Delocalized Nitrogen Carbanions in SRN1 Reactions

Article abstract of DOI:10.1021/jo00129a048

S_RN1 reactions can be performed with nitrogen carbanions as nucleophiles, and generally the reaction leads to a mixture of isomers.In the case of the pyrrolyl anion, position 2 is about four times more reactive than position 3.When the ortho positions of pyrrole are substituted by alkyl groups, the reactivity of position 2 increases while that of position 3 decreases.With tert-butyl groups as the substituents, no reaction at position 2 is observed.With the indolyl anion as the nucleophile, no substitution at position 2 or at the phenyl ring is observed, and only one product corresponding to monosubstitution at position 3 is obtained.Imidazolyl anions react preferentially at position 4 (5), and substitution of position 2 by a methyl group makes the coupling regioselective.