methyl 3-isocyanatopropanoate

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

Procedure: To a solution containing 603.6 g of β-alanine-methylester sulfate and 1.5 liter of methyl alcohol, 1,256 ml of triethylamine was added at a freezing point and thereto, 235 ml of carbon disulfide was added dropwise at 10° C. or less. After the dropwise addition, the solution was stirred at 10° C. or less for 1 hour and then 288 ml of ethylchloroformate was added dropwise and in this state, the solution was stirred for 2 hours. After the reaction, the reaction solution was subjected to liquid separation with ethyl acetate and water. The extracted ethyl acetate layer was dried over magnesium sulfate and filtered and then the ethyl acetate was removed by distillation under reduced pressure to 389.1 g (yield: 89.3%) of the objective compound as an oily product. was added at a freezing point After the dropwise addition the solution was stirred for 2 hours After the reaction the reaction solution was subjected to liquid separation with ethyl acetate and water The extracted ethyl acetate layer was dried over magnesium sulfate filtered

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

Procedure: To a solution containing 603.6 g of β-alanine-methylester sulfate and 1.5 liter of methyl alcohol, 1,256 ml of triethylamine was added at a freezing point and thereto, 235 ml of carbon disulfide was added dropwise at 10° C. or less. After the dropwise addition, the solution was stirred at 10° C. or less for 1 hour and then 288 ml of ethylchloroformate was added dropwise and in this state, the solution was stirred for 2 hours. After the reaction, the reaction solution was subjected to liquid separation with ethyl acetate and water. The extracted ethyl acetate layer was dried over magnesium sulfate and filtered and then the ethyl acetate was removed by distillation under reduced pressure to 389.1 g (yield: 89.3%) of the objective compound as an oily product. was added at a freezing point After the dropwise addition the solution was stirred for 2 hours After the reaction the reaction solution was subjected to liquid separation with ethyl acetate and water The extracted ethyl acetate layer was dried over magnesium sulfate filtered

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

Procedure: In 600 ml of dry toluene was dissolved 26.4 g of monomethyl succinate, followed by the addition of 55 g of diphenylphosphorylazide and 22 g of triethylamine. The mixture was allowed to stand at room temperature with stirring for 3 hours, after which it was washed with water and dried. The solvent was concentrated to about one-third of its original volume and, finally, the mixture was refluxed for 2 hours. After the solvent was completely evaporated off, the residue was distilled under reduced pressure. By the above procedure there was obtained 13.6 g of the above-indicated compound. b.p.8 : 64°-66° C. to stand at room temperature after which it was washed with water dried The solvent was concentrated to about one-third of its original volume finally, the mixture was refluxed for 2 hours After the solvent was completely evaporated off the residue was distilled under reduced pressure

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

Procedure: To a solution containing 603.6 g of β-alanine-methylester sulfate and 1.5 liter of methyl alcohol, 1,256 ml of triethylamine was added at a freezing point and thereto, 235 ml of carbon disulfide was added dropwise at 10° C. or less. After the dropwise addition, the solution was stirred at 10° C. or less for 1 hour and then 288 ml of ethylchloroformate was added dropwise and in this state, the solution was stirred for 2 hours. After the reaction, the reaction solution was subjected to liquid separation with ethyl acetate and water. The extracted ethyl acetate layer was dried over magnesium sulfate and filtered and then the ethyl acetate was removed by distillation under reduced pressure to 389.1 g (yield: 89.3%) of the objective compound as an oily product. was added at a freezing point After the dropwise addition the solution was stirred for 2 hours After the reaction the reaction solution was subjected to liquid separation with ethyl acetate and water The extracted ethyl acetate layer was dried over magnesium sulfate filtered