direct annulative coupling of 3-(acetylamino)thiophenes with internal alkynes proceeds smoothly under rhodium catalysis through acetylamino-directed C–H bond cleavage at the C2-position, leading to the effective construction of 4-acetylthieno[3,2-b]pyrrole derivatives. The acetyl directing group on the annulation product is readily removed to produce the 4-unprotected thieno[3,2-b]pyrrole derivative
3-(乙酰氨基)噻吩与内部炔烃的直接环偶联在铑催化下通过乙酰氨基定向的 C-H 键在 C2 位断裂顺利进行,从而有效构建 4-乙酰噻吩并 [3,2- b ]吡咯衍生物。环化产物上的乙酰基导向基团很容易被去除,产生 4-未保护的噻吩并 [3,2- b ] 吡咯衍生物。
Gol'dfarb et al., Doklady Akademii Nauk SSSR, 1959, vol. 126, p. 86