Preparation by the Direct Insertion of Activated Copper

Copyright 2005 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-31131-9 

Its reaction with benzaldehyde provides the desired homoallylic alcohol 4 in 96% yield [8]. An improved procedure allowing the generation of an exceptionally active copper(O) reagent is obtained by the low-temperature reduction of lithium 2-thienylcyanocuprate 5 with lithium naphthalenide [9]. In this case, 1,4-additions to enones in the presence of MejSiCl [10] proceed especially well. 

Cut LiCl with lithium naphthalenide, it is possible to prepare allylic copper species that undergo smooth addition to enones leading to the 1,4-addition product such as 8 in 92% yield [11], Remote ester-functionalized aryl- and alkyl-copper compounds can be readily prepared by this method [12], Remarkably stable ortho-halophenylcopper reagents obtained by the direct insertion of activated copper undergo substitution reactions with alkyl iodides, benzylic bromides and various acid chlorides [13,14]. 

Perfluoroalkylcopper reagents have received more attention than perhaps any other perfluorinated organometallic compounds. They can be prepared from per-fluoroalkyl iodides and copper metal in polar solvents (such as DMSO, DMS, 

Preparation of Functionalized Copper Reagents Starting from Oiganolithium Reagents 

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