Lewis acid-catalyzed reactions of .alpha.,.beta.-unsaturated N,N-dimethylhydrazones with 1,4-benzoquinone. Formation of indoles by a novel oxidative rearrangement
The reaction of 1-ethoxycarbonylindole-3-carboxaldehyde N,N-dimethyl-hydrazone with five dienophiles has been studied, and the first use of this new azadiene in a Diels-Alder reaction with N-methylmaleimide has been achieved leading to a new synthesis of an [a]annellated gamma-carboline.
Lewis acid-catalyzed reactions of .alpha.,.beta.-unsaturated N,N-dimethylhydrazones with 1,4-benzoquinone. Formation of indoles by a novel oxidative rearrangement
作者:Antonio M. Echavarren
DOI:10.1021/jo00301a009
日期:1990.7
STUDY OF THE REACTIONS OF FOUR INDOLIC 1-AZADIENES WITH A FEW ENOIC, YNOIC, AND AZO DIENOPHILES
ABSTRACT Four indolic 1-azadienes (1a–c, 2) underwent Diels–Alderreaction, dienophile-catalysed addition–elimination reaction, Michael reaction or hydrolysis with three enoic, two ynoic and one azo dienophiles, leading to a γ-carboline, various 3-cyanoindoles, 3-formylindole and several nitrones.