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Updated: Jul 10, 2025

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
[4+2]-Cycloaddition of 2-Aminophenyl Enones with Cyclic N-Sulfimines to Access Enantioenriched Ring-Fused Aminals
Yurim Kim1, Yoseop Kim1, Sung-Gon Kim1
1Department Department of Chemistry, Kyonggi University, Address 1154-42, Gwanggyosan-ro, Yeongtong-gu, Suwon, 16227, Republic of Korea.
Abstract:
Ring-fused aminal is an interesting structural skeleton in biologically active and pharmaceutically relevant compounds. A novel and efficient method for synthesizing benzosulfamidate-fused tetrahydroquinazolines is described. By employing the [4+2]-cycloaddition of 2-aminophenyl enones with cyclic N-sulfimines in the presence of DMAP as a base, the desired benzosulfamidate-fused tetrahydroquinazolines were obtained in good yields with high diastereoselectivities. Furthermore, an organocatalytic asymmetric [4+2]-cycloaddition was successfully achieved using a squaramide-based catalyst, enabling the enantioselective synthesis of chiral ring-fused tetrahydroquinazolines with high yields and enantio- as well as diastereoselectivities (up to 89 % yield, 94 % ee, and >30 : 1 dr).
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