New reactions of hydrazides. Part 1: Directed ortho- and lateral metalation of aromatic carbocyclic and heterocyclic systems

Abstract Aromatic and heterocyclic 2,2-dialkylhydrazides undergo directed metalation with 2 equivalents of n -, s - or t -BuLi, and the resulting C,N-dilithio species react with a variety of electrophiles. The products may be readily converted to the corresponding carboxylic acids or esters by oxidation with manganese dioxide in water or methanol containing acetic acid.