氯霉素衍生噁唑烷酮的合成及其在Aldol反应中的不对称诱导作用

Synthesis of Oxazolidinone Derivative from Chloramphenicol and Its Asymmetric Induction in Aldol Reaction

以氯霉素为原料,经五步反应合成了一种新的噁唑烷酮手性辅基,考察了其在不对称aldol反应中的手性诱导作用.在Ti Cl4/N,N'-四甲基乙二胺(TMEDA)存在下,带有该辅基的酰亚胺烯醇供体可与芳香醛、脂肪醛和α,β-不饱和醛等多种醛顺利反应,以较高的产率(>80%)和非对映选择性(dr≥19∶1)生成Evans型syn-aldol反应产物.

A new oxazolidinone chiral auxiliary was prepared from chloramphenicol in 5 steps. Aldol reactions between enolates bearing this auxiliary and varied aldehydes in the presence of Ti Cl4/N,N＇-tetramethylethalenediamine（TMEDA） were found to proceed in high yield（80%） and diastereoselectivity（dr≥19∶1） to give Evans syn-aldol adducts.