organocpper (I) reagents
the reaction of an organnolithium compound with a copper (I) halide gives organocopper species, which, depending on the proportion of reagents used, correspond to the empirical formulae RCu and R2CuLi.
các bạn tham khảo sách "guidebook to organic synthesis" 2nd edition
RK MACKIE, D M SMITH & R A AITKEN
nói tóm lại là như sau :
R-X +Li ----> RLi +LiX
2RLi + CuX ----> R2CuLi + LiX
R2CuLi +R'X ----> R-R' + RCu + LiX
chú ý :
R bậc 1 or 2
R' bậc 1