898554-75-1Relevant academic research and scientific papers
Efficient Pd-Catalyzed C—H Oxidative Bromination of Arenes with Dimethyl Sulfoxide and Hydrobromic Acid?
Yuan, Yizhi,Liang, Yujie,Shi, Shihui,Liang, Yu-Feng,Jiao, Ning
supporting information, p. 1245 - 1251 (2020/07/27)
We have developed an efficient Pd-catalyzed directed C—H bromination protocol, in which dimethyl sulfoxide (DMSO) is employed as oxidant with hydrobromic acid aqueous solution (HBr(aq)) as bromide source. The DMSO/HBr(aq) system, which is novelly and efficiently utilized in transition-metal catalyzed C—H activation, illustrates its practicability by the operational simplicity, inexpensive and readily available starting materials, and high bromide-atom economy.
Scope of regioselective Suzuki reactions in the synthesis of arylpyridines and benzylpyridines and subsequent intramolecular cyclizations to azafluorenes and azafluorenones
Laha, Joydev K.,Patel, Ketul V.,Saima,Pandey, Surabhi,Solanke, Ganesh,Vashisht, Vanya
supporting information, p. 16069 - 16074 (2018/10/04)
The current investigation on regioselective Suzuki reactions of 2,3-dihalopyridines and 2-halo-3-halomethylpyridines yielded the unexplored synthesis of arylpyridines and benzylpyridines bearing synthetic handles for further functionalization. Indeed, the scope of intramolecular cyclizations of arylpyridines and benzylpyridines prepared in this study for the synthesis of azafluorenes and azafluorenones has been investigated.
Sodium halides as halogenating reagents: Rhodium(III)-catalyzed versatile and practical halogenation of aryl compounds
Zhang, Panpan,Hong, Liang,Li, Guofeng,Wang, Rui
supporting information, p. 345 - 349 (2015/02/19)
We report a concise, versatile and practical method for the ortho-chlorination, ortho-bromination and ortho -iodination of aryl compounds. The significant advantage of this transformation is the creation of the carbon-halogen bond by use of readily available and cheap halide salts as formal nucleoACHTUNGTRENUNGphilic halogenating reagents under mild reaction conditions.
Selective N -Chelation-directed C-H activation reactions catalyzed by pd(II) nanoparticles supported on multiwalled carbon nanotubes
Korwar, Sudha,Brinkley, Kendra,Siamaki, Ali R.,Gupton, B. Frank,Ellis, Keith C.
supporting information, p. A1782 - A1785 (2015/04/14)
N-Chelation-directed C-H activation reactions that utilize the Pd(II)/Pd(IV) catalytic cycle have been previously reported. To date, these reactions employ only homogeneous palladium catalysts. The first use of a solid-supported Pd(II) catalyst [Pd(II) nanoparticles on multiwalled carbon nanotubes, Pd(II)/MWCNT] to carry out N-chelation-directed C-H to C-O, C-Cl, and C-Br transformations is reported. The results presented demonstrate that the solid-supported Pd(II)/MWCNT catalyst can effectively catalyze C-H activation reactions using the Pd(II)/Pd(IV) catalytic cycle.
Metalation of a thiocatechol-functionalized Zr(IV)-based metal-organic framework for selective C-H functionalization
Fei, Honghan,Cohen, Seth M.
supporting information, p. 2191 - 2194 (2015/03/04)
The incorporation of 2,3-dimercaptoterephthalate (thiocatecholate, tcat) into a highly robust UiO-type metal-organic framework (MOF) has been achieved via postsynthetic exchange (PSE). The anionic, electron-donating thiocatecholato motif provides an excel
Indenopyridine-based compounds and organic light emitting diodes includiing the same
-
Paragraph 0322; 0352-0354, (2016/10/27)
Disclosed are indenopyridine-based compounds and organic light emitting diodes including the same. The disclosed organic light emitting diodes comprise: a first electrode; a second electrode facing the first electrode; an organic layer interposed between
Cu-mediated direct aryl C - H halogenation: A strategy to control mono- and di-selectivity
Du, Zhi-Jun,Gao, Lian-Xun,Lin, Ying-Jie,Han, Fu-She
, p. 123 - 126 (2014/01/23)
A protocol for the copper-mediated direct aryl C - H halogenation is presented. Highly selective mono- and di-halogenations are achieved by using acyl hypohalites, generated in situ from the readily available carboxylic acid and N-halosuccinimides (NXS; X=Br and Cl) as powerful halogenating reagents. The correct choice of carboxylic acid additives and solvents is essential for both high yield and selectivity. Consequently, the use of inexpensive Cu catalyst and the new strategy for the in situ generation of acyl hypohalite halogenating reagents from the readily affordable and easily-to-handle carboxylic acid and NXS (X=Br and Cl) offers advantages for practical application. Copyright
On the mechanism of palladium-catalyzed aromatic C-H oxidation
Powers, David C.,Xiao, Daphne Y.,Geibel, Matthias A. L.,Ritter, Tobias
supporting information; experimental part, p. 14530 - 14536 (2010/12/18)
The mechanism of Pd-catalyzed aromatic C-H oxidation chemistry continues to be vigorously discussed. Historically, Pd(II)/Pd(IV) catalysis cycles have been proposed. Herein, we present a detailed study of Pd(OAc)2-catalyzed aromatic C-H chlorination and propose dinuclear Pd(III) complexes as intermediates. We have identified a succinate-bridged dinuclear Pd(II) complex, which self-assembles during catalysis, as the catalyst resting state. In situ monitoring of catalysis has revealed that chlorination proceeds with turnover-limiting oxidation of a dinuclear resting state, and that acetate ions, liberated during the formation of the catalyst resting state, catalyze the bimetallic oxidation. Informed by reaction kinetics analysis, relevant dinuclear Pd(III) complexes have been prepared and observed to undergo selective C-Cl reductive elimination. Based on the combination of kinetic data obtained during catalysis and explicit structural information of relevant intermediates, we propose a Pd(II)2/Pd(III)2 catalysis cycle for Pd(OAc)2-catalyzed aromatic C-H chlorination.
Bimetallic palladium catalysis: Direct observation of Pd(III)-Pd(III) intermediates
Powers, David C.,Geibel, Matthias A. L.,Klein, Johannes E. M. N.,Ritter, Tobias
supporting information; experimental part, p. 17050 - 17051 (2010/03/25)
(Chemical Equation Presented) PhI(OAc)2 is a common oxidant for Pd-catalyzed C-H bond functionalizations. Mechanistic hypotheses since the 1960s have suggested a Pd(II)/Pd(IV) mechanism. Here we present evidence for the relevance of bimetallic Pd(III) complexes to catalysis. A bimetallic Pd(III) acetate was isolated and can afford product by bimetallic reductive elimination.
Chelating N-heterocyclic carbene alkoxide as a supporting ligand for PdII/IV C-H bond functionalization catalysis
Arnold, Polly L.,Sanford, Melanie S.,Pearson, Stephen M.
supporting information; experimental part, p. 13912 - 13913 (2009/12/25)
(Chemical Equation Presented) A PdIV complex that represents a viable catalytic intermediate in Pd-catalyzed C-H bond halogenation reactions has been isolated and structurally characterized. It contains the first examples of both a PdIV NHC bond and a PdIV alkoxide bond and serves as a precatalyst for C-H bond halogenation. As such, this represents a new class of tunable supporting ligand systems in PdIV catalysis.
