4-Fluoro and 4-Hydroxy Pyrrolidine-thioxotetrahydropyrimidinones: Organocatalysts for Green Asymmetric Transformations in Brine
作者:Nikolaos Kaplaneris、Giorgos Koutoulogenis、Marianna Raftopoulou、Christoforos G. Kokotos
DOI:10.1021/acs.joc.5b00283
日期:2015.6.5
The synthesis of both trans- and cis-diastereomers of pyrrolidinine-thioxotetrahydropyrimidinone bearing either a fluorine or a hydroxyl group was accomplished. The new compounds were tested for their catalytic properties in a variety of asymmetric organic transformations and compared with the first generation catalyst. It was found that the new catalysts could efficiently catalyze the reactions in
A hydrate salt-promoted reductive coupling reaction of nitrodienes with unactivated alkenes
作者:Mengmeng Zhang、Liming Yang、Chao Tian、Meng Zhou、Guanghui An、Guangming Li
DOI:10.1039/c9ob00136k
日期:——
Transition metal-catalyzed reductive coupling has emerged as a powerful method for the construction of C–C bonds. Herein, a crystalline hydrate, Na2HPO4·7H2O, has been disclosed as an effective promoter for the reductive coupling of nitrodienes with unactivated alkenes to afford diverse dienes with various functionalities in an open-flask manner. The mechanism study has revealed that Na2HPO4·7H2O accelerates
Use of a Traceless Activating and Directing Group for the Construction of Trifluoromethylpyrazoles: One-Pot Transformation of Nitroolefins and Trifluorodiazoethane
作者:Zhen Chen、Yan Zheng、Jun-An Ma
DOI:10.1002/anie.201700955
日期:2017.4.10
We disclose an efficient one‐pot transformation of trifluorodiazoethane and higher perfluorinated homologues with various nitroolefins. This method takes advantage of the nitro group as a traceless activating and directing group (TADG) that is released in the aromatization step to produce 4‐substituted 3‐perfluoroalkyl pyrazoles with complete regioselectivity. The potential of this method is further