29267-10-5Relevant articles and documents
Diphenylamine-Terephthalaldehyde Resin p-Toluenesulfonate (DTRT) as an Efficient Catalyst for Tetrahydropyranylation, Deprotection of Tetrahydropyranyl and Silyl Ethers, Esterification, and Transesterification
Tanemura, Kiyoshi,Suzuki, Tsuneo
, p. 72 - 80 (2016/02/09)
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Efficient condensation of carboxylic acids with alcohols catalyzed by fluorous ammonium triflates
Mercs, László,Pozzi, Gianluca,Quici, Silvio
, p. 3053 - 3056 (2007/10/03)
The use of fluorous ammonium salts as metal-free catalysts for the direct condensation of equimolar amounts of carboxylic acids and aliphatic alcohols has been investigated. Esterification reactions were thus conveniently carried out under mild fluorous biphasic conditions, in the presence of 1 mol % of fluorous ammonium triflate and without recourse to any additional water removal technique. Good to excellent ester yields were obtained in the case of primary and secondary aliphatic alcohols. The fluorous salt was easily recovered by simple phase separation and reused at least three times without considerable loss of activity.
Bulky diarylammonium arenesulfonates as selective esterification catalysts
Ishihara, Kazuaki,Nakagawa, Shoko,Sakakura, Akira
, p. 4168 - 4169 (2007/10/03)
More environmentally benign alternatives to current chemical processes, especially large-scale, fundamental reactions such as ester condensations, are highly desirable for many reactions. Bulky diarylammonium pentafluorobenzenesulfonates and tosylates serve as extremely active dehydration catalysts for the ester condensation reaction of carboxylic acids with equimolar amounts of sterically demanding alcohols and acid-sensitive alcohols. Typically, the esterification reaction is performed in heptane by heating at 80 °C in the presence of 1 mol % of the catalyst without removing water. Esterification with primary alcohols proceeds without solvents even at room temperature. Furthermore, 4-(N-mesitylamino)polystyrene resin-bound pentafluorobenzenesulfonate can be recycled more than 10 times without activity loss. Copyright