A General Procedure for the Synthesis of 1,3-Bis(indolyl) Compounds via Michael­ Addition Catalyzed by InBr₃/TMSCl

Abstract

A new facile entry to the synthesis of 1,3-bis(indol-3-yl)butane-1-ones is presented. The procedure effectively utilizes a InBr₃/TMSCl mixture (10 mol%) as a promoter for the chemoselective Michael addition of variously functionalised indoles to α,β-unsaturated indolyl ketones. The excellent yields and the mildness of the experimental conditions guarantee a widespread applicability of the protocol towards the construction of functionalised keto-bis(indolyl) compounds.

catalysis - enones - indium - indoles - Michael additions

References

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