Primary Alkylboronic Acids as Highly Active Catalysts for the Dehydrative Amide Condensation of α-Hydroxycarboxylic Acids

Risa Yamashita, Akira Sakakura,* Kazuaki Ishihara* 
Org. Lett.2013, 15 (14), 3654–3657.  (Published online: 26 June  2013) 
DOI: 10.1021/ol401537f 

Primary alkylboronic acids such as methylboronic acid and butylboronic acid are highly active catalysts for the dehydrative amide condensation of α-hydroxycarboxylic acids.  The catalytic activities of these primary alkylboronic acids are much higher than those of the previously reported arylboronic acids.  The present method was easily applied to a large-scale synthesis, and 14 g of an amide was obtained in a single reaction.