摘要：

The selectivity and/or reactivity of organyl group transfer of mixed diorganocuprates in their alkyl coupling in THF depends on N- or O-donor solvents as cosolvents. Selective n-Bu group transfer is observed in room temperature alkylation of Grignard reagent derived stoichiometric n-BuPhCuMgBr reagent in THF:cosolvent and solvation effects do not change the group transfer ability. However, in the alkylation of catalytic mixed cuprates derived from CuI catalyzed n-BuPh~2ZnMgBr and n-Bu_2PhZnMgBr, group transfer ability depends on the solvation effect and it can be controlled by using N- or O-donor solvents. In alkylation of CuI catalyzed mixed zincate n-BuPh _2ZnMgBr and also n-Bu_2PhZnMgBr in THF at reflux temperature Ph group transfer takes place (n-Bu/Ph transfer ratio is 1:9 and 4:6, respectively) whereas n-Bu transfer increases in THF:NMP (1:1) resulting n-Bu/Ph transfer ratio of 4:6 and 8:2, respectively. Group transfer ability in allylation of n-BuPhZn seems not to be solvent dependent. The solvent effect on the group transfer ability has been found to be dependent also on the R 1 and R2 partnership in room temperature benzoylation of catalytic mixed cuprates, R~1R~2CuZnI, derived from CuI catalyzed R~1R~2Zn. These results are briefly discussed in terms of solvation of mixed diorganocuprate and diorganozinc reagents and provide useful information in their atom-economic alkyl, allyl and acyl coupling reactions.

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