Antimony Trichloride–Catalyzed Michael Addition of Indoles to the α,β‐Unsaturated Ketones

Abstract

Indoles undergo conjugate addition with α,β‐unsaturated ketones in the presence of a catalytic amount of antimony trichloride under refluxing condition to afford the corresponding Michael adduct in excellent yields. The substitution on the indole ring occurred exclusively at 3‐position without a trace of any N‐alkylated products.

Keywords:

• antimony trichloride
• conjugate addition
• indoles
• α,β‐unsaturated ketones

Acknowledgment

P. K. thanks Jadavpur University, Kolkata, for awarding the Junior Research Fellowship.