Copper-Catalyzed Coupling of 2-Siloxy-1-alkenes and Diazocarbonyl Compounds: Approach to Multisubstituted Furans, Pyrroles, and Thiophenes
作者:Wei Wen Tan、Naohiko Yoshikai
DOI:10.1021/acs.joc.6b00904
日期:2016.7.1
We report herein copper(II)-catalyzed cyclization reactions of silylenolethersderivedfrom methyl ketones with α-diazo-β-ketoesters or α-diazoketones to afford 2-siloxy-2,3-dihydrofuran derivatives or 2,3,5-trisubstituted furans, respectively, under mild conditions. The former cyclization products serve as versatile 1,4-diketone surrogates, allowing facile preparation of 2,3,5-trisubstituted furans
An efficient protocol for the synthesis of furans through Rh(III)-catalyzed vinyl C–H activation from acrylic acids and α-diazocarbonyl compounds has been developed. The reaction features broad functional group tolerance and affords a series of furans in moderate to good yields. Moreover, no additives such as copper or silver salts are required. Some control experiments are performed to give insight