1CH3CH2Cl → (CH3CH2)2LiCu → CH3CH2CH2CH3
A B
reagent for A → 1. Li/Ether 2. CuI
reagent for B → CH3CH2Cl
(CH3)2CHBr → [(CH3)2CH]2LiCu→(CH3)2CHCH2CH2CH3
C D
Reagent for C → 1. Li 2. Cu
REagent for D → CH3CH2CH2Br
in abv two reactions After A Lithiumdiethylcuprate and after C Lithium diisopropylcuprate is formed
Lithium Dialkyl cuprate are also called Gilmann's reagent
IN GENERAL
R-X → RLi → R2LiCu → R - R' + RCu + LiX
E F G
for E reagent is Li , diethyl ether
for F reagent is CuI
For G reagent is R' X ( R' shuld be methyl, 1° alkyl or 2 cycloalkyl )
R2CuLi as mentioned is Gilmaan's reagent
[ note : R' may be equal to R ]
