Synthesis of 1,4-Dicarbonyl Compounds from Silyl Enol Ethers and Bromocarbonyls, Catalyzed by an Organic Dye under Visible-Light Irradiation with Perfect Selectivity for the Halide Moiety over the Carbonyl Group
作者:Naoto Esumi、Kensuke Suzuki、Yoshihiro Nishimoto、Makoto Yasuda
DOI:10.1021/acs.orglett.6b02869
日期:2016.11.4
We report the visible-light-induced radical coupling reaction of silyl enol ethers with α-bromocarbonyl compounds to give 1,4-dicarbonyls. The reaction was effectively accelerated using an inexpensive organic dye (eosin Y) as a photoredox catalyst. 1,4-Dicarbonyl compounds alone were afforded, without the generation of carbonyl adducts of the α-halocarbonyls, which are usually generated in the presence
我们报道了可见光诱导的甲硅烷基烯醇醚与α-溴羰基化合物的自由基偶联反应,得到1,4-二羰基。使用廉价的有机染料(曙红Y)作为光氧化还原催化剂可有效地促进反应。仅提供1,4-二羰基化合物,而没有生成α-卤代羰基的羰基加合物,α-卤代羰基的羰基加合物通常是在氟阴离子或路易斯酸的存在下生成的。将多种甲硅烷基烯醇醚,α-溴代酮,α-溴代酸酯和α-溴代酰胺应用于该系统以产生偶联化合物。