Aggregative activation and heterocyclic chemistry I complex bases promoted arynic cyclisation of imines or enaminoketones; regiochemical synthesis of indoles

Article abstract of DOI:10.1016/S0040-4020(01)89304-2

The complex base NaNH₂-t-BuONa allowed expeditious syntheses of indoles by arynic cyclisation of imines or enaminoketones prepared from halogeno anilines and carbonyl derivatives. Unstable imines may be used without purification, complex bases being unsensitive to impurities. It is showed that this kind of reaction may be applied to mixture of substrates suitably halogenated on the benzene ring. Formation of three components aggregates is proposed to explain a number of observations.