Internal Lewis Acid Assisted Benzoic Acid Catalysis

Abstract

Internal Lewis acid assisted benzoic acid derivatives are introduced as new low-molecular-weight single-hydrogen-bond donor catalysts for the activation of nitroalkenes. Selected 2-borylbenzoic acid derivatives gave good yields of products in the addition of indoles to nitroalkenes. Control experiments suggest that both the internal Lewis acid coordination and the carboxylic acid functionalities are critical to the optimal performance of these catalysts.

Key words

catalysis - addition reactions - alkene - boron - indoles

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