Indol-2-ylcopper reagents

Indol-2-ylcopper reagents can also be prepared from 2-lithioindoles and they have some potential for the preparation of 2-substituted indoles. 1-Methyl-indol-2-ylcopper can be prepared by reaction of 2-lithio-l-methylindole with CuBr[10]. It reacts with aryl iodides to give 2-aryl-1-methylindoles. Mixed cyanocuprate reagents can be prepared using CuCN[ll], The cyan-ocuprate from 1-methylindole reacts with allyl bromide to give 2-allyl-l-methylindole. 

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