Enantioselective Synthesis of 3-Amino-3’-carbazole Oxindole Derivatives via Friedel-Crafts Aminoalkylation Reaction

Organocatalytic Friedel-Crafts aminoalkylation reaction is demonstrated in this study for the construction of biologically important hybrid molecular architectures of carbazole containing 3-amino oxindoles using bifunctional cinchonidine derived thiourea organocatalyst. The Friedel-Crafts functionalization of 4-hydroxy carbazole with isatin derived ketimines well performed with a wide range of substrates resulted in excellent yields (up to 95 %) and enantioselectivities (up to 99 % ee) of the desired products. A minimal catalyst loading (0.5 mol%) was utilized at ambient temperatures under mild reaction conditions.