Practical Experiment 6: To synthesize and characterized 2,3 diphenyl quninoxaline from orthophenelene diamnine (opd)

To synthesize and characterized 2,3 diphenyl quninoxaline from orthophenelene diamnine (opd)

1. Experiment 6 To synthesize and characterized 2,3- diphenylquinoxaline from orthophenelene diamine (OPD). Presented By…. Prof. Sonali R. Pawar Medicinal Chemistry I B. Pharmacy IV semester

2. Title : Synthesis of 2,3-Diphenyl quinoxaline from O- phenylene diamine (OPD). Aim : To synthesize and characterized 2,3-Diphenyl quinoxaline from O- phenylene diamine (OPD). Chemicals   Filter Paper   Red & blue litmus paper   1. O- phenylene diamine 1.1 gm Benzil 2.1 gm Rectified Spirit 8 ml

3. Principle: It is a pinacol rearrangement reaction: When O- phenylene diamine react with benzyl will give 2,3-Diphenyl quinoxaline , they can form by condensing O- diamine with 1,2-ketone the parent substance of the group quinoxaline glycoxal is condensed with 1,2-diaminobenzene quinoxaline and its analouges may also form by reduction of amino acid. Substituted 1,2-diphenyl quinoxaline form by condensation by benzyl and O- phenylene diamine.

4. Procedure: 1) To a warm solution of 2.1 gm (0.01 mol ) of benzyl in 8 ml of rectified spirit. 2) Add a solution of 1.1 gm (0.01 mol ) of O- phenylene diamine in 8 ml of rectified spirit. 3) Warm in a water bath for 30 min. 4) Add water until a slight cloud in perrist . 5) Allow to cool, filter and recrystallizes from aqueous ethanol to give 1.43 gm (51%) of 2,3-Diphenyl quinoxaline. (Melting poing : 125-126 °C) Used as anti-viral, anti-bacterial, anti-inflammatory, anti-protozoal, anti-cancer (colon cancer therapies), antidepressant, anti-HIV agent and as kinase inhibitor etc.

5. CALCULATIONS :- Molecular weight of 2,3-diphenyl quinoxaline = 282.3gm/M Molecular weight of OPD= 108.14gm/M Weight taken of OPD = 1.1gm/M Practical yield = 2.83gm X(theoretical yield )=molecular weight 2,3-diphenyl quinoxaline x weight of OPD taken molecular weight of OPD =282.3g/M x 1.1g/108.14g/M = 2.86gm Percentage yield = practical yield /theoretical yieldx100% Percentage yield = 2.83/2.86x100 % Percentage yield = 98.95%

6. Calculation: TLC: Structure:    Formula:   C 10 H 14 N 2 Theorotical Yield:   2.86gm Practical Yield:   2.83gm % Yield:   98.95% Melting/Boiling Point:   125 c – 126 c R f Value:   0.53

7. SRP:Cholinergic Neurotransmitter 7