The Reformatsky reaction has been examined using a mild and effective method of electrochemical zinc activation, based on the cathodic reduction of a catalytic amount of zinc bromide in acetonitrile.
A Reformatsky-type reaction has been developed using iron catalysis in acetonitrile or DMF. Reduction of iron(II) bromide by manganese metal in acetonitrile provides a low-valent iron catalyst, which is the active species; under these conditions, α-chloroesters or nitriles can both be converted into their corresponding derivatives. The method was applicable to both ketones and aldehydes, resulting in the formation of β-hydroxyesters under mild conditions.
Coupling reactions of α-chloroesters with aryl halides (α-arylation) or carbonyl compounds (Reformatsky) using nickel catalyst allow, under mild conditions, the preparation of various functionalized aryl propionic acid derivatives or β-hydroxyesters. In the synthesis of aryl propionic acid derivatives, the process is efficient with aryl halides bearing either electron-withdrawing or electron-donating
Comportement de composes stanniques derives de β hydroxyesters: mise en evidence d'une reaction de retrocondensation et de la formation de β lactones
作者:Patrick Didier、Jean-Claude Pommier
DOI:10.1016/s0022-328x(00)84723-3
日期:1978.5
Organotin derivatives of β-hydroxyesters give rise upon heating to a retrocondensation reaction leading to the ketone and an α-organotin ester. Besides this reversible process, the reaction can follow another route, namely the formation of a β-lactone and of the alkenes coming from its decomposition.