The Chemistry of Stable Carbenes. Part 2. Benzoin‐type condensations of formaldehyde catalyzed by stable carbenes

1996/02/07 by J. Henrique Teles, Johann‐Peter Melder, Klaus Ebel +8 · 5 citations
Chemistry · #N-Heterocyclic Carbenes in Organic and Inorganic Chemistry #Catalytic Cross-Coupling Reactions #Synthesis and Biological Evaluation

paper · doi:10.1002/hlca.19960790108

Abstract

Abstract Stable carbenes derived from thiazole, 1 H ‐imidazole, and 4 H ‐1,2,4‐triazole are efficient catalysts for benzointype condensations of formaldehyde. Catalysts derived from N ‐substituted thiazolium salts trimerize formaldehyde to dihydroxyacetone ( II ). Catalysts based on 1,4‐disubstituted 4 H ‐1,2,4‐triazol‐1‐ium salts give glycolaldehyde ( I ) as the main product and no II , whereas N,N ′‐disubstituted 1 H ‐imidazol‐3‐ium salts yield mixtures of both products. The isolation of several intermediates in the catalytic cycle provide a better insight into the reaction mechanism.

Citations

• Fully optimized contracted Gaussian basis sets for atoms Li to Kr

Cited by

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• 1-Butyl-3-methylimidazolium-Based Ionic Liquid in Biomass Fractionation-Green Solvent or Active Reagent Toward Lignin Compounds? [europepmc]
• CO-to-sugars conversion from one-pot two-step electro-organocatalytic process. [europepmc]
• Formaldehyde and its surrogates as a C1 platform for defossilised modern societies. [europepmc]

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