Lithium diisopropylamide (LDA) (or s-BuLi/TMEDA) in diethyl ether promotes smooth ring opening of oxazolinyl alkyl oxiranes to give oxazolinyl allylic alcohols, which are masked Baylis-Hillman adducts, in good to excellent yields. An E2-E1cb-like syn-beta-elimination is proposed to explain the easy base-promoted isomerization of the studied oxiranes.
二
乙醚中的
二异丙基氨基化
锂(
LDA)(或s-BuLi / TME
DA)促进了
恶唑啉基烷基氧杂
环丁烷的平滑开环,生成
恶唑啉基烯丙基醇,这是被掩盖的Baylis-Hillman加合物,收率良好或优异。提出了一种E2-E1cb样的syn-beta消除方法,以解释所研究的
肟基的易于碱促进的异构化。