Synthesis of Chiral Benzofuran-Derived β-Amino Esters Induced by N-tert-Butanesulfinamide

Abstract

The benzofuran skeleton is commonly found in a wide variety of natural products that display a wide range of biological activities. For this reason, benzofuran has a high potential for use as a scaffold in both chemical and pharmaceutical syntheses of natural products. This work describes the development of a novel asymmetric synthetic method of benzofuran-derived β-amino esters via K₂CO₃-promoted domino reactions of ortho-hydroxyl aromatic N-tert-butylsulfinyl imines and diethyl bromomalonate. A small library of target compounds was prepared under optimized reaction conditions in moderate to good yields with high distereoselective and enantioselective properties. The newly generated chiral carbon center was of an (S)-configuration as determined by x-ray diffraction.

GRAPHICAL ABSTRACT

Keywords:

• Asymmetric synthesis
• benzofuran-derived β-amino esters
• diethyl bromomalonate
• domino reactions
• N-tert-butanesulfinamide

SUPPLEMENTAL MATERIAL

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