ethyl 4-amino-3-oxobutanoate;hydrochloride

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2.5 g of ethyl (ethylthio)iminoacetate tetrafluoroborate, 110 ml of acetic acid, 1.8 g of ethyl 4-aminoacetoacetate hydrochloride and 1.64 g of sodium acetate is heated for 3 hours at a temperature close to 95° C. The reaction mixture is filtered and the insoluble matter is rinsed with 3×5 ml of acetic acid. The filtrate is evaporated in a rotary evaporator and the evaporation residue is supplemented with 75 ml of dichloromethane. The organic solution is dried over sodium sulphate, filtered and evaporated in a rotary evaporator. The evaporation residue (1.86 g) is purified by chromatography on a silica column, eluting with ethyl acetate. 1.5 g of ethyl 4-(ethoxycarbonylmethyl)imidazole-2-carboxylate are obtained in the form of a red-yellow solid melting at 88° C. is heated for 3 hours at a temperature close to 95° C The reaction mixture is filtered the insoluble matter is rinsed with 3×5 ml of acetic acid The filtrate is evaporated in a rotary evaporator The organic solution is dried over sodium sulphate filtered evaporated in a rotary evaporator The evaporation residue (1.86 g) is purified by chromatography on a silica column eluting with ethyl acetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 2.5 g of ethyl (ethylthio)iminoacetate tetrafluoroborate, 110 ml of acetic acid, 1.8 g of ethyl 4-aminoacetoacetate hydrochloride and 1.64 g of sodium acetate is heated for 3 hours at a temperature close to 95° C. The reaction mixture is filtered and the insoluble matter is rinsed with 3×5 ml of acetic acid. The filtrate is evaporated in a rotary evaporator and the evaporation residue is supplemented with 75 ml of dichloromethane. The organic solution is dried over sodium sulphate, filtered and evaporated in a rotary evaporator. The evaporation residue (1.86 g) is purified by chromatography on a silica column, eluting with ethyl acetate. 1.5 g of ethyl 4-(ethoxycarbonylmethyl)imidazole-2-carboxylate are obtained in the form of a red-yellow solid melting at 88° C. is heated for 3 hours at a temperature close to 95° C The reaction mixture is filtered the insoluble matter is rinsed with 3×5 ml of acetic acid The filtrate is evaporated in a rotary evaporator The organic solution is dried over sodium sulphate filtered evaporated in a rotary evaporator The evaporation residue (1.86 g) is purified by chromatography on a silica column eluting with ethyl acetate