50623-57-9Relevant articles and documents
Robust acidic pseudo-ionic liquid catalyst with self-separation ability for esterification and acetalization
Shi, Yingxia,Liang, Xuezheng
, p. 1413 - 1421 (2019/05/04)
The novel acidic pseudo-ionic liquid catalyst with self-separation ability has been synthesized through the quaternization of triphenylphosphine and the acidification with silicotungstic acid. The pseudo-IL showed high activities for the esterification with average conversions over 90%. The pseudo-IL showed even higher activities for acetalization than traditional sulfuric acid. The homogeneous catalytic process benefited the mass transfer efficiency. The pseudo-IL separated from the reaction mixture automatically after reactions, which was superior to other IL catalysts. The high catalytic activities, easy reusability and high stability were the key properties of the novel catalyst, which hold great potential for green chemical processes.
Synthesis of carboxylic acid esters in the presence of micro- and mesoporous aluminosilicates
Grigor'Eva,Suleimanova,Agliullin,Kutepov
, p. 773 - 779 (2015/01/30)
The catalytic properties of zeolites HY, HBeta, and HZSM-12 and of mesoporous amorphous aluminosilicate in liquid-phase esterification of aliphatic (monobasic C1-C18, dibasic C6, C10) and aromatic (benzoic, trimellitic, phthalic) carboxylic acids with butanol were studied. Zeolite HBeta appeared to be the most active catalyst. Procedures were developed for preparing esters in the presence of zeolitic catalyst HBeta, ensuring 100% selectivity of ester formation at 90-98% conversion of the acid.
Cobalt-catalyzed reductive coupling of saturated alkyl halides with activated alkenes
Shukla, Paritosh,Hsu, Yun-Chu,Cheng, Chien-Hong
, p. 655 - 658 (2007/10/03)
An efficient cobalt-catalyzed reductive coupling reaction of alkyl halides with electron-withdrawing alkenes (CH2=CR1EWG, EWG = electron-withdrawing group) in the presence of water and zinc powder in acetonitrile to give the corresponding Michael-type addition product (RCH 2CR1EWG) was described. The methodology is versatile such that unactivated primary, secondary, and tertiary alkyl bromides and iodides and various conjugated alkenes including acrylates, acrylonitrile, methyl vinyl ketone, and vinyl sulfone all successfully participate in this coupling reaction. For the alkyl halides used in the reaction, the iodides generally gave heller yields compared to those of the corresponding bromides. It is a unique method employing CoI2dppe, zinc, and alkyl halides, affording conjugate addition products in high yields. Mechanistically, the reaction appears to follow an oxidative addition driven route rather than the previously reported radical route.