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Updated: Aug 13, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Study of the racemization observed in the amide bond forming reaction on silica gel
1Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
Abstract:
Racemization resulting from the coupling of N-(3,5-dinitrobenzoyl)-L-leucine and 3-aminopropyl silica gel with several amide-coupling reagents is further investigated in order to explain the much higher degree of racemization on silica gel, as compared with the similar reaction in solution. Based on experiments using different types of solid supports, limited pore access and surface microchemical environment are ruled out as the possible reason for the higher degree of racemization that occurred on silica gel. Steric hindrance of the solid support is thought to have caused the amino group to be more basic relative to its nucleophilicity, leading to a higher degree of racemization.
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