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Synthesis of ( E )‐1‐Propenyl Ketones from Carboxylic Esters and Carboxamides by Use of Mixed Organolithium‐Magnesium Reagents. Synthesis of α‐Damascone, β‐Damascone, and β‐Damascenone
Author(s) -
Fehr Charles,
Galindo José
Publication year - 1986
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19860690127
Subject(s) - chemistry , propenyl , reagent , lithium (medication) , magnesium , organic chemistry , combinatorial chemistry , medicine , endocrinology
The novel reagents formed by combination of allylmagnesium chloride and a strong non‐nucleophilic lithium base (LiNR 2 ) convert non‐ or slowly enolizable carboxylic esters or carboxamides into 2‐propenyl ketones which are protected from further reaction by their in situ conversion into enolates. This modified Grignard reaction is applied to efficient syntheses of α‐damascone, β‐damascone, β‐damascenone, and various other ( E )‐1‐propenyl ketones.