Effect of enantiopure Schiff base of catalytic asymmetric diethyzinc addition to aldehydes

Here in this thesis, first of all, (S)-3-Amino-2-(1-hydroxy-2-methylpropyl)quinazolin-4(3H)-one70was synthesized starting from optically pure L-valin in four steps. Afterwards, purity of the (S)-3-Amino-2-(1-hydroxy-2-methylpropyl)quinazolin-4(3H)-one70waschecked using HPLC, 1H and 13C NMR. Subsequently, (S)-3-Amino-2-(1-hydroxy-2-methylpropyl)quinazolin-4(3H)-one70was converted into its Schiff base derivative using 2-methoxybenzaldehyde in the presence of ethanol. Then, characterisation of the (S)-2-(1-hydroxy-2-methylpropyl)-3-((2-methoxybenzylidene)amino)quinazolin-4(3H)-one68 was carried out by 1H and 13C NMR, IR, Elemental Analysis, Melting Points, Polarimeteras well as by HPLC using a chiral column and used further.In the last step, optically pure (S)-2-(1-hydroxy-2-methylpropyl)-3-((2-methoxybenzylidene)amino)quinazolin-4(3H)-one 68was used in catalytic enantioselective diethylzinc addition to aldehydes gave otically enriched secondary alcohols. The best enantiomeric excess 85% and 67% product yield was obtained from benzaldehyde derived 1-phenyl-1-propanol.