Stereoselective Synthesis of Benzosultam-Fused Tetrahydroquinazolines via [4+2]-Cycloaddition of Cyclic N-Sulfonyl Ketimines with 2-Aminophenyl Enones

Abstract

A [4+2]-cycloaddition reaction between cyclic N-sulfonyl ketimines and 2-aminophenyl enones, catalyzed by K₂CO₃, has been developed. This method provides a straightforward and efficient approach for synthesizing a wide range of structurally complex and highly functionalized benzosultam-fused tetrahydroquinazolines in high yields, with excellent diastereoselectivities.

Key words

[4+2]-cycloaddition - benzosultams - 2-aminophenyl enones - cyclic N-sulfonyl ketimines - tetrahydroquinazolines

Publication History

Received: 08 February 2025

Accepted after revision: 26 March 2025

Accepted Manuscript online:
26 March 2025

Article published online:
24 April 2025

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