Enantioselective Halocyclization Of Indole Derivatives: Using 1,3-Dihalohydantoins With Anionic Chiral Co(Iii) Complexes

Highly enantioselective halocyclization reactions of indole derivatives, including tryptophols and tryptamines, have been accomplished by means of anionic chiral Co(III) complexes and 1,3-dihalohydantoins (as little as 0.50 equiv). 3-Halo-fused indolines were obtained in excellent yields (up to 98%) and enantioselectivities (up to 98% ee), employing the chiral anion phase-transfer-catalysis strategy.