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Updated: May 29, 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
Asymmetric multi-component trifunctionalization reactions with α-Halo Rh-carbenes
Xiaoyan Yang1, Xiaoyu Zhou2, Wenhao Hu3
1State Key Laboratory of Anti-Infective Drug Discovery and Development, Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China.
Abstract:
Multi-component multi-functionalization reactions involving active intermediates are powerful tools for rapidly generating a wide array of compounds. Metal carbynoids, with their distinct reactivity, hold great promise for developing synthetic methodologies. However, their application in catalytic transfer reactions has been hindered by the limited availability of suitable precursors. In this study, we investigate the catalytic potential of α-halo Rh-carbenes, leveraging the concept of metal carbynoids in multi-functionalization reactions. Through a chiral phosphoric acid-catalyzed asymmetric trifunctionalization, we have developed a method for synthesizing a variety of chiral α-cyclic ketal β-amino esters with high yields and excellent enantioselectivity. Our extensive experimental and computational studies reveal that α-halo Rh-carbenes exhibit carbynoid properties, which facilitate the transformation into functionalized Fischer-type Rh-carbenes through the decomposition of the C-halo bond.
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