Gilman reagent conjugate carbonyl addition

Coniine, molecular model of. 28 structure of, 294 Conjugate acid, 49 Conjugate base, 49 Conjugate carbonyl addition reaction, 725-729 amines and, 727 enamines and, 897-898 Gilman reagents and, 728-729 mechanism of, 725-726 Michael reactions and, 894-895 water and. 727 Conjugated diene, 482... 

Gilman reagents undergo conjugate addition with a,j8-unsaturated carbonyl compounds in a reaction that is closely related to the Michael reaction. 

Hahdes of transition metals react with methyllithium to give methyl compounds. This reaction is alternatively afforded by organocopper compounds hke hthiumdialkylcuprates which are also known as Gilman reagents. These reagents are widely used for nucleophilic substitutions of epoxides, alkyl hahdes and for conjugate additions to a,p-unsaturated carbonyl compounds by methyl anion. 

Kharasch and Tawney (1941) reported that copper salts catalyze 1,4-addi-tion of Grignard reagents to a,jS-unsaturated ketones. Gilman et al. (1952) first discovered that phenylcopper reacts with benzalacetophenone in a 1,4-addition. Subsequently House and associates (1966) have revealed the scope of the conjugate addition of cuprate complexes. Now alkyl, vinyl, and aryl groups can be introduced specifically at the p position of a,jS-unsaturated carbonyl compounds. Transfer of an allyl group from lithium diallylcuprate to 2-cyclohexenone is also known (House and Fischer, 1969). However, ethynyl, cyano, and hetero groups attached to the copper atom are difficult to transfer to electron-poor olefins. 

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