19842-76-3Relevant articles and documents
Synthetic method of transfluthrin intermediate
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Paragraph 0047; 0053-0054; 0057; 0063-0064; 0067; ..., (2021/08/25)
The invention discloses a synthetic method of a transfluthrin intermediate, and belongs to the technical field of chemical synthesis, the synthetic method is characterized by comprising the following steps: (1) taking 2, 3, 5, 6-tetrafluorobenzene as a raw material, and reacting with carbon tetrachloride to obtain 2, 3, 5, 6-tetrafluorotrichloromethyl benzene; (2) under the action of a composite catalyst, carrying out catalytic hydrolysis on the 2, 3, 5, 6-tetrafluorotrichloromethyl benzene to obtain 2, 3, 5, 6-tetrafluorobenzoyl chloride; (3) under the action of a catalyst, the 2, 3, 5, 6-tetrafluorobenzoyl chloride and hydrogen are subjected to a Rosenmonde reduction reaction, and 2, 3, 5, 6-tetrafluorobenzaldehyde is obtained; (4) carrying out catalytic hydrogenation reaction on the 2, 3, 5, 6-tetrafluorobenzaldehyde and hydrogen to obtain 2, 3, 5, 6-tetrafluorobenzyl alcohol; the method has the advantages of simple steps, high yield of each step and simple reaction; the reaction conditions of each step are mild, and the method has the advantages of low cost, high yield and easily available reaction conditions.
π-π Interaction assisted hydrodefluorination of perfluoroarenes by gold hydride: A case of synergistic effect on C-F bond activation
Lv, Hongbin,Zhan, Jin-Hui,Cai, Yuan-Bo,Yu, Yi,Wang, Bingwu,Zhang, Jun-Long
supporting information, p. 16216 - 16227,12 (2020/09/09)
Synergistic effect is prevalent in natural metalloenzymes in activating small molecules, and the success has inspired the development of artificial catalysts capable of unprecedented organic transformations. In this work, we found that the attractive π-π interaction between organic additives (as electron-donors) and the perfluorinated arenes (as electron acceptors) is effective in gold hydride catalyzed activation of C-F bonds, specifically hydrodefluorination (HDF) of perfluoroarenes catalyzed by the Sadighi's gold hydrides [(NHC)AuH] (NHC = N-heterocyclic carbene). Although a weak interaction between [(NHC)AuH] and perfluoroarenes was observed from 1H NMR and UV-vis spectroscopies, low reactivity of [(NHC)AuH] toward HDF was found. In contrast, in the presence of p-N,N-dimethylaminopyridine (DMAP), the HDF of perfluoroarenes with silanes can be efficiently catalyzed by [(NHC)AuH], resulting in mainly the para-hydrodefluorinated products with up to 90% yield and 9 turnovers. The yield of the reaction increases with the more electron-withdrawing groups and degree of fluorination on the arenes, and the HDF reaction also tolerates different function groups (such as formyl, alkynyl, ketone, ester, and carboxylate groups), without reduction or hydrogenation of these function groups. To reveal the role of DMAP in the reactions, the possible π-π interaction between DMAP and perfluoroarenes was suggested by UV-vis spectral titrations, 1H NMR spectroscopic studies, and DFT calculations. Moreover, 1H and 19F-NMR studies show that this π-π interaction promotes hydrogen transfer from [(NHC)AuH] to pyridyl N atom, resulting in C-F bond cleavage. The interpretation of π-π interaction assisted C-F activation is supported by the reduced activation barriers in the presence of DMAP (31.6 kcal/mol) than that in the absence of DMAP (40.8 kcal/mol) for this reaction. An analysis of the charge distribution and transition state geometries indicate that this HDF process is controlled by the π-π interaction between DMAP and perfluoroarenes, accompanied with the changes of partial atomic charges.
Process for producing tetrafluorobenzenemethanols
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, (2008/06/13)
The present invention relates to a process by a series of reactions using tetrafluorocyanobenzens as material for producing tetrafluorobenzenemethanols, tetrafluorobenzenecarbaldehyde dialkylacetals and tetrafluorobenzenecarbaldehydes in a high purity and a high yield which are useful as intermediates in the production of cyclopropanecarboxylic acid esters having insecticidal action, and also relates to a novel tetrafluorobenzenecarbaldehyde dimethylacetal.