Gold‐Catalyzed Oxa‐Povarov Reactions for the Synthesis of Highly Substituted Dihydrobenzopyrans from Diaryloxymethylarenes and Olefins |
| |
| Authors: | Vinayak Vishnu Pagar Chang‐Chin Tseng Prof?Dr Rai‐Shung Liu |
| |
| Institution: | Department of Chemistry, National Tsing Hua University, Hsinchu, 30013 (Taiwan), Fax: (+886)?3‐5711082 |
| |
| Abstract: | Oxa‐Povarov reactions involving readily available diaryloxymethylarenes and aryl‐substituted alkenes are reported. Their 4+2] cycloadditions were efficiently catalyzed by IPrAuSbF6 (IPr=1,3‐bis(diisopropylphenyl)imidazol‐2‐ylidene) with high diastereoselectivity. Product analysis revealed that the reactions likely proceed by a stepwise ionic mechanism, because both E‐ and Z‐configured β‐methylstyrene gave the same cycloadducts in the same proportions. |
| |
| Keywords: | cycloaddition diastereoselectivity gold oxygen heterocycles synthetic methods |
|
