Methane derivatives, carbon acidity-carbanion

A further interesting consequence follows in the case of carbon acids where acidity is induced by a -h substituent. In the conjugate base of such an acid, the carbanion interacts with the -h E substituent to form an odd conjugated system isoconjugate with an odd AH anion. Such an ambident anion can react with a proton at more than one point, so protonation may lead to an isomer of the original methane derivative. 

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