24892-81-7Relevant academic research and scientific papers
Photoinduced Hydroarylation and Cyclization of Alkenes with Luminescent Platinum(II) Complexes
Cheng, Hanchao,Lam, Tsz-Lung,Liu, Yungen,Tang, Zhou,Che, Chi-Ming
supporting information, p. 1383 - 1389 (2020/11/30)
Photoinduced hydroarylation of alkenes is an appealing synthetic strategy for arene functionalization. Herein, we demonstrated that aryl radicals generated from electron-deficient aryl chlorides/bromides could be trapped by an array of terminal/internal aryl alkenes in the presence of [Pt(O^N^C^N)] under visible-light (410 nm) irradiation, affording anti-Markovnikov hydroarylated compounds in up to 95 % yield. Besides, a protocol for [Pt(O^N^C^N)]-catalyzed intramolecular photocyclization of acrylanilides to give structurally diverse 3,4-dihydroquinolinones has been developed.
Synthesis and characterization of Pd(II) and Ru(II) complexes of tetradentate N,N,N,N-(Diphosphinomethyl)amine ligands: Catalytic properties in transfer hydrogenation and heck coupling reactions
Akkaya, Seda K??ker,Kele?, Mustafa,Uru?, Serhan
, (2020/07/13)
– Tetradentate N,N,N,N-(diphosphinomethyl)amine ligands and their Pd(II) and Ru(II) complexes were synthesized under a nitrogen atmosphere using Schlenk technique. The synthesized ligands and the complexes were characterized with 1H- and 31P-NMR, FT-IR, TG/DTA, and elemental analysis techniques. Pd(II) Complexes were used as catalysts in Heck coupling reactions and Ru(II) complexes were tried in transfer hydrogenation reactions of acetophenone derivatives. According to the results, L4-Pd(II) complex showed the best catalytic activity in the Heck coupling reaction of p-methylbromobenzene with o-chlorostyrene. It was confirmed that the reduction of bromo and chloroacetophenones in all catalysts the conversions were higher. The results showed that Ru(II) complexes as efficient catalysts and up to 99percent conversions was occurred with bromo and chloro acetophenones in K2CO3/isopropyl alcohol media at 80 °C.
Cu/Ni-Catalyzed Cyanomethylation of Alkenes with Acetonitrile for the Synthesis of β,γ-Unsaturated Nitriles
Jian, Hong,Shen, Zengming,Zhang, Saisai
, p. 6143 - 6150 (2020/05/22)
We have developed a protocol for the Cu/Ni-catalyzed cyanomethylation of alkenes with acetonitrile for the synthesis of β,γ-unsaturated nitriles. This is the first example of a direct coupling of the alkene sp2 C - H bond and the acetonitrile sp3 C - H bond for the preparation of β,γ-unsaturated nitriles. Acetonitrile, an inexpensive and stable solvent, is demonstrated to be a useful cyanomethyl source. The combination of copper and nickel catalysts resulted in a high reaction efficiency.
Bisoxazoline-pincer ligated cobalt-catalyzed hydrogenation of alkenes
Ritz, Mikhaila D.,Parsons, Astrid M.,Palermo, Philip N.,Jones, William D.
supporting information, (2020/02/13)
The efficient and atom economical hydrogenation of alkenes using a novel bisoxazoline ligated cobalt complex has been developed. The hydrogenation of a variety of alkenes containing electron neutral and electron-donating groups proceeds in high yield, whi
Synthesis of Trifluoromethylated Tetrasubstituted Allenes via Palladium-Catalyzed Carbene Transfer Reaction
Koenigs, Rene M.,Pei, Chao,Yang, Zhen
supporting information, p. 7300 - 7304 (2020/10/02)
Herein, we report on the palladium-catalyzed synthesis of trifluoromethylated, tetrasubstituted allenes from vinyl bromides and trifluoromethylated diazoalkanes in good to excellent yield. This reaction proceeds via oxidative addition of a Pd(0) complex w
Photocatalytic, Phosphoranyl Radical-Mediated N-O Cleavage of Strained Cycloketone Oximes
Xia, Peng-Ju,Ye, Zhi-Peng,Hu, Yuan-Zhuo,Song, Dan,Xiang, Hao-Yue,Chen, Xiao-Qing,Yang, Hua
supporting information, p. 2658 - 2662 (2019/04/25)
A photoinduced, phosphoranyl radical-mediated protocol for the direct N-O cleavage of strained cycloketone oximes via a polar/SET crossover process was developed for the first time. This visible-light-driven direct N-O activation mode for oxime offers beneficial features such as streamlined synthetic process and versatile photochemical reactivities. Consequently, the alkenes and α-trifluoromethyl alkenes with varied electronic and structural features acted as competent radical receptors in this protocol, enabling facile accesses to a range of elongated cyano and/or gem-difluoroalkene-bearing compounds.
Supported phosphotungstic acid catalyst on mesoporous carbon with bimodal pores: A superior catalyst for Friedel-Crafts alkenylation of aromatics with phenylacetylene
Zhao, Zhongkui,Wang, Xianhui
, p. 139 - 146 (2016/09/02)
Supported phosphotungstic acid (PTA) catalysts on diverse carriers containing the modified commercially available activated carbon (AC), classical mesoporous carbon via SBA-15 hard template method (CMK-3), and the mesoporous carbon with high surface area and bimodal pores through evaporation-induced tri-constituent co-assembly approach (MC) by using a facile wet impregnation method were employed as solid acid catalysts for Friedel-Crafts alkenylation of p-xylene with phenylacetylene. N2 adsorption–desorption, X-ray diffraction (XRD), and NH3 temperature-programmed desorption (NH3-TPD) characterization techniques were employed to reveal the structure-performance relationship. PTA/MC exhibits much superior catalytic performance to the previously reported PTA/AC, and even to PTA/CMK-3. The PTA/MC catalysts were optimized by varying the PTA loading, and the optimum PTA loading is 35%. The close to 100% of conversion towards phenylacetylene can be achieved in the presence of 2.67% of the 35% PTA/MC solid acid catalyst. It is also found that catalytic properties of the solid acids are strongly depended on acidic properties that affected by the textural properties of supports and PTA loading, as well as the accessibility of active sites affected by specific surface area and pore structure of catalyst. Moreover, the 35?wt.% PTA/MC catalyst has demonstrated outstanding catalytic performance for the Friedel-Crafts alkenylation of diverse aromatics to their corresponding α-arylstyrenes.
Traceless directing group mediated branched selective alkenylation of unbiased arenes
Agasti, Soumitra,Dey, Aniruddha,Maiti, Debabrata
supporting information, p. 12191 - 12194 (2016/10/21)
Owing to the synthetic importance of branched olefinated products, we report palladium catalyzed formation of branched olefins facilitated by a C-H activation based protocol. This involves selective insertion of olefins and subsequent decarboxylation using a completely unbiased benzene ring as the starting precursor. The significance of the protocol has been further highlighted by exhibition of functionality tolerance along with a late-stage modification of the branched olefinated products leading to the formation of other functionalized molecules.
Supported phosphotungstic acid catalyst on modified activated carbon for Friedel-Crafts alkenylation of diverse aromatics to their corresponding α-arylstyrenes
Zhao, Zhongkui,Wang, Xianhui
, p. 103 - 110 (2015/08/06)
Abstract The supported phosphotungstic acid catalysts on modified activated carbon (PTA/AC) prepared by a facile wet impregnation method were employed for Friedel-Crafts alkenylation of diverse aromatics with phenylacetylene to synthesize their corresponding α-arylstyrenes. Reaction results demonstrate that the fabricated PTA/AC catalyst with 30 wt.% PTA loading exhibits outstanding catalytic performance. The 100% conversion of phenylacetylene with 95.7% selectivity towards α-(2,5-dimethylphenyl) styrene can be achieved over the developed 30 wt.% PTA/AC catalyst under optimized reaction conditions, and no visible loss in catalytic performance can be observed after it suffers from several times recycling. The various characterization techniques including X-ray diffraction, N2 adsorption-desorption, Fourier transform infrared spectroscopy, and NH3 temperature-programmed desorption were employed to reveal the relationship between the catalysts nature and catalytic properties. Moreover, the results on the scope of aromatics for the Friedel-Crafts alkenylation illustrate that the developed PTA/AC alkenylation catalyst can be efficiently catalyze the diverse aromatics and even for the electron deficient chlorobenzene. The developed PTA/AC catalyst, using the modified low-cost and sustainable AC as support, may be a robust and promising candidate for highly-efficient and clean α-arylstyrenes production through Friedel-Crafts alkenylation of diverse aromatics including electron-donating and electron-withdrawing groups substituted benzene derivatives as well as heterocyclic and polypolycyclic arenes with phenylacetylene.
Wittig-olefination via an yttrium-coordinated betaine
Crimmin, Mark R.,White, Andrew J. P.
supporting information; experimental part, p. 1745 - 1747 (2012/03/09)
We report the synthesis of an yttrium phosphonium methylide complex and its reaction with benzophenone to form an excedingly rare hydrocarbon soluble metal-coordinated betaine. While this reaction models the C-C σ-bond formation step of the Wittig reaction under salt-conditions, addition of Ph 3PO to the betaine complex results in formation of 1,1-diphenylethene.
