4-Nitrobenzenesulfonyl chloride → N-((4-Nitrophenyl)sulfonyl)-1-(tert-butyloxycarbonyl)piperazine

Participants

Reaction Steps

Diisopropylethylamine (7.8 ml, 45 mmol) was added in one portion to a stirred solution of piperazine-1-carboxylic acid tert-butyl ester (7.6 g, 41 mmol) in DCM (100 ml) at room temperature. To this mixture was added 4-nitrophenyl sulfonyl chloride (10.0 g, 45 mmol) in one portion and the mixture was stirred at room temperature under a nitrogen atmosphere for 1 hour. After this time the mixture was diluted with DCM (50 ml) and washed with water (100 ml), saturated NaHCO3 (100 ml) and HCl (100 ml, 2M). The organic layer was separated, dried (MgSO4), filtered and concentrated under vacuum to give the title compound (14.9 g, 89% yield) as a white solid. δH (500 MHz, DMSO) 8.45 (2H, d), 7.97 (2H, d), 3.34 (4H, obscured), 2.96-2.92 (4H, m), 1.33 (9H, s). Tr=1.91 min m/z (ES+) ([(M−100)+H]+) 272.

Provenance & Evidence