1634-74-8Relevant academic research and scientific papers
Porphyrin-Based Air-Stable Helical Radicals
Kato, Kenichi,Furukawa, Ko,Mori, Tadashi,Osuka, Atsuhiro
, p. 572 - 575 (2018)
Stable helical radicals are promising multi-functional molecules in light of intriguing magnetic and chiroptical properties. Attempts were made to extend diphenylmethyl-fused NiII porphyrin radical to helical system as the first air-stable orga
N-heterocyclic carbene–palladium complexes for Suzuki–Miyaura coupling reaction with benzyl chloride and aromatic boronic acid leading to diarylmethanes
Chen, Ming-Tsz,Wang, Wan-Rong,Li, Yi-Jun
, (2019/04/08)
A family of N-heterocyclic carbene–palladium(II)–N,N-dimethylbenzylamine complexes ((NHC)LPdCl2; L?=?N,N-dimethylbenzylamine) were synthesized as well as characterized using single-crystal X-ray diffraction and spectroscopic data. These complexes exhibited higher catalytic activities for the Suzuki reaction of benzyl chlorides to afford diarylmethanes under milder conditions than other efficient (NHC)LPdCl2 complexes. Using the optimum conditions, the expected coupling products were obtained in moderate to high yields. All reactions were carried out in air and all starting materials were used as supplied without purification.
Functional Ionic Liquids as Efficient and Recyclable Catalysts for the Methylation of Formaldehyde with Aromatics
Song, Heyuan,Jin, Fuxiang,Jin, Ronghua,Kang, Meirong,Li, Zhen,Chen, Jing
, p. 1264 - 1272 (2016/07/06)
Abstract: Methylation of formaldehyde with various aromatics under functional ionic liquids catalysis has been developed. Among the ionic liquids investigated, triphenyl-(4-sulfobutyl)-phosphonium triflate ([TTPBs][CF3SO3]) showed high activity and afforded excellent yields of diarylmethane derivatives. A mechanism for the catalytic performance of [TTPBs][CF3SO3] is proposed. Besides, the catalyst can simply be separated from the reaction mixture by centrifugation and be recycled ten times without noticeable loss of activity. Graphical Abstract: Diarylmethane derivatives were successfully synthesized from the methylation of formaldehyde with aromatics using efficient and recyclable functional ionic liquids as catalysts, excellent yields and selectivities were obtained under solvent free conditions. The catalyst was reused at least ten consecutive recycles without noticeable loss in its catalytic activity. Meanwhile, the usability of catalyst was explored.[Figure not available: see fulltext.]
Benzylation of arenes with benzyl ethers promoted by the in situ prepared superacid BF3-H2O
Li, Yu,Xiong, Yan,Li, Xueming,Ling, Xuege,Huang, Ruofeng,Zhang, Xiaohui,Yang, Jianchun
supporting information, p. 2976 - 2981 (2014/06/10)
An efficient and environmentally friendly benzylation of arenes with benzyl ethers as benzyl donors using BF3-Et2O to generate in situ the superacid BF3-H2O as an efficient promotor has been described. A wide variety of functional groups have been investigated and found to be compatible to give the desired diarylmethanes in yields of up to 99%. The crucial role of the moisture content in this transformation has been demonstrated by detailed investigations. This journal is the Partner Organisations 2014.
Facile one-pot palladium-catalyzed sequential coupling to diarylmethanes by using aryl methyl ketones as the methylene donors
Wang, Xing,Liu, Lian-Hua,Shi, Jin-Hua,Peng, Ji,Tu, Hai-Yang,Zhang, Ai-Dong
, p. 6870 - 6877 (2013/11/06)
A novel palladium-catalyzed coupling reaction of an aryl methyl ketone with two molecules of an aryl halide to yield symmetric diarylmethanes is described. In the facile one-pot reaction, the aryl methyl ketone acts as a formal methylene donor. The experimental facts, including TLC monitoring, speculated intermediates as the raw materials, analysis of the cesium benzoate coproduct by ex situ IR spectroscopy, and the cross-coupling reactions of two different aryl halides, indicate a mechanism involving a palladium-catalyzed sequential two-step coupling process, in which the presence of a trace amount of H 2O is indispensable. The reaction is applicable to a broad spectrum of substrates and delivers the products in good to excellent yields. Access to unsymmetrical diarylmethanes with this method is also explored and various factors are discussed. An aryl methyl ketone is used as the methylene donor to couple with two molecules of an aryl halide for the synthesis of various symmetric diarylmethanes under palladium catalysis. The mechanism involves a two-step coupling process in which the presence of a trace amount of H 2O is indispensable. The cross-coupling to unsymmetrical diarylmethanes with this method is also explored. Copyright
One-pot synthesis of symmetrical and unsymmetrical diarylmethanes via diborylmethane
Endo, Kohei,Ishioka, Takafumi,Ohkubo, Takahiro,Shibata, Takanori
, p. 7223 - 7231 (2012/10/29)
A one-pot synthesis of diarylmethanes from air-stable diborylmethane via the Suzuki-Miyaura cross-coupling reaction is described. The present approach realizes the synthesis of various symmetrical and unsymmetrical diarylmethanes in good to excellent yields.
Catalytic double C-Cl bond activation in CHlby iron(III) salts with grignard reagents
Qian, Xin,Kozak, Christopher M.
experimental part, p. 852 - 856 (2011/06/21)
Cross-coupling of Grignard reagents with dichloromethane is achieved using iron(III) catalysts. Aryl- and benzylmagnesium bromides show a range of activity toward double C-Cl bond activation resulting in the insertion of methylene fragments between two equivalents of the nucleophilic partner. Georg Thieme Verlag Stuttgart.
Synthesis and structural characterization of complexes derived from treatment of gallium trichloride with 3,5-diphenylpyrazole
Yu, Zhengkun,Korolev, Andrey V.,Heeg, Mary Jane,Winter, Charles H.
, p. 1117 - 1123 (2008/10/08)
The adduct GaCl3(Ph2pzH) (Ph2pzH, 3,5-diphenylpyrazole) was synthesized in 96% yield upon treatment of equimolar amounts of gallium trichloride with Ph2pzH in toluene at room temperature. The tetrachlorogallate
Palladium-Catalyzed Methylation of Aryl and Vinyl Halides by Stabilized Methylaluminum and Methylgallium Complexes
Blum, Jochanan,Gelman, Dmitri,Baidossi, Wael,Shakh, Eduard,Rosenfeld, Ayelet,Aizenshtat, Zeev,Wassermann, Birgit C.,Frick, Michael,Heymer, Bernd,Schutte, Stefan,Wernik, Sonja,Schumann, Herbert
, p. 8681 - 8686 (2007/10/03)
The intramolecularly stabilized mono- and dialkylaluminum complexes 1a, 2, 3, 4a, 5a, 5c, 6a, 6c, 7, 8, and 9 in the presence of palladium catalysts, cross-alkylate aryl, vinyl, and benzyl bromides and iodides under mild standard laboratory conditions. Aryl bromides with carbonyl substituents or benzylic halides are converted partially into dialkyl compounds. Under similar conditions, the analogous stabilized dimethylgallium complexes 1b, 4b, 5b, 6b, and 10 methylate aryl and vinyl bromides and iodides in a highly selective manner. Substituted bromobenzenes XC6H4Br, where X = CHO, COPh, CO2Et, CN, NO2, Cl, CH2Br, or CH=CHCOPh, are methylated by the organogallium reagents usually only at the aromatic ring halogen atom to give substituted toluenes as single products. The methylation rates were shown to depend on the nature of the chelating ligands, on the solvent, and on the type of palladium catalyst employed.
Acidity of Dibasic Acids I: the Second Acidity Constant of 9,10-Dihydroanthracene and its 9,10-Substituted Derivatives: Effect of Substituent and Counter Ion
Shapiro, Israel O.,Nir, Malka,Hoffman, Roy E.,Rabinovitz, Mordecai
, p. 1519 - 1524 (2007/10/02)
The second equilibrium ion pair acidity constants (pK2) of 9,10-dihydroanthracene, 9-phenyl-9,10-dihydroanthracene, 9,10-diphenyl-9,10-dihydroanthracene and 9-cyano-9,10-dihydroanthracene with sodium, potassium and rubidium have been determined in tetrahydrofuran (THF) at 25 deg C in the concentration range 10-5-10-2 mol dm-3.Equilibria were monitored by UV-VIS and 1H NMR spectroscopies and the spectra of the dimetallic and monometallic salts reported.The dimetallic salts of all the dibasic carbon acids studied behave as contact ion pairs in THF.The pK2 of 9,10-dihydroanthracene is insensitive to substituent effect but is strongly dependent on the cation.
