N-Butyl-2,4-dinitro-anilinium p-toluenesulfonate (1) was found to be a very active esterification catalyst that promotes condensation of equal mole amount of carboxylic acids and alcohols under mild conditions. This catalyst is also highlyselective towards carboxylic acid and alcohol substrates at ambient temperature.
发现 N -Butyl-2,4-dinitro-anilinium p-甲苯磺酸盐( 1 ) 是一种非常活跃的酯化催化剂,可在温和条件下促进等摩尔量的羧酸和醇的缩合。该催化剂在环境温度下对羧酸和醇底物也具有高度选择性。
Bulky diarylammonium arenesulfonates as mild and extremely active dehydrative ester condensation catalysts
作者:Akira Sakakura、Shoko Nakagawa、Kazuaki Ishihara
DOI:10.1016/j.tet.2005.09.059
日期:2006.1
especially large-scale, fundamental reactions like estercondensations, are highly desirable for many reactions. Bulky diarylammonium pentafluorobenzenesulfonates and tosylates serve as extremely active dehydration catalysts for the estercondensation reaction of carboxylicacids with equimolaramounts of sterically demanding alcohols and acid-sensitive alcohols. Typically, the esterification reaction is performed
LUBRICATING OIL FOR REFRIGERATOR, HYDRAULIC FLUID COMPOSITION FOR REFRIGERATOR AND METHOD FOR LUBRICATION OF REFRIGERATOR
申请人:NEW JAPAN CHEMICAL CO.,LTD.
公开号:EP1225213A1
公开(公告)日:2002-07-24
The invention provides a lubricating oil for refrigerators, comprising (a) at least one ester represented by the formula (1)
wherein R1 is C1 to C18 straight-chain alkyl or C3 to C18 branched-chain alkyl; R2 is H, C1 to C18 straight-chain alkyl or C3 to C18 branched-chain alkyl; with the poviso that the total number of carbons contained in the alkyls represented by R1 and R2 is 2 to 18 and that when R2 is H, R1 is branched-chain alkyl; and R3 is C1 to C20 straight-chain alkyl, C3 to C20 branched-chain alkyl or C3 to C10 cycloalkyl, optionally in combination with (b) at least one member selected from the group consisting of fatty acid polyol esters, phthalic acid esters, alicyclic dicarboxylic acid esters, polyvinyl ethers, hydrocarbon oils and polyalkylene glycols; as well as a method for lubricating a refrigerator using such a lubricating oil, and a working fluid composition for refrigerators comprising (I) component (a) or components (a) and (b) and (II) a refrigerant.
Esterification Catalysis by Pyridinium <i>p</i>-Toluenesulfonate Revisited—Modification with a Lipid Chain for Improved Activities and Selectivities
作者:Wei Wang、Huimin Liu、Shaoyi Xu、Yong Gao
DOI:10.1080/00397911.2012.749990
日期:2013.11.2
The lipid analogs of pyridinium p-toluenesulfonate (PPTS) were examined for catalysis of the condensation of an equimolar mixture of carboxylic acids and alcohols under mild conditions without removal of water. Although PPTS is a poor catalyst, the introduction of a lipid chain and nitro group significantly improved the activity of PPTS and led to selectivity at suppressing the elimination side reactions of alcohols. 2-Oleamido-5-nitro-pyridinium p-toluenesulfonate (6) is a lead catalyst that promoted various esterification reactions with yields up to 99%. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) for the following free supplemental resource: Full experimental and spectral details.]