反应详情

A solution of compound (Z)-3-dimethylamino-2-isocyano-acrylic acid ethyl ester (11.8 g, 79 mmol) and 3-bromo aniline (11.3 g, 65 mmol) in n-butanol (90 mL) was heated to reflux for 72 h [reaction was monitored by TLC]. Reaction mixture was concentrated under reduced pressure to remove n-butanol and the residue was passed through silica gel column, eluated with a mixture of ethyl acetate and hexane to give a mixture of ethyl and n-butyl ester compounds which was then separated by flash column chromatography over silica gel using 3:7 mixture ethyl acetate and hexane as eluant. Finally the ethyl ester was further purified by crystallization to furnish 3 (2.5 g, 13%) as a brown solid. HRMS (ESI+): m/z=295.1349 [M+H]

1. temperatureto reflux for 72 h
2. custom[reaction was monitored by TLC]
3. customReaction mixture
4. concentrationwas concentrated under reduced pressure
5. customto remove n-butanol
6. additioneluated with a mixture of ethyl acetate and hexane
7. customto give
8. customwas then separated by flash column chromatography over silica gel using 3:7 mixture ethyl acetate and hexane as eluant
9. customFinally the ethyl ester was further purified by crystallization