文章基本信息

标题：Ring-Opening Cyclization of Spirocyclopropanes Using Sulfoxonium Ylides
本地全文：下载
作者：Yuta Onuki ; Hisanori Nambu ; Takayuki Yakura 等
期刊名称：Chemical and Pharmaceutical Bulletin
印刷版ISSN：0009-2363
电子版ISSN：1347-5223
出版年度：2020
卷号：68
期号：5
页码：479-486
DOI：10.1248/cpb.c20-00132
出版社：The Pharmaceutical Society of Japan
摘要：Ring-opening cyclization of cyclohexane-1,3-dione-2-spirocyclopropanes using dimethylsulfoxonium methylide proceeded regioselectively to produce 2,3,4,6,7,8-hexahydro-5 H -1-benzopyran-5-ones in good to high yields. The reactions of cycloheptane- and cyclopentane-1,3-dione-2-spirocyclopropanes could construct [7.6]- and [5.6]-fused ring systems. This reaction was also carried out using sulfoxonium ethylide, butylide, and benzylide, resulting in the formation of the corresponding 2,3- trans -disubstituted products in good to high yields, and it was shown that the dimethyl group can act as a dummy substituent. It was found that the 2- and 3-phenyhexahydrobenzopyran-5-ones can be readily converted into 5-hydroxyflavan and 5-hydroxyisoflavan, respectively.
关键词：sulfoxonium ylide;spirocyclopropane;ring-opening cyclization;flavan;isoflavan