Regioselective Synthesis of Functionalized Furans by Cyclization of 1,3-Bis-Silyl Enol Ethers with 1-Chloro-2,2-dimethoxyethane
作者:Esen Bellur、Helmar Görls、Peter Langer
DOI:10.1002/ejoc.200400805
日期:2005.5
Cyclization of 1,3-bis-silyl enol ethers with 1-chloro-2,2-dimethoxyethane allowed an efficient, regio- and diastereoselective synthesis of a variety of 2-alkylidene-4-methoxytetrahydrofurans. The TFA-mediated elimination of methanol resulted in the formation of functionalized furans. Similarly, 2,3,3a,4,5,6-hexahydro-2,3-benzofurans were prepared and transformed into 4,5,6,7-tetrahydro-2,3-benzofurans
1,3-双-甲硅烷基烯醇醚与 1-氯-2,2-二甲氧基乙烷的环化允许高效、区域和非对映选择性合成各种 2-亚烷基-4-甲氧基四氢呋喃。TFA 介导的甲醇消除导致功能化呋喃的形成。类似地,制备了 2,3,3a,4,5,6-六氢-2,3-苯并呋喃,并通过用 TFA 处理转化为 4,5,6,7-四氢-2,3-苯并呋喃。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)