2-Chloroethyl chloroformate → Thiomorpholine 1,1-dioxide hydrochloride

Participants

Reaction Steps

2-Chloroethyl chloroformate (0.72 ml, 6.7 mmol) was added dropwise to a solution of 4-methylthiomorpholine-1,1-dioxide (1.0 g, 6.7 mmol) in toluene (10 ml) at 0° C. under N2. After 10 min, the reaction was warmed and maintained at reflux for 2 h. On cooling, the reaction mixture was evaporated and partitioned between EtOAc and H2O. The organic layer was separated and washed sequentially with dilute HCl and saturated brine, then dried over Na2SO4 and evaporated. The residue was taken up in MeOH (10 ml) and heated at reflux for 2 h, after which time the mixture was evaporated and triturated with EtOAc to afford the subtitle compound (415 mg, 36%) as a solid. Rf 0.34 (CH2Cl2/MeOH/0.88 NH3 90/10/1, v/v). MS m/z 136 (MH+).

Provenance & Evidence