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Abstract: A selective methodology for the synthesis of either 3-cyanoindoles or 4-cyanoquinolines via a base-modulated palladium-catalyzed reductive N-heterocyclization from a common 1-cyano-1-(2-nitrophenyl)-1-alkene precursor is described. The required starting materials were prepared either by a Kosugi–Migita–Stille coupling of 2-halo-1-nitrobenzenes with a tributyl(1-alkenyl)stannane or by a vicarious nucleophilic substitution (VNS) of nitrobenzenes followed by a Knoevenagel condensation with an aldehyde. [Copyright &y& Elsevier]

Sequential treatment of alkyl 2-(2-nitroaryl)-2-butenoates with potassium tert -butoxide and an electrophile, such as methyl iodide, benzyl bromide and allyl bromide, afforded N -alkoxyindoles. In related reactions, using sodium tert -pentoxide as the base with or without in situ addition of an electrophile afforded N -alkoxy- and N -hydroxyindoles, respectively. Electrophiles such as dimethylsulfate, p- tosyl chloride, and acetic anhydride afforded moderate yields of the respective N -methoxy-, N -tosyloxy, and N -acetoxyindoles, while methyl iodide, benzyl bromide, and 1-bromohexane failed to form alkylated products using sodium tert -pentoxide as the base. [Display omitted] [ABSTRACT FROM AUTHOR]