3-Chloropropanesulphonyl chloride → 4-tert-Butoxycarbonyl-1-[(3-chloro-1-propyl)sulfonyl]piperazine

Participants

Reaction Steps

To 1-BOC-piperazine (6.00 g) in dry dichloromethane (60 ml) and triethylamine (5.85 ml) at 0° C. was added 3-chloropropanesulfonyl chloride (4.5 ml). The reaction mixture was stirred for 2 hours, diluted with dichloromethane, washed with brine, dried (MgSO4), filtered and volatiles removed in vacuo. Purification on silica gave 4-(3-chloro-propane-1-sulfonyl)-piperazine-1-carboxylic acid tert-butyl ester (9.85 g). This was reacted with dimethylamine hydrochloride in acetonitrile and potassium carbonate to give 4-(3-dimethylamino-propane-1-sulfonyl)-piperazine 1-carboxylic acid tert-butyl ester. BOC-group was removed using HCl in ether under standard procedures to give the title compound.

Provenance & Evidence