Bulky Diarylammonium Arenesulfonates as Selective Esterification Catalysts
Kazuaki Ishihara,* Shoko Nakagawa and Akira Sakakura
*Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan, Email: ishiharacc.nagoya-u.ac.jp
K. Ishihara, S. Nakagawa, A. Sakakura, J. Am. Chem. Soc., 2005, 127, 4168-4169.
DOI: 10.1021/ja050223v (free Supporting Information)
Bulky diarylammonium pentafluorobenzenesulfonates and tosylates serve as efficient dehydration catalysts for the ester condensation reaction of carboxylic acids with equimolar amounts of sterically demanding alcohols and acid-sensitive alcohols. Typically, the esterification is performed in heptane at 80°C in the presence of 1 mol % of the catalyst without removing water. A polymer-bound catalyst is described, which can be recycled more than 10 times without loss of activity.
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