pipettes, for
delivering benzaldehyde and reagent grade acetone, a
burette for dispensing the catalyst solution, several bottles of
95% ethanol, a squeeze bottle of wash grade acetone, a solid
waste container (typically a glass tray), a waste pipette
container, an aqueous waste container (typically a large, wide-
mouthed plastic bottle), and an organic waste container
(typically a large plastic bottle with a red flip-lid).
Disposable gloves, sample vials, Pasteur pipettes, black
threaded caps, O-rings, full plastic septa, creased weighing
papers,
boiling stones and Hirsch funnel filter papers are available on
the front benches.
Metal clamps and thermometer clamps are available in bins
located on the front bench nearest the lab door.
PRELAB ASSIGNMENT TO BE COMPLETED BEFORE YOUR
SCHEDULED UNIT 5 LAB SESSION
Please follow the format used for the Unit 2 prelab assignment.
It is not necessary to repeat steps involving equipment used in a
prior Unit. Just note the number of the page in your lab
notebook where this information is provided.
It is not necessary to repeat “Physical constants and properties”
for reagents, reactants and products encountered in a prior
Unit. Just note the number of the page in your lab notebook
where this information is provided.
Page 2 of 6
It is not necessary to repeat “Chemical hazards and
precautionary measures” for reagents, reactants and products
encountered in a prior Unit. Just note the number of the page in
your lab notebook where this information is provided.
LIST OF CHEMICALS/CHEMICAL HAZARDS AND
PRECAUTIONARY MEASURES/SUPPLEMENTARY LAB
EQUIPMENT
located on the front bench nearest the lab door.
PRELAB ASSIGNMENT TO BE COMPLETED BEFORE YOUR
SCHEDULED UNIT 5 LAB SESSION
Please follow the format used for the Unit 2 prelab assignment.
It is not necessary to repeat steps involving equipment used in a
prior Unit. Just note the number of the page in your lab
notebook where this information is provided.
It is not necessary to repeat “Physical constants and properties”
for reagents, reactants and products encountered in a prior
Unit. Just note the number of the page in your lab notebook
where this information is provided.
Page 2 of 6
It is not necessary to repeat “Chemical hazards and
precautionary measures” for reagents, reactants and products
encountered in a prior Unit. Just note the number of the page in
your lab notebook where this information is provided.
LIST OF CHEMICALS/CHEMICAL HAZARDS AND
PRECAUTIONARY MEASURES/SUPPLEMENTARY LAB
EQUIPMENT
List of chemicals
Acetone
Benzaldehyde
E,E-dibenzalacetone
Ethanol
Ethanolic sodium hydroxide (1.4 M) (as a solution in water and
ethanol)
Chemical hazards/precautionary measures
Acetone, ethanol and benzaldehyde are irritants - handle with
care. Avoid inhalation and skin contact (wear gloves). Avoid
eye contact (wear safety goggles). Notify the instructor
immediately should you spill either of these materials on
yourself or
the lab bench. Ethanolic sodium hydroxide (1.4 M) is corrosive
and causes burns – handle with care. Avoid inhalation and
skin contact (wear gloves). Avoid eye contact (wear safety
goggles). Notify the instructor immediately should you spill
any of
this material on yourself or the lab bench.
Supplementary lab equipment from the Issue Room
None required.
CLEANING GUIDELINES
These guidelines need not appear in your prelab assignment.
You will be using wash acetone to clean lab glassware and
equipment. Since acetone is such a good cleaning solvent only
minimal amounts are required. It is provided in plastic bottles
fitted with red caps having curved tips. The bottles are located
in the fumehoods next to the organic waster containers.
Cleaning locker items
Acetone
Benzaldehyde
E,E-dibenzalacetone
Ethanol
Ethanolic sodium hydroxide (1.4 M) (as a solution in water and
ethanol)
Chemical hazards/precautionary measures
Acetone, ethanol and benzaldehyde are irritants - handle with
care. Avoid inhalation and skin contact (wear gloves). Avoid
eye contact (wear safety goggles). Notify the instructor
immediately should you spill either of these materials on
yourself or
the lab bench. Ethanolic sodium hydroxide (1.4 M) is corrosive
and causes burns – handle with care. Avoid inhalation and
skin contact (wear gloves). Avoid eye contact (wear safety
goggles). Notify the instructor immediately should you spill
any of
this material on yourself or the lab bench.
Supplementary lab equipment from the Issue Room
None required.
CLEANING GUIDELINES
These guidelines need not appear in your prelab assignment.
You will be using wash acetone to clean lab glassware and
equipment. Since acetone is such a good cleaning solvent only
minimal amounts are required. It is provided in plastic bottles
fitted with red caps having curved tips. The bottles are located
in the fumehoods next to the organic waster containers.
Cleaning locker items
For container type items (e.g. beakers, conical vials, flasks,
graduated cylinders, jars, round bottom flasks and test tubes)
add
2 or 3 short squirts of wash acetone then swirl to
dislodge/dissolve any noticeable organics. Finally pour the
contents into an
organic waste container. For all other items direct 2 or 3 short
squirts of wash acetone through/over the item directly into an
organic waste container. If noticeable organics still remain
please speak with your lab instructor.
Cleaning items signed out from the Issue Room
Since these are generally larger than locker items you will need
to use a bit more wash acetone. For container type items use
6 or 8 short squirts of wash acetone. For all other items direct 6
or 8 short squirts of wash acetone through/over the item
directly into an organic waste container. If noticeable organics
still remain please speak with your lab instructor.
Page 3 of 6
TABLE OF REACTANTS AND PRODUCTS
Include the following table in your prelab assignment.
Complete the first three rows as part of your prelab assignment.
reactant/product molar mass volume, mass, moles yield melting
point
graduated cylinders, jars, round bottom flasks and test tubes)
add
2 or 3 short squirts of wash acetone then swirl to
dislodge/dissolve any noticeable organics. Finally pour the
contents into an
organic waste container. For all other items direct 2 or 3 short
squirts of wash acetone through/over the item directly into an
organic waste container. If noticeable organics still remain
please speak with your lab instructor.
Cleaning items signed out from the Issue Room
Since these are generally larger than locker items you will need
to use a bit more wash acetone. For container type items use
6 or 8 short squirts of wash acetone. For all other items direct 6
or 8 short squirts of wash acetone through/over the item
directly into an organic waste container. If noticeable organics
still remain please speak with your lab instructor.
Page 3 of 6
TABLE OF REACTANTS AND PRODUCTS
Include the following table in your prelab assignment.
Complete the first three rows as part of your prelab assignment.
reactant/product molar mass volume, mass, moles yield melting
point
benzaldehyde
(density 1.043 g/mL) g/mole
mL
g
moles
acetone
(density 0.788 g/mL) g/mole
mL
g
moles
E,E-DBA
(a yellow solid) g/mole
Theoretical
g
moles
(density 1.043 g/mL) g/mole
mL
g
moles
acetone
(density 0.788 g/mL) g/mole
mL
g
moles
E,E-DBA
(a yellow solid) g/mole
Theoretical
g
moles
Literature value
110-111oC
E,E-DBA
(a yellow solid) g/mole
Actual
crude*
g
%
purified**
g
%
Actual
crude
purified
110-111oC
E,E-DBA
(a yellow solid) g/mole
Actual
crude*
g
%
purified**
g
%
Actual
crude
purified
* appearance ** appearance
Page 4 of 6
EXPERIMENTAL PROCEDURES
STEP 1 Preparation of E,E-dibenzalacetone (performed at your
lab bench)
a. Fit the bottom end of a microscale condenser first with a
black threaded cap followed by an O-ring.
The O-ring needs to be positioned just above the ground-glass
joint. Affix a black threaded cap,
fitted with a full plastic septum, to the top end of the condenser.
b. After obtaining 0.250 mL of benzaldehyde from the instructor
use the dispensing pipettes/burettes in
the Unit 5 Fumehood to transfer 0.100 mL of reagent grade
acetone, 0.5 mL of 95% ethanol and 1
mL of the catalyst solution to a 10 mL RB flask. The technical
staff prepared the catalyst solution by
dissolving 10 g of sodium hydroxide in 100 mL of water and 75
mL of 95% ethanol.
c. Fit the RB flask with the condenser. Secure the connection
by firmly threading the black cap onto the
Page 4 of 6
EXPERIMENTAL PROCEDURES
STEP 1 Preparation of E,E-dibenzalacetone (performed at your
lab bench)
a. Fit the bottom end of a microscale condenser first with a
black threaded cap followed by an O-ring.
The O-ring needs to be positioned just above the ground-glass
joint. Affix a black threaded cap,
fitted with a full plastic septum, to the top end of the condenser.
b. After obtaining 0.250 mL of benzaldehyde from the instructor
use the dispensing pipettes/burettes in
the Unit 5 Fumehood to transfer 0.100 mL of reagent grade
acetone, 0.5 mL of 95% ethanol and 1
mL of the catalyst solution to a 10 mL RB flask. The technical
staff prepared the catalyst solution by
dissolving 10 g of sodium hydroxide in 100 mL of water and 75
mL of 95% ethanol.
c. Fit the RB flask with the condenser. Secure the connection
by firmly threading the black cap onto the
RB flask in the manner employed in Unit 2.
d. Hold the apparatus by the RB flask and gently swirl its
contents for 15 minutes. Set the apparatus in a large beaker (as
shown in Figure 1) while setting up the equipment depicted in
Figure 2.
STEP 2 Collection of the crude E,E-dibenzalacetone by vacuum
filtration (performed at your lab bench)
a. Using a metal clamp secure a 250 mL filter flask to the left
most vertical support bar. Fit the filter flask with a Hirsch
funnel equipped with a Hirsch funnel filter paper. Connect the
quick-fit adapters of the vacuum trap and filter flask. Your
apparatus should now resemble Figure 2.
b. Prepare to collect the crystals by wetting the filter paper on
the funnel with a little de-
ionized water and applying full suction (using the house vacuum
line).
c. Transfer 60 mL of de-ionized water to a 100 mL graduated
cylinder.
d. Transfer approximately 5 mL of de-ionized water from the
graduated cylinder to the
RB flask through the air condenser then gently swirl to suspend
the crystalline
material. Remove the air condenser and pour the suspension
d. Hold the apparatus by the RB flask and gently swirl its
contents for 15 minutes. Set the apparatus in a large beaker (as
shown in Figure 1) while setting up the equipment depicted in
Figure 2.
STEP 2 Collection of the crude E,E-dibenzalacetone by vacuum
filtration (performed at your lab bench)
a. Using a metal clamp secure a 250 mL filter flask to the left
most vertical support bar. Fit the filter flask with a Hirsch
funnel equipped with a Hirsch funnel filter paper. Connect the
quick-fit adapters of the vacuum trap and filter flask. Your
apparatus should now resemble Figure 2.
b. Prepare to collect the crystals by wetting the filter paper on
the funnel with a little de-
ionized water and applying full suction (using the house vacuum
line).
c. Transfer 60 mL of de-ionized water to a 100 mL graduated
cylinder.
d. Transfer approximately 5 mL of de-ionized water from the
graduated cylinder to the
RB flask through the air condenser then gently swirl to suspend
the crystalline
material. Remove the air condenser and pour the suspension
into the Hirsch funnel.
Re-attach the air condenser.
e. Repeat Step 2d three times.
f. Gently score the crystalline material with a microspatula.
g. Pour approximately 20 mL of the remaining de-ionized water
from the graduated cylinder into the Hirsch funnel. Gently
score the crystalline material with a microspatula.
h. Pour the remainder of the de-ionized water (~20 mL) from
the graduated cylinder into the Hirsch funnel. Gently score the
crystalline material with a microspatula.
i. To facilitate the recrystallization to follow it is necessary to
dry the solid by continued suction for 5 minutes while
proceeding with other work.
j. While the drying under suction is underway transfer 6 mL of
95% ethanol to a large test tube. Place the test tube in a
beaker of ice and water (replenish ice and water as needed).
This chilled 95% ethanol will be used in Step 4.
k. Clean the 10 mL RB flask, condenser and microspatula with
wash grade acetone.
l. Carefully disconnect the quick-fit adapters of the vacuum trap
and the filter flask then turn off the house vacuum line.
m. At your lab bench place a pre-weighed 10 mL Erlenmeyer
flask on a piece of creased weighing paper. Using a
Re-attach the air condenser.
e. Repeat Step 2d three times.
f. Gently score the crystalline material with a microspatula.
g. Pour approximately 20 mL of the remaining de-ionized water
from the graduated cylinder into the Hirsch funnel. Gently
score the crystalline material with a microspatula.
h. Pour the remainder of the de-ionized water (~20 mL) from
the graduated cylinder into the Hirsch funnel. Gently score the
crystalline material with a microspatula.
i. To facilitate the recrystallization to follow it is necessary to
dry the solid by continued suction for 5 minutes while
proceeding with other work.
j. While the drying under suction is underway transfer 6 mL of
95% ethanol to a large test tube. Place the test tube in a
beaker of ice and water (replenish ice and water as needed).
This chilled 95% ethanol will be used in Step 4.
k. Clean the 10 mL RB flask, condenser and microspatula with
wash grade acetone.
l. Carefully disconnect the quick-fit adapters of the vacuum trap
and the filter flask then turn off the house vacuum line.
m. At your lab bench place a pre-weighed 10 mL Erlenmeyer
flask on a piece of creased weighing paper. Using a
microspatula carefully transfer the crude E,E-dibenzalacetone
from the Hirsch funnel directly into the Erlenmeyer flask
(the creased weighing paper is used solely to contain any spilled
material). Transfer any spilled material to the flask.
Reweigh the flask and determine the mass of the crude E,E-
dibenzalacetone. Retain a small sample of the crude E,E-
dibenzalacetone (about the size of a grain of uncooked rice) in a
small test tube for a melting point determination next
week.
Page 5 of 6
n. Discard the filter paper and weighing paper in the appropriate
solid waste container.
o. Discard the filtrate in the appropriate aqueous waste
container. Clean the filter flask, microspatula and Hirsch
funnel
with wash grade acetone.
STEP 3 Purification of the E,E-dibenzalacetone by
recrystallization (performed in the designated fumehood)
a. Transfer an appropriate volume of 95% ethanol to the 10 mL
Erlenmeyer flask containing your crude E,E-
dibenzalacetone (solubility of E,E-dibenzalacetone in 95%
ethanol at 78°C is 0.4 g/1 mL). Add two boiling stones. Label
from the Hirsch funnel directly into the Erlenmeyer flask
(the creased weighing paper is used solely to contain any spilled
material). Transfer any spilled material to the flask.
Reweigh the flask and determine the mass of the crude E,E-
dibenzalacetone. Retain a small sample of the crude E,E-
dibenzalacetone (about the size of a grain of uncooked rice) in a
small test tube for a melting point determination next
week.
Page 5 of 6
n. Discard the filter paper and weighing paper in the appropriate
solid waste container.
o. Discard the filtrate in the appropriate aqueous waste
container. Clean the filter flask, microspatula and Hirsch
funnel
with wash grade acetone.
STEP 3 Purification of the E,E-dibenzalacetone by
recrystallization (performed in the designated fumehood)
a. Transfer an appropriate volume of 95% ethanol to the 10 mL
Erlenmeyer flask containing your crude E,E-
dibenzalacetone (solubility of E,E-dibenzalacetone in 95%
ethanol at 78°C is 0.4 g/1 mL). Add two boiling stones. Label
your Erlenmeyer flask with your name (Sharpies® are available
at the Issue Room window).
b. Heat the Erlenmeyer flask on a hotplate stirrer in the Unit 5
recrystallization fumehood (do not leave unattended).
Once the entire sample has dissolved remove the flask from the
hotplate stirrer (exercise caution as the flask will be
very hot) and allow it to cool to room temperature, undisturbed
on the bench top, in the Unit 5 recrystallization
fumehood. To complete crystallization cool the flask in a
medium sized beaker containing a 3/4” layer of ice and water
(this may be performed at your lab bench).
STEP 4 Collection of the purified E,E-dibenzalacetone by
vacuum filtration (performed at your lab bench)
a. Using a metal clamp secure a 250 mL filter flask to the left
most vertical support bar. Fit the filter flask with a Hirsch
funnel equipped with a Hirsch funnel filter paper. Connect the
quick-fit adapters of the vacuum trap and filter flask. Your
apparatus should now resemble Figure 2.
b. Prepare to collect the crystals of purified E,E-
dibenzalacetone by wetting the filter paper on the funnel with a
little 95%
ethanol and applying full suction (using the house vacuum line).
Gently swirl the contents of the 10 mL Erlenmeyer flask
to suspend the crystalline material (use a microspatula to break
up any solid chunks) then pour this suspension into the
at the Issue Room window).
b. Heat the Erlenmeyer flask on a hotplate stirrer in the Unit 5
recrystallization fumehood (do not leave unattended).
Once the entire sample has dissolved remove the flask from the
hotplate stirrer (exercise caution as the flask will be
very hot) and allow it to cool to room temperature, undisturbed
on the bench top, in the Unit 5 recrystallization
fumehood. To complete crystallization cool the flask in a
medium sized beaker containing a 3/4” layer of ice and water
(this may be performed at your lab bench).
STEP 4 Collection of the purified E,E-dibenzalacetone by
vacuum filtration (performed at your lab bench)
a. Using a metal clamp secure a 250 mL filter flask to the left
most vertical support bar. Fit the filter flask with a Hirsch
funnel equipped with a Hirsch funnel filter paper. Connect the
quick-fit adapters of the vacuum trap and filter flask. Your
apparatus should now resemble Figure 2.
b. Prepare to collect the crystals of purified E,E-
dibenzalacetone by wetting the filter paper on the funnel with a
little 95%
ethanol and applying full suction (using the house vacuum line).
Gently swirl the contents of the 10 mL Erlenmeyer flask
to suspend the crystalline material (use a microspatula to break
up any solid chunks) then pour this suspension into the
Hirsch funnel. You may use small quantities of the chilled 95%
ethanol prepared earlier to aid in the transfer of your
crude product to the Hirsch funnel (2 mL at a time; but no more
than a total of 6 mL).
c. Dry the solid by continued suction for 5 minutes while
proceeding with other work.
d. Transfer the Hirsch funnel to a beaker, leaving the boiling
stones and filter-cake of crystals intact. Leave this assembly in
your locker until next week. This will provide an opportunity
for the crystals to dry thoroughly.
e. Discard the filtrate in the appropriate organic waste
container. Clean the filter flask and microspatula with wash
grade
acetone.
EXPERIMENTAL PROCEDURES NEXT LAB SESSION
STEP 5 Weighing the purified E,E-debenzalacetone (sample
vials are available at the front bench)
a. Place a pre-weighed sample vial on a piece of creased
weighing paper. Using a microspatula carefully transfer the
purified E,E-dibenzalacetone (though not the boiling stones)
from the Hirsch funnel directly into the sample vial (the
creased weighing paper is used solely to contain any spilled
material). Transfer any spilled material to the sample vial.
ethanol prepared earlier to aid in the transfer of your
crude product to the Hirsch funnel (2 mL at a time; but no more
than a total of 6 mL).
c. Dry the solid by continued suction for 5 minutes while
proceeding with other work.
d. Transfer the Hirsch funnel to a beaker, leaving the boiling
stones and filter-cake of crystals intact. Leave this assembly in
your locker until next week. This will provide an opportunity
for the crystals to dry thoroughly.
e. Discard the filtrate in the appropriate organic waste
container. Clean the filter flask and microspatula with wash
grade
acetone.
EXPERIMENTAL PROCEDURES NEXT LAB SESSION
STEP 5 Weighing the purified E,E-debenzalacetone (sample
vials are available at the front bench)
a. Place a pre-weighed sample vial on a piece of creased
weighing paper. Using a microspatula carefully transfer the
purified E,E-dibenzalacetone (though not the boiling stones)
from the Hirsch funnel directly into the sample vial (the
creased weighing paper is used solely to contain any spilled
material). Transfer any spilled material to the sample vial.
Reweigh the sample vial and determine the mass of purified
E,E-dibenzalacetone.
b. Discard the boiling stones, filter paper and weighing paper
into the appropriate solid waste container.
c. Clean the Hirsch funnel and microspatula with wash grade
acetone.
Page 6 of 6
STEP 6 Characterization of the crude and purified E,E-
dibenzalacetone (melting point capillary tubes are available at
the
front bench)
a. Retrieve two melting point capillary tubes. Using a Sharpie®
label the top of one with a single line. Label the top of the
other with two lines.
b. Place a few crystals of crude E,E-dibenzalacetone on the
ground-glass portion of a clean microscope slide (working over
a creased weighing paper will contain any spilled material).
Repeatedly crush the crystals into a smear using a clean
microspatula (TA will demonstrate).
E,E-dibenzalacetone.
b. Discard the boiling stones, filter paper and weighing paper
into the appropriate solid waste container.
c. Clean the Hirsch funnel and microspatula with wash grade
acetone.
Page 6 of 6
STEP 6 Characterization of the crude and purified E,E-
dibenzalacetone (melting point capillary tubes are available at
the
front bench)
a. Retrieve two melting point capillary tubes. Using a Sharpie®
label the top of one with a single line. Label the top of the
other with two lines.
b. Place a few crystals of crude E,E-dibenzalacetone on the
ground-glass portion of a clean microscope slide (working over
a creased weighing paper will contain any spilled material).
Repeatedly crush the crystals into a smear using a clean
microspatula (TA will demonstrate).
c. Clean the microspatula with wash grade acetone.
d. Place a few crystals of purified E,E-dibenzalacetone acid on
the ground-glass portion of a separate clean microscope
slide (working over a creased weighing paper will contain any
spilled material). Repeatedly crush the crystals into a
smear using a clean microspatula.
e. Fill the first capillary tube with crude E,E-dibenzalacetone in
the manner employed in Units 1 and 2.
f. Fill the second capillary tube with purified E,E-
dibenzalacetone in the manner employed in Units 1 and 2.
g. Discard the weighing papers in the appropriate solid waste
container.
h. Clean the microspatula and microscope slides with wash
grade acetone.
i. Using the method employed in Units 1 and 2 carryout
simultaneous melting point determinations of your crude and
purified samples of E,E-dibenzalacetone (using the same
MelTemp device). Don’t forget to record the voltage setting.
j. Discard the used melting point capillary tubes in the
appropriate waste glass container.
STEP 7 Submission of the purified E,E-dibenzalacetone
Affix a “E,E-DBA” label (available at the front bench) to your
sample vial. Submit vial as directed by instructor.
d. Place a few crystals of purified E,E-dibenzalacetone acid on
the ground-glass portion of a separate clean microscope
slide (working over a creased weighing paper will contain any
spilled material). Repeatedly crush the crystals into a
smear using a clean microspatula.
e. Fill the first capillary tube with crude E,E-dibenzalacetone in
the manner employed in Units 1 and 2.
f. Fill the second capillary tube with purified E,E-
dibenzalacetone in the manner employed in Units 1 and 2.
g. Discard the weighing papers in the appropriate solid waste
container.
h. Clean the microspatula and microscope slides with wash
grade acetone.
i. Using the method employed in Units 1 and 2 carryout
simultaneous melting point determinations of your crude and
purified samples of E,E-dibenzalacetone (using the same
MelTemp device). Don’t forget to record the voltage setting.
j. Discard the used melting point capillary tubes in the
appropriate waste glass container.
STEP 7 Submission of the purified E,E-dibenzalacetone
Affix a “E,E-DBA” label (available at the front bench) to your
sample vial. Submit vial as directed by instructor.
Page 1 of 4
Lecture
Notes
Chemistry 337
Unit 5 Synthesis of E,E-dibenzalacetone (E,E-DBA)
Introduction to Unit 5
The centerpiece of this unit is the synthesis of E,E-
dibenzalacetone (E,E-DBA) for which we will employ a base-
catalyzed aldol
condensation. The crude product will be purified by
recrystallization. The crude and purified products will be
characterized by
melting point determination.
H
O O
CH3CH3
O
Lecture
Notes
Chemistry 337
Unit 5 Synthesis of E,E-dibenzalacetone (E,E-DBA)
Introduction to Unit 5
The centerpiece of this unit is the synthesis of E,E-
dibenzalacetone (E,E-DBA) for which we will employ a base-
catalyzed aldol
condensation. The crude product will be purified by
recrystallization. The crude and purified products will be
characterized by
melting point determination.
H
O O
CH3CH3
O
NaOH, H2O, ethanol
Benzaldehyde Acetone E,E-dibenzalacetone
2
Purpose of Unit 5
To employ a based-catalyzed aldol condensation in the
synthesize of E,E-dibenzalacetone
To characterize the crude and purified samples of E,E-
dibenzalacetone by melting point determination
Overview of these lecture notes
These lecture notes provide guidelines for the preparation of
your Unit 5 formal report. Please note the aldol condensation
will
be covered in Unit 11. The chemistry of Unit 5 will be
discussed in the Unit 11 lecture notes. Recrystallization will be
discussed in the Unit 2 lecture notes.
Lecture notes
General comments about the formal lab report
One of the most difficult problems a student faces in this course
is estimating the appropriate length of the formal report. The
following guidelines are designed to help you with your report
preparation.
Benzaldehyde Acetone E,E-dibenzalacetone
2
Purpose of Unit 5
To employ a based-catalyzed aldol condensation in the
synthesize of E,E-dibenzalacetone
To characterize the crude and purified samples of E,E-
dibenzalacetone by melting point determination
Overview of these lecture notes
These lecture notes provide guidelines for the preparation of
your Unit 5 formal report. Please note the aldol condensation
will
be covered in Unit 11. The chemistry of Unit 5 will be
discussed in the Unit 11 lecture notes. Recrystallization will be
discussed in the Unit 2 lecture notes.
Lecture notes
General comments about the formal lab report
One of the most difficult problems a student faces in this course
is estimating the appropriate length of the formal report. The
following guidelines are designed to help you with your report
preparation.
As a general point of style, reports should be written
impersonally in the passive voice. While this style is somewhat
clumsy, it
is widely accepted in scientific writing. Although we are not
grading your reports for prose style and literary merit, we
suggest
that, to save your time and ours, you write in the simplest and
most direct English that you can command.
In order to provide adequate space for the grader’s comments
we ask that reports be set in double-spaced format and with a
2” right margin.
Page 2 of 4
Components of the formal lab report (portions of a sample
formal report are given on the next two pages)
Title, Name, Date (~3%)
Abstract (~5%)
State briefly the purpose of the experiment, the principal
results, the mode(s) of isolation, separation and purification (as
appropriate) and the major conclusions. You may refer to
schemes and tables found in the introduction, results and
discussion sections by number.
Introduction (~5%)
State clearly the synthetic goal of the experiment. Do not begin
your report with a lengthy description of background theory.
impersonally in the passive voice. While this style is somewhat
clumsy, it
is widely accepted in scientific writing. Although we are not
grading your reports for prose style and literary merit, we
suggest
that, to save your time and ours, you write in the simplest and
most direct English that you can command.
In order to provide adequate space for the grader’s comments
we ask that reports be set in double-spaced format and with a
2” right margin.
Page 2 of 4
Components of the formal lab report (portions of a sample
formal report are given on the next two pages)
Title, Name, Date (~3%)
Abstract (~5%)
State briefly the purpose of the experiment, the principal
results, the mode(s) of isolation, separation and purification (as
appropriate) and the major conclusions. You may refer to
schemes and tables found in the introduction, results and
discussion sections by number.
Introduction (~5%)
State clearly the synthetic goal of the experiment. Do not begin
your report with a lengthy description of background theory.
The time to demonstrate your knowledge of background theory
is in explaining the results you have obtained. One or two
paragraphs should be adequate. Include the appropriate
balanced chemical equation(s) (including structural drawings
for all
organic reactants and products, inorganic reagents above the
arrows, and solvents and conditions below the arrows) labeled
as Scheme 1. See Scheme 1 of the sample formal report.
Results (~35%)
Tabulation of experimental results is encouraged whenever it
leads to a more effective presentation. Tables must be in the
same format as Table 1 of the sample formal report. Graders
will not spend time rooting through pages of text searching for
experimental data. They will simply assign a grade of zero for
this portion of the report.
Discussion (~50%)
A separate paragraph should be included for each one of the
following items:
-a written account of how the product was prepared (i.e. a
description of the chemistry involved) along with appropriate
references to any balanced reaction equations given elsewhere
(e.g. in the introduction)
-a written account of how the crude product was isolated
(include chemistry if appropriate)
-a written account of how the crude product was identified,
wherein you cite and interpret relevant experimental data
making
reference to appropriate literature data
is in explaining the results you have obtained. One or two
paragraphs should be adequate. Include the appropriate
balanced chemical equation(s) (including structural drawings
for all
organic reactants and products, inorganic reagents above the
arrows, and solvents and conditions below the arrows) labeled
as Scheme 1. See Scheme 1 of the sample formal report.
Results (~35%)
Tabulation of experimental results is encouraged whenever it
leads to a more effective presentation. Tables must be in the
same format as Table 1 of the sample formal report. Graders
will not spend time rooting through pages of text searching for
experimental data. They will simply assign a grade of zero for
this portion of the report.
Discussion (~50%)
A separate paragraph should be included for each one of the
following items:
-a written account of how the product was prepared (i.e. a
description of the chemistry involved) along with appropriate
references to any balanced reaction equations given elsewhere
(e.g. in the introduction)
-a written account of how the crude product was isolated
(include chemistry if appropriate)
-a written account of how the crude product was identified,
wherein you cite and interpret relevant experimental data
making
reference to appropriate literature data
-a written account of how the crude product was purified and an
evaluation of the efficiency of the purification, wherein you cite
and interpret relevant experimental data making reference to
appropriate literature data
-a written account of how the purified product was identified,
wherein you cite and interpret relevant experimental data
making
reference to appropriate literature data
-a discussion of yields
Please remember, we are looking for an account of the results
you obtained and the conclusions that you drew from them.
Experimental Procedure (~2%)
Do not copy out the complete experimental procedure from the
manual. “The preparation was carried out according to the
prescribed method” will be sufficient in many instances.
Page 3 of 4
Sample formal lab report (except for the discussion) for you to
use
Preparation Of E-α-Phenylcinnamic Acid And Z-α-
Phenylcinnamic Acid
evaluation of the efficiency of the purification, wherein you cite
and interpret relevant experimental data making reference to
appropriate literature data
-a written account of how the purified product was identified,
wherein you cite and interpret relevant experimental data
making
reference to appropriate literature data
-a discussion of yields
Please remember, we are looking for an account of the results
you obtained and the conclusions that you drew from them.
Experimental Procedure (~2%)
Do not copy out the complete experimental procedure from the
manual. “The preparation was carried out according to the
prescribed method” will be sufficient in many instances.
Page 3 of 4
Sample formal lab report (except for the discussion) for you to
use
Preparation Of E-α-Phenylcinnamic Acid And Z-α-
Phenylcinnamic Acid
Your Name
Submission Date
Title (11 pt, bold)
Name (11 pt)
Date (11 pt,
italics)
Abstract
The preparation of Z-α-phenylcinnamic acid (1) and E-α-
phenylcinnamic acid (2) (Scheme 1), from
benzaldehyde and phenylacetic acid in the presence of
triethylamine and acetic anhydride, is
described. Both acids were purified by recrystallization; Z-α-
phenylcinnamic acid was
recrystallized from methanol/water and E-α-phenylcinnamic
acid was recrystallized from diethyl
ether/petroleum ether. Z-α-Phenylcinnamic acid was obtained
in 13.0% yield. E-α-
Phenylcinnamic acid was obtained in 26.7% yield. The acids
were characterized by melting point,
infrared spectroscopy and proton NMR spectroscopy.
Introduction
The purpose of this experiment was to employ the Perkin
Reaction in the preparation of Z-α-
phenylcinnamic acid (1) and E-α-phenylcinnamic acid (2). As
outlined in Scheme 1 this involved
allowing benzaldehyde to react with phenylacetic acid at reflux
in the presence of triethylamine and
acetic anhydride.
Submission Date
Title (11 pt, bold)
Name (11 pt)
Date (11 pt,
italics)
Abstract
The preparation of Z-α-phenylcinnamic acid (1) and E-α-
phenylcinnamic acid (2) (Scheme 1), from
benzaldehyde and phenylacetic acid in the presence of
triethylamine and acetic anhydride, is
described. Both acids were purified by recrystallization; Z-α-
phenylcinnamic acid was
recrystallized from methanol/water and E-α-phenylcinnamic
acid was recrystallized from diethyl
ether/petroleum ether. Z-α-Phenylcinnamic acid was obtained
in 13.0% yield. E-α-
Phenylcinnamic acid was obtained in 26.7% yield. The acids
were characterized by melting point,
infrared spectroscopy and proton NMR spectroscopy.
Introduction
The purpose of this experiment was to employ the Perkin
Reaction in the preparation of Z-α-
phenylcinnamic acid (1) and E-α-phenylcinnamic acid (2). As
outlined in Scheme 1 this involved
allowing benzaldehyde to react with phenylacetic acid at reflux
in the presence of triethylamine and
acetic anhydride.
Scheme 1
H
CO2H H CO2HCHO CH2COH
O
1. triethylamine,
acetic anhydride, Δ
2. H+, H2O
21
Abstract title (10
pt, bold)
Abstract (10 pt,
double spaced)
-should state
briefly the purpose
of the experiment,
the principal
results and major
conclusions.
Reference to
structural formulas
or tables in the
text, by number,
may be made in
the abstract.
Introduction title
(10 pt, bold)
H
CO2H H CO2HCHO CH2COH
O
1. triethylamine,
acetic anhydride, Δ
2. H+, H2O
21
Abstract title (10
pt, bold)
Abstract (10 pt,
double spaced)
-should state
briefly the purpose
of the experiment,
the principal
results and major
conclusions.
Reference to
structural formulas
or tables in the
text, by number,
may be made in
the abstract.
Introduction title
(10 pt, bold)
Introduction (10
pt, double spaced)
-should clearly
state the purpose
and objectives of
the experiment. In
general, the
introduction
should be no more
than one or two
paragraphs.
Page 4 of 4
Results
The results of the synthesis of Z-α-phenylcinnamic acid and E-
α-phenylcinnamic acid are
summarized in Table 1.
Table 1. Synthesis of Z-α-Phenylcinnamic Acid And E-α-
Phenylcinnamic Acid
* white crystalline material
pt, double spaced)
-should clearly
state the purpose
and objectives of
the experiment. In
general, the
introduction
should be no more
than one or two
paragraphs.
Page 4 of 4
Results
The results of the synthesis of Z-α-phenylcinnamic acid and E-
α-phenylcinnamic acid are
summarized in Table 1.
Table 1. Synthesis of Z-α-Phenylcinnamic Acid And E-α-
Phenylcinnamic Acid
* white crystalline material
Compound
molar
mass
(g/mol)
volume/mass
moles
yield mp
(°C)
phenylacetic acid
(limiting reagent)
136.15 5.00 g
0.0368 moles
N/A 77°C
acetic anhydride
(density 1.08 g/mL)
102.09 4.00 mL
4.32 g
0.0423 moles
N/A N/A
benzaldehyde
(density 1.046 g/mL)
106.12 6.00mL
6.28 g
molar
mass
(g/mol)
volume/mass
moles
yield mp
(°C)
phenylacetic acid
(limiting reagent)
136.15 5.00 g
0.0368 moles
N/A 77°C
acetic anhydride
(density 1.08 g/mL)
102.09 4.00 mL
4.32 g
0.0423 moles
N/A N/A
benzaldehyde
(density 1.046 g/mL)
106.12 6.00mL
6.28 g
0.0592 moles
N/A N/A
triethylamine
(density 0.729 g/mL)
101.19 4.00 mL
2.92 g
0.0289 moles
N/A N/A
α-phenyl-cinnamic
acids
224.26 8.23 g
0.0368 moles
(theoretical yield)
174 (E)
138 – 139 (Z)
(literature values)
Z-α-phenyl-cinnamic
acid
224.26 2.38* g; 28.9% (crude)
1.07* g; 13.0% (purified)
125.0 – 129.1
(crude)
N/A N/A
triethylamine
(density 0.729 g/mL)
101.19 4.00 mL
2.92 g
0.0289 moles
N/A N/A
α-phenyl-cinnamic
acids
224.26 8.23 g
0.0368 moles
(theoretical yield)
174 (E)
138 – 139 (Z)
(literature values)
Z-α-phenyl-cinnamic
acid
224.26 2.38* g; 28.9% (crude)
1.07* g; 13.0% (purified)
125.0 – 129.1
(crude)
134.1 – 135.9
(purified)
E-α-phenyl-cinnamic
acid
224.26 3.84* g; 46.7% (crude)
2.20* g; 26.7% (purified)
167.0 – 171.0
(crude)
173.0 – 173.5
(purified)
Results title (10
pt, bold)
Results (10 pt,
double spaced)
-tabulation of
experimental
results is
encouraged
whenever it
leads to a more
effective
presentation.
(purified)
E-α-phenyl-cinnamic
acid
224.26 3.84* g; 46.7% (crude)
2.20* g; 26.7% (purified)
167.0 – 171.0
(crude)
173.0 – 173.5
(purified)
Results title (10
pt, bold)
Results (10 pt,
double spaced)
-tabulation of
experimental
results is
encouraged
whenever it
leads to a more
effective
presentation.
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Great history of astronomy from long ago till today
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History of astronomy from old times to the present times
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