Dimethylcarbamoyl Chloride → 1-Boc-4-dimethylcarbamoylpiperazine

Participants

Reaction Steps

To a solution of 1.92 g 1-(1,1-dimethylethyloxycarbonyl)piperazine in 11 mL of dichloromethane and 1.5 mL of triethylamine at room temperature w,as added dropwise 1 mL of dimethylcarbamylchloride. After 16 hours 5% aqueous sodium hydrogencarbonate and dichloromethane were added, the organic layer separated, dried over magnesium sulfate and concentrated. Column chromatography on silica gel (dichloromethane/methanol=95/5 v/v) yielded 1.34 g 1-(1,1-dimethylethyloxycarbonyl)-4-(dimethylaminocarbonyl)piperazine. This compound was dissolved in a 3N hydrogen chloride solution in methanol at 0° C. After 15 min the reaction mixture was allowed to warm to room temperature and After stirring for 3 days at room temperature the reaction mixture was concentrated to give 1.06 g of 1-(dimethylaminocarbonyl)piperazine hydrochloride. rf=0.29, SiO2: dichloromethane/methanol=4/1 v/v.

Provenance & Evidence