Lithium dialkylcuprates reactions with carbonyl compounds

The principal synthetic application of lithium dialkylcuprate reagents IS their reaction with a 3 unsatu rated carbonyl compounds Al kylation of the 3 carbon occurs... 

Selenium-stabilized carbanions can be also generated by 1,4-addition of nucleophilic reagents to a-selanyl a,[3-unsaturated carbonyl compounds. The conjugate addition of trialkylsilyllithium compounds to 133, followed by reaction with allyl iodide, afforded the addition products 134 with good m-stereoselectivity (R = Me dr 86 14 R = Ph dr 94 6) (Scheme 34).214 The addition of lithium dialkylcuprates to 2-phenylselanylcycloalk-2-enones has also been used for the synthesis of natural products.215,216... 

The analogy extends toward their reaction with lithium dialkylcuprates. Just as alkyl halides react with lithium dialkylcuprates to form carbon-carbon bonds, so do a,p-unsaturated carbonyl compounds. 

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