Chiral Urea-Catalyzed Asymmetric Mannich Reaction of 3-Fluorooxindoles with α-Amidosulfones: Synthesis of Optically Active α-Fluoro-β-amino-oxindoles

Abstract

The asymmetric Mannich reaction of 3-fluorooxindoles and α-amidosulfones catalyzed by a chiral urea catalyst derived from quinine in presence of K₃PO₄ was developed. Through the asymmetric reaction, a series of α-fluoro-β-amino-oxindoles, containing a tertiary carbon stereocenter, could be obtained in high yields (up to 95%) with high enantioselectivity (95%) and diastereoselectivity (>99:1). Such α-fluoro-β-amino-oxindole compounds are expected to become candidates in the field of medicine.

Key words

Mannich reaction - 3-fluorooxindoles - α-fluoro-β-amino-oxindoles - quinine-derived skeleton - urea-catalyzed catalysts

Publication History

Received: 18 November 2021

Accepted after revision: 20 January 2022

Accepted Manuscript online:
20 January 2022

Article published online:
09 February 2022

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