Alkynes

Alkynes presentation

1. Alkynes

2. Group Members Novella I.C (20) Nurul Izzatil A. (21) R. Dandy Y. (22) Raka S.W.S (23) Reyan P.B . (24) Rizqi Cahyo .Y (25) Rosita Devi (26) Sabrina Amelia J. (27) Zaynita A . A (28) X-1

3. Alkynes Alkynes are aliphatic hydrocarbons (straight chain ),   unsaturated hydrocarbon  with a triple bond  between two  carbon  atoms. Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C2H2 , known formally as  ethyne  using  IUPAC  nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic but tend to be more reactive. It is widely thought to be the greatest of all the functional groups.

4. Common Formula of Alkynes C n H 2n -2 n : Number of C

5. Function of Common Formula of Alkynes Determine the molecular formula  alkynes   compounds. The molecular structure of these compounds can be described by the molecular formula. Example : Number of Carbons: 3 Index  Numbers of Hydrogen : 2(3)-2 = 6-2 = 4 Molecular Formula: C 3 H 4

6. Number of Carbons: 5 Index Numbers of Hydrogens : 2(5 )-2 = 10-2 = 8 Molecular Formula: C 5 H 8 Number of Carbons: 7 Index Numbers of Hydrogen: 2(7)-2 = 14-2 = 12 Molecular Formula: C 7 H 12 Number of Carbons: 9 Index Numbers of Hydrogen: 2(9)-2 = 18-2 = 16 Molecular Formula: C 9 H 16 http:// chemistry.about.com /od/ lecturenoteslabs / tp /Simple-Alkyne- Chains.htm

7. Nomenclature of Alkynes

8. Straight Chain Check the type of bond, if it has a triplicate bond , meaning the compound is an  alkyne compound. Count the number of its C  atom. Write the prefix based on the number of its C atom and ending with the suffix- una . If the number of C atoms alkyne compounds of more than 3, give the number of each atom  in such a way that the smallest number is located on the C atom attached to a triple bond. Then, naming compounds is initiated by the first C atom numbers are bound to  triplicate bonds, followed by a dash (-) and the name of the main chain . http:// smartchemistry.wordpress.com /2012/02/14/ tata-nama-senyawa-alkuna /

9. Example 2 - Pentyne Butyne

10. Branched Chain Check the type of bond, if it has a triplicate bond, meaning the compound is an  alkyne compound. Determine the main chain and branch chain. The main chain  is determined from the longest chain of C atoms containing a triplicate bond. Give  the number of each atom in such a way that the smallest number is located on the  C atom  attached to a triplicate bond. The main  chain are named by the rules  straight chain alkyne compound  naming. Branched chain named after the number of C atoms and the structure of the alkyl group. Order in a compound name with a sequence of writing the name of the compound alkanes  and alkenes. http:// smartchemistry.wordpress.com /2012/02/14/ tata-nama-senyawa-alkuna /

11. Example 3- methyle -1- butyne (true) 2- methyle -3- butyne (false) 2,2- dimethyle -3- heptyne

12. Although the determination is wrong because the one of the main chain has the longest chain, but doesn't through the triplicate.

13. http:// www.chem -is- try.org / materi_kimia / kimia_organik_dasar / hidro-karbon / alkuna / Determining of the main chain is true (Name: 3,5- dimethyle -3- prophyle -1- hexyne

14. Triplicate bond More than One Check the type of bond, if it has a triple bond, meaning the compound is an alkyne compound. Count the number of its C atom. Count the number of triplicate bond. If the number of all triplicate bonds = 2, compound names end with the suffix- diuna . If the number of all triplicate bonds = 3, compound names end with the suffix- triuna . Give the number of each atom in such a way that the smallest number is located in two or three C atoms bound to the first triplicate bond. Then, naming compounds C atom numbers preceded by the first and second / third that bound to the triplicate bond, followed by a dash (-) and the name of the main chain. If there is a branched-chain, branched chain names similar to the naming of alkyne compounds.

15. 1,3- Pentadiyne

16. Physical and Chemical Properties of Alkyne

17. Physical Properties of Alkyne Alkyne is non-polar, have intermolecular forces are weak and  have a  molecular  masssimilar to alkanes and alkenes . The higher interest alkyne, the greater the boiling point . At room temperature, the first three tribes  are gaseous, the next  rates   are liquid, while  the greater rates are in  solid shape

18. Some physical properties of the alkyne Nama alkuna Molecular formula Mr Melting point (oC) Boiling point (0 C) Density (g/Cm3 ) On phase 250 C Etyne C2H2 26 -81 -85 - Gas Propyne C3H4 40 -103 -23 - Gas But-1-yne C4H6 54 -126 8 - Gas Pen-1-yne C5H8 68 -90 40 0,690 Cair Hex-1-yne C6H10 82 -132 71 0,716 Cair Hept-1-yne C7H12 96 -81 100 0,733 Cair Okt-1-yne C8H14 110 -79 126 0,740 Cair Non-1-yne C9H16 124 -50 151 0,766 Cair Dec-1-yne C10H18 138 -44 174 0,765 Cair

19. Chemical Properties of Alkyne With the same amount of C, the alkyne is more reactive than  alkanes The existence of a triple bond which is owned alkyne allow the addition reactions , polymerization , substitution and combustion

20. A. Addition reaction of  alkynes In contrast to alkenes, alkynes have triple bonds so  the adition  reaction can take place in two   stages Example Alkyne adition with the halogen

21. Alkyne adition to the halide acid Markovnikov    law applicable, H  atoms of hydrogen halides into atoms C double bind more H atoms.

22. B.  Polymerization reaction of alkynes In the etyne addition polymerization reaction (C2H2 ), two  molecules etyne  combine to form  one molecule   vinyl etyne  (C4H4 )

23. C. Substitution reaction of alkynes Substitution  on the alkyne reaction involves the release of H atoms bound to the  C C   bond at  the end of the chain of   alkyne 2CH CH + 2Na      2CH C - Na + H 2   CH C-CH 3 + NaI Et y n e    natrium asetilid e             prop y n e

24. D. Combustion reaction of alkynes Combustion  alkyne with a limited amount of O2, CO or C will result in 2C 2 H 2 (g)  +  5O 2 (g)               4CO 2 (g)  +  2H 2 O(g)

25. A lkyne   Isomers

26. Alkyne Isomers Type of the   alkyne isomers i structure isomers,  namely  framework/chain isomers and position isomers. Isomers of alkyne is started from alkyne   butyne.

27. Examples of C 5 H 8   isomers : Chain isomers Pen-1-yne 3-methyl but-1-yne Position isomers Pen-1-yne Pen-2-yne

28. Alkyne also get isomers with cycloalkene that called functional group isomers C 4 H 6 Functional group isomers CH CH 2 CH CH CH 2 CH CH CH 3 Cyclobutene 3-methyl cyclopropene

29. Thank You