Potassium Cyanide → 1,3-benzothiazole-2-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A suspension of potassium cyanide (1.50 g, 23.0 mmol) in dimethylsulfoxide (DMSO, 100 mL) was prepared in a 1-L 3-necked flask fitted with a reflux condenser, a heating mantle and an internal temperature probe. The 2-chlorobenzothiazole (2.6 g, 2.0 mL, 15.3 mmol) was added to the reaction flask via pipet and the reaction was heated at 80° C. (internal temperature). The reaction was monitored periodically by TLC (9:1 heptane-ethyl acetate). After 5 hours the reaction appeared to be about 50% complete. After 17 hours the reaction was judged complete by TLC analysis. The reaction mixture was allowed to cool to room temperature and was then extracted with ether (5×100 mL). The extracts were dried over sodium sulfate and concentrated to give a yellow-orange solid. The crude solid was purified on silica gel (100 g) using 9:1 heptane-ethyl acetate. Fractions containing product were pooled and concentrated to give 1.4 g (57%) of the desired product as a yellow-orange solid. The structure was confirmed by 1H NMR analysis in DMSO-d6.

Provenance & Evidence