Concise Synthesis of <font>α</font>-(Hydroxymethyl) Alkyl and Aryl Vinyl Ketones
作者:Jihène Ben Kraïem、Hassen Amri
DOI:10.1080/00397911.2011.592626
日期:2013.1.1
first been reported as starting materials for the synthesis of a new class of α-hydroxymethyl-α,β-unsaturated ketones 3. Thus, under heterogeneous liquid–liquid medium in the presence of concentrated aqueous potassium carbonate as a base, both aliphatic and aromatic 2,4-dioxoalkanoates 2 react with aqueous formaldehyde to afford the corresponding ketones 3 in fair to good yields. GRAPHICAL ABSTRACT
these challenges rationally in the case of the enzymatic synthesis of methyl 3‐hydroxy‐2‐methylpropanoate (commonly denoted as the Roche ester) and derivatives thereof using the ene reductase YqjM. By a highly efficient, concept‐based approach of designing mutant variants of YqjM and engineering substrates we could alter both the rate constant and the enantioselectivity of the reaction. Preparative scale
A direct synthesis of α-(hydroxymethyl) and α-alkyl-vinyl alkyl ketones
作者:Jihène Ben Kraïem、Taïcir Ben Ayed、Hassen Amri
DOI:10.1016/j.tetlet.2006.07.093
日期:2006.9
Reaction of 2,4-diketoesters 3a–c with aqueous formaldehyde using potassium carbonate solution as base affords the corresponding α-methylene-β-hydroxyalkanones 4a–c which provide a route to α,β-unsaturated alkyl ketones 6a–e via coupling of α-acetoxymethyl alkyl vinyl ketone 5a with Grignardreagents in the presence of a catalytic amount of LiCuBr2 at low temperature.