52nd International Chemistry Olympiad, Istanbul, TURKEY
Preparatory problems: PRACTICAL
Problem P6. 2,3-Dihydro-5,6-diphenylpyrazine An imine is a functional group or chemical compound containing a carbon–nitrogen double bond. Some imine compounds can sometimes be referred to as Schiff bases. Imines may find utility in a wide range of contexts, including the development antimicrobial, antiviral and anticancer agents. Imines are also common intermediates in enzymatic reactions and are used as common ligands in coordination chemistry. They are also used in nanotechnology for water treatment, encapsulation and functionalized magnetic nanoparticle production. In this experiment you are asked to synthesize 2,3-dihydro-5,6-diphenylpyrazine (DPP) through an imine formation reaction, starting from benzil and ethylenediamine.
Chemicals Substance C14H10O2 H2NCH2CH2NH2
C2H5OH
Name Benzil
State Solid
GHS Hazard Statement H315, H319, P302 + P352, P305 + P351 + P338 Ethylenediamine Liquid H226, H302 + H332, H311, H314, H317, H334, H412, P210, P273, P280, P301 + P330 + P331, P302 + P352, P304 + P340, P305 + P351 + P338, P308 + P310 Ethanol Liquid H225, H319, P210, P305 + P351 + P338
Glassware and equipment
1 Round-bottom flask, 250 mL 1 Stirring bar 1 Pipette, 10 mL 1 Reflux condenser 1 Beaker, 100 mL 1 Crystallization dish, 500 mL 204
