Chlorosulfonyl isocyanate → 2-Oxindole-1-carboxamide

Participants

Reaction Steps

Chlorosulfonyl isocyanate (1.20 g, 8.4 mmoles) was added to a mixture of 2-oxindole (0.94 g, 7.1 mmole) in ether (30 ml) and the reaction stirred at room temperature for 20 hours. The ether was removed under vacuum and the residue treated with water (10 ml) and 1N HCl (10 ml). Ethyl acetate (125 ml) was added and the mixture stirred for one hour. The ethyl acetate phase was separated, washed with 1N HCl (1×50 ml), brine (2×100 ml) and dried (MgSO4). Concentration afforded 0.97 g (77%) of crude product. Recrystallization from ethanol gave 0.18 g; m.p. 178°-180° C.

Provenance & Evidence