四取代硼酸盐的1,2-氧迁移反应在环醚合成中的应用

The construction of cyclic ethers via a 1,2-oxygen migration reaction of boron ate-complex

本文应用四取代硼酸盐(boron ate-complex)分子内1,2氧迁移反应合成环醚。在本反应中,含羰基的有机硼烷在碱的作用下发生分子内亲核反应构建boron ate-complex,然后该复合物发生两次1,2氧迁移反应合成环醚。该方法反应时间短、条件温和、收率高且不需任何催化剂,另一方面为构建碳-氧杂环提供了新方法,本文应用该方法完成了苯基-(2-四氢呋喃)甲酮和苯基-(2-四氢-2H-吡喃)甲酮的合成。

A new method for the synthesis of cyclic ethers via 1,2-O-migration of boron ate-complex was establish-ed.Using carbonyl containing boron compounds as the substrates,LDA induced enolate formation followed by in-tramolecular addition with boron provided boron ate-complex intermediates.These intermediates underwent a quickly 1,2-O-migration initiated reaction sequence to furnish cyclic ethers.The reaction provided a mild and effective method for the construction of O-heterocyclic compounds.Based on this reaction,phenyl（ tetrahydrofuran-2-yl） methanone and phenyl（ tetrahydro-2 H-pyran-2-yl） methanone were successfuly synthesized with good yields.