Question

what is difference between coupling and cross coupling..??

Answer 1

cross coupling reactions are those which two different started materials each of which is easily and earth with and activation group are reacted together with the aid of metal press Travels the result is the loss of the two activation group and the formation of new covalent bond between the remaining fragments

Answer 2

A coupling reaction in organic chemistry is a general term for a variety of reactions where two hydrocarbon fragments are joined together with the aid of a metal catalyst. In one important reaction type a main group organometallic compound of the type RM (R = organic fragment, M = main group centre) reacts with an organic halide of the type R'X with formation of a new carbon-carbon bondin the product R-R' 

Cross-coupling reactions are those in which two different starting materials, each of which is usually endowed with an activating group, are reacted together with the aid of a metal catalyst. The result is the loss of the two activating groups and the formation of a new covalent bondbetween the remaining fragments.

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