tert-butyl 2-isocyanato-2-methylpropanoate

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Into a 100-mL 3-necked round-bottom flask was placed a solution of tert-butyl 2-amino-2-methylpropanoate (1.2 g, 7.54 mmol, 1.00 equiv) in dichloromethane (20 mL). This was followed by the addition of ditrichloromethyl carbonate (750 mg, 2.53 mmol, 0.34 equiv), in portions at 0° C. After 30 min, triethylamine (2.3 g, 22.73 mmol, 3.02 equiv) was added dropwise with stirring. The resulting solution was stirred for 5 h at room temperature and then concentrated under vacuum. The residue was diluted with 20 mL of ethyl ether. The solids were filtered out. The filtrate was concentrated under vacuum. Purification afforded 1.4 g (crude) of tert-butyl 2-isocyanato-2-methylpropanoate (110.2) as a yellow oil. Into a 100-mL 3-necked round-bottom flask was placed The resulting solution was stirred for 5 h at room temperature concentrated under vacuum The residue was diluted with 20 mL of ethyl ether The solids were filtered out The filtrate was concentrated under vacuum Purification

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Into a 100-mL 3-necked round-bottom flask was placed a solution of tert-butyl 2-amino-2-methylpropanoate (1.2 g, 7.54 mmol, 1.00 equiv) in dichloromethane (20 mL). This was followed by the addition of ditrichloromethyl carbonate (750 mg, 2.53 mmol, 0.34 equiv), in portions at 0° C. After 30 min, triethylamine (2.3 g, 22.73 mmol, 3.02 equiv) was added dropwise with stirring. The resulting solution was stirred for 5 h at room temperature and then concentrated under vacuum. The residue was diluted with 20 mL of ethyl ether. The solids were filtered out. The filtrate was concentrated under vacuum. Purification afforded 1.4 g (crude) of tert-butyl 2-isocyanato-2-methylpropanoate (110.2) as a yellow oil. Into a 100-mL 3-necked round-bottom flask was placed The resulting solution was stirred for 5 h at room temperature concentrated under vacuum The residue was diluted with 20 mL of ethyl ether The solids were filtered out The filtrate was concentrated under vacuum Purification