Hydrogen Bromide → HCID 86734372, compound

Participants

Reaction Steps

A solution of 1'-ethyl-4-methoxythioxanthene-9-spiro-4'-piperidine (1.625 g.) in glacial acetic acid (20 ml.) is added to 48% w/v hydrobromic acid (20 ml.) and refluxed with stirring for 5 hours. The mixture is cooled, diluted with water (500 ml.), cooled in ice and basified with 19N-sodium hydroxide solution and the solution washed with ether (× 3). The aqueous alkaline layer is acidfied to pH 1 with concentrated hydrochloric acid, neutralised with solid sodium bicarbonate and extracted with ethyl acetate (× 3). The combined ethyl acetate extracts are washed with water (× 3), dried over MgSO4 and the ethyl acetate removed by distillation in vacuo. The resulting sticky solid is triturated with ether to give 1'-ethyl-4-hydroxythioxanthene-9-spiro-4'-piperidine, m.p. 223°-225° C. on recrystallisation from dimethyl formamide/methanol/water.

Provenance & Evidence