benzyl N-(4-bromobutyl)carbamate

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

Procedure: An ethanol (130.2 ml) solution of sodium ethoxide (5.83 g) was added with diethyl malonate (13 ml) and stirred at room temperature for 5 minutes. This solution was added with an ethanol (55.8 ml) solution of the 1-benzyloxycarbonylamino-4-bromobutane (4.9 g) obtained in the above step (b), and stirred at 40° C. for 20 hours. The reaction system was concentrated under reduced pressure without any treatment, and the residue was added with saturated aqueous ammonium chloride, and then the organic substances were extracted with ethyl acetate. The organic layer was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (1.2 kg, hexane:ethyl acetate=2:1) to obtain diethyl 2-(4-benzyloxycarbonylaminobutyl)malonate (5.2 g, 83%). obtained in the above step (b) stirred at 40° C. for 20 hours The reaction system was concentrated under reduced pressure without any treatment the residue was added with saturated aqueous ammonium chloride the organic substances were extracted with ethyl acetate The organic layer was concentrated under reduced pressure the residue was purified by silica gel column chromatography (1.2 kg, hexane:ethyl acetate=2:1)

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

Procedure: An ethanol (130.2 ml) solution of sodium ethoxide (5.83 g) was added with diethyl malonate (13 ml) and stirred at room temperature for 5 minutes. This solution was added with an ethanol (55.8 ml) solution of the 1-benzyloxycarbonylamino-4-bromobutane (4.9 g) obtained in the above step (b), and stirred at 40° C. for 20 hours. The reaction system was concentrated under reduced pressure without any treatment, and the residue was added with saturated aqueous ammonium chloride, and then the organic substances were extracted with ethyl acetate. The organic layer was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (1.2 kg, hexane:ethyl acetate=2:1) to obtain diethyl 2-(4-benzyloxycarbonylaminobutyl)malonate (5.2 g, 83%). obtained in the above step (b) stirred at 40° C. for 20 hours The reaction system was concentrated under reduced pressure without any treatment the residue was added with saturated aqueous ammonium chloride the organic substances were extracted with ethyl acetate The organic layer was concentrated under reduced pressure the residue was purified by silica gel column chromatography (1.2 kg, hexane:ethyl acetate=2:1)