General Synthesis of Ketones from Carboxylic Esters and Carboxamides by Use of Mixed Organolithium-Magnesium Reagents: Syntheses of Artemisia Ketone
作者:Charles Fehr、Jos� Galindo、Roland Perret
DOI:10.1002/hlca.19870700710
日期:1987.11.4
The novel reagents formed by combination of Grignard reagents (RMgX) with lithium diisopropylamide (LDA) convert non-enolizable or slowly enolizable carboxylic esters or caboxamides into ketones which are protected from further reaction by their in situ conversion into enolates. These enolates can be trapped with electrophiles such as Me3SiCl and allyl bromide. The scope of this Grignard mono-addition
由格氏试剂(RMgX)与二异丙基氨基化锂(LDA)结合形成的新型试剂可将不可烯化或缓慢可烯化的羧酸酯或羧酰胺转化为酮,可通过原位转化为烯醇酸酯来防止其进一步反应。这些烯醇化物可以被亲电试剂(例如Me 3 SiCl和烯丙基溴)捕获。这种格氏试剂单加成的范围由蒿蒿酮的两种直接合成方法说明(14)。