Reaction of 4-t-butyldimethylsiloxy-1-benzopyrylium salt with enol silyl ethers and active methylenes
作者:Hideharu Iwasaki、Takashi Kume、Yohsuke Yamamoto、Kin-ya Akiba
DOI:10.1016/s0040-4039(01)91372-3
日期:1987.1
4-t-Butyldimethylsiloxy-l-benzopyrylium salt () was prepared in situ from chromone () and t-butyldimethylsilyl trillate and the salt reacted with enol silyl ethers, ketene silyl acetals and active methylene compounds to afford 2-substituted 4-t-butyldimethylsiloxy-2H-1-benzopyrans () in high yield. These products reacted with acid chlorides and an iminium salt to give 2,3-disubstituted 2,3-dihydro-
由色酮()和叔丁基二甲基甲硅烷基三甲酸酯原位制备4-叔丁基二甲基甲硅烷氧基-1-苯并benzo鎓盐(),并使该盐与烯醇甲硅烷基醚,乙烯酮甲硅烷基乙缩醛和活性亚甲基化合物反应,得到2-取代的4-叔丁醇丁基二甲基甲硅烷氧基-2H-1-苯并吡喃(),收率高。这些产物与酰氯和亚胺盐反应,得到2,3-二取代的2,3-二氢-4H-1-苯并吡喃-4-酮。