Rhodium-Catalyzed Direct Annulation of Aldehydes with Alkynes Leading to Indenones: Proceeding through <i>in Situ</i> Directing Group Formation and Removal
作者:Shuyou Chen、Jintao Yu、Yan Jiang、Fan Chen、Jiang Cheng
DOI:10.1021/ol4021145
日期:2013.9.20
The Rh-catalyzed direct annulation of an aldehyde with an alkyne leading to indenone was achieved. The in situ temporal installation of acetylhydrazine enables the annulation of the ortho arene C-H bond with alkynes to form ketone hydrazone. Subsequently, the in situ directing group removal takes place since ketone hydrazone is more susceptible toward hydrolysis than aldehyde hydrazone. Notably, this procedure tolerates a series of functional groups, such as methoxyl, acetylamino, fluoro, trifluoromethyl, methoxycarbonyl, chloro, and bromo groups.