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Updated: Jan 28, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
N-Heterocyclic Carbene-Catalyzed Decarboxylative Alkylation of Aldehydes
Takuya Ishii1, Yuki Kakeno1, Kazunori Nagao1
1Division of Pharmaceutical Sciences, Graduate School of Medical Sciences , Kanazawa University , Kakuma-machi, Kanazawa 920-1192 , Japan.
Abstract:
We found that N-heterocyclic carbene catalysis promoted the unprecedented decarboxylative coupling of aryl aldehydes and tertiary or secondary alkyl carboxylic acid-derived redox-active esters to produce aryl alkyl ketones. The mild and transition-metal-free reaction conditions are attractive features of this method. The power of this protocol was demonstrated by the functionalization of pharmaceutical drugs and natural product. A reaction pathway involving single electron transfer from an enolate form of Breslow intermediate to a redox ester followed by recombination of the resultant radical pair to form a carbon-carbon bond is proposed.
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