Lithium phenylthio cuprate conjugate additions

Interesting and useful variations in R involve more complex alkyllithium reagents. For example, the treatment of (3-iodoenone (10) with lithium phenylthio(2-vinylcyclopropyl)cuprate gave the conjugate addition product (11) as an intermediate en route to the bicyclic dienone (12 82% equation 9).35 The ability of a cuprate to deliver a functionalized group to the enone was a definite advantage in this synthetic scheme. 

The use of the mixed lithium phenylthio(alkyl)cuprates, PhSCuRLi, for conjugate addition to a,p-un-saturated carbonyl compounds is well known. - The reaction of phenylthiocuprates derived from Grignard reagents with cinnamates and crotonates has also been reported (Scheme 50). ... 

CONJUGATE ADDITIONS Bis(methylthio)(trimethylsilyl)methyllithium. Diethylalum-inum cyanide. Di(a-methoxyvinyl)copperlithium. Ethyl diethoxyacetate. Ethyl methylsulfinylacetate. Lithium a-carboethoxy vinyl(l-hexynyl)cuprate. Potassium fluoride. Quinine, chinchonine. Titanium tetrachloride. Trimethylaluminum. Tris-(phenylthio)methyllithium. 

CONJUGATE ADDITION Diethyl acetylmethylmalonate. Dilithium trimethyl cuprate. N,N-Dimethylbenzeneselenenamide. Dimethyl sulfoxide. Lithium di-(2-vinylcyclo-propyl)cuprate. Lithium phenylthio(cyclopropyi)cuprate. Lithium phenylthio[(a-diethoxymethyl)vinyi]cuprate. 2-(2-Mcthoxy)-aIiylidene-l,3-dithiane. 2-Nitropropene. Tetra- -butylammonium fluoride. Titanium(IV) chloride -is(methyithio)methyl-lithium. 

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