Hydrochloric Acid → HCID 21279101, compound

Participants

Reaction Steps

To a stirred solution of 21 g 4-chloro-3-formyl-thiochrom-3-ene in 80 ml dry dimethylsulfoxide under nitrogen is added 15 g mercaptosuccinic acid. 36 ml triethylamine is then added dropwise and subsequently the reaction mixture is kept at 90°-100° C. for 30 minutes. The mixture is then diluted with water, acidified with hydrochloric acid and extracted with diethylether. The organic layer is then extracted with aqueous sodium bicarbonate solution. After acidification of the aqueous layer the product precipitates as a tar. It is taken up in chloroform. After evaporation of the solvent the residue is recrystallized from a mixture of chloroform and cyclohexane. Pure (4H-thieno[3,2-c][1]benzothiopyran-2-yl)acetic acid is obtained; m.p. 106°-110° C.

Provenance & Evidence