Regioselective Opening of Chalcone Epoxides with Nitrogen Heterocycles Using Indium(III) Chloride as an Efficient Catalyst

Abstract

Indium(III) chloride catalyzes regioselective ring opening of chalcone epoxides with nitrogen heterocycles such as indole, 2-methyl indole, and pyrrole under mild conditions at room temperature to afford 1,3-diaryl-2-hydroxy-3-(1H-3-indolyl/2-pyrrolyl)propan-1-ones in good yields (60–88%) within 20–50 min.

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GRAPHICAL ABSTRACT

Keywords:

• Chalcone epoxide
• 1,3-diaryl-2-hydroxy 3-(1H-3-indolyl/2-pyrrolyl)propan-1-one
• InCl₃
• indole
• pyrrole

ACKNOWLEDGMENT

N. K. K. thanks the Council of Scientific and Industrial Research, New Delhi, for the award of a junior reaserch fellowship (NET).

Notes

^a 1 equiv of epoxide and 1 equiv indole were used.

^b Isolated yield.

^c Catalyst 10 mol % used.

^d Catalyst 20 mol % used.