反应详情

(b)(i) Cysteamine hydrochloride (9.95 g) was dissolved in concentrated hydrochloric acid (50 ml) and the solution was cooled to 0°. 2-Hydroxymethylthiophene (10 g) was added dropwise to the stirred solution which was maintained at below 5°. The mixture was stirred overnight at room temperature, adjusted to pH 10 with concentrated aqueous sodium hydroxide and extracted with ethyl acetate. The extracts were evaporated and the residue was distilled at 158°-164°/760 mm Hg to give 2-(2-thienylmethylthio)-ethylamine which was converted into the hydrochloride, m.p. 108°-111°, by treatment with ethanolic HCl and ether.

1. temperaturethe solution was cooled to 0°
2. temperaturewas maintained at below 5°
3. extractionextracted with ethyl acetate
4. customThe extracts were evaporated
5. distillationthe residue was distilled at 158°-164°/760 mm Hg