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2-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)benzoic acid has been identified as a new single hydrogen bond donor organic catalyst for the addition of indole to β-nitrostyrene. This catalyst offers enhanced reactivity over other benzoic acid derivatives lacking the boron substituent and it was reasoned this benefit results from the internal coordination the Lewis acid to the carboxylic acid functionality causing an increase in the acidity and improvement in catalyst function. Key features of 2-boryl benzoic acid catalysts making them particularly attractive include: their ease of preparation, shelf stability and convenience of use.