General Synthesis of Ketones from Carboxylic Esters and Carboxamides by Use of Mixed Organolithium‐Magnesium Reagents: Syntheses of Artemisia Ketone

Abstract
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 is illustrated by two direct syntheses of artemisia ketone (14).