Efficient selective synthesis of 2-substituted indoles from complex-base-promoted arynic cyclisations

Abstract

2-Substituted indoles have been efficiently obtained by selective arynic cyclisation of halogenated aryl imines of methyl ketones in the presence of the complex-base NaNH₂–Bu^tONa and by PhCH₂SH–AlCl₃ opening of tetrahydrothiopyranoindoles also obtained from arynic cyclisation of imines.