From Carbamate to Chalcone: Consecutive Anionic Fries Rearrangement, Anionic Si → C Alkyl Rearrangement, and Claisen-Schmidt Condensation.
Singam Naveen KumarSuhas Ravindra BavikarChebolu Naga Sesha Sai Pavan KumarIsaac Furay YuRong-Jie CheinPublished in: Organic letters (2018)
A highly efficient one-pot procedure was developed for the synthesis of various 2'-hydroxychalcones from phenyl diethylcarbamate, featuring consecutive Snieckus-Fries rearrangement, anionic Si → C alkyl rearrangement, and Claisen-Schmidt condensation in a single operation. The applicability of this protocol was demonstrated by the highly efficient synthesis of the anti-inflammatory natural product lonchocarpin. The mechanism insight is also provided.