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11.
A. L. Rusanov M. L. Keshtov N. M. Belomoina A. K. Mikitaev G. B. Sarkisyan S. V. Keshtova 《Russian Chemical Bulletin》1997,46(4):777-779
Bis (p-fluorophenylethynyl) derivatives were obtained by the reaction of bisbromoaromatic compounds withp-fluorophenylacetylene in the presence of a Pd catalyst. Subsequent oxidation of these products using an I2-DMSO system led to new bis(p-fluorophenylglyoxaly)ketones, α-diketones, and heterocyclic compounds.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 810–812, April, 1997. 相似文献
12.
A general synthetic route for the Pd-catalyzed cross-coupling of an arylzinc reagent with arylvinyl iodides (Negishi cross-coupling) has been developed. The system permits efficient and selective preparation of E-stilbenes and their analogues. It also functions effectively at low levels of catalyst loading without the need for an additional ligand and tolerates a wide range of functional groups including heteroaromatic substrates. A systematic study of various parameters was performed and correlated with catalyst-substrate activity. 相似文献
13.
N. A. Bumagin 《Russian Chemical Bulletin》1996,45(9):2031-2050
The results of the investigation of the cross-coupling of organometallic compounds and terminal acetylenes with organic halides catalyzed by transition metal complexes are generalized and analyzed. The influence of different factors on the rate and selectivity of catalytic cross-coupling is discussed. A detailed mechanism of the cross-coupling of Grignard reagents with organic halides is suggested. The cross-coupling reaction involving organotin compounds proceeds under very mild conditions in the presence of a ligand-free Pd catalyst. Examples of using catalytic cross-coupling of organic halides with organomagnesium, organozinc, and organotin compounds are presented.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2148–2167, September, 1996. 相似文献
14.
Aik Sian Tan Jaymeer Singh Nurul Syafiqah Rezali Musthahimah Muhamad Nik Nur Syazni Nik Mohamed Kamal Yvan Six Mohamad Nurul Azmi 《Molecules (Basel, Switzerland)》2022,27(17)
The Heck cross-coupling reaction is a well-established chemical tool for the synthesis of unsaturated compounds by formation of a new C-C bond. In this study, 1,3-diarylpropene derivatives, designed as structural analogues of stilbenoids and dihydrostilbenoids, were synthesised by the palladium-catalysed reactions of 2-amidoiodobenzene derivatives with either estragole or eugenol. The products were obtained with high (E) stereoselectivity but as two regioisomers. The ratios of isomers were found to be dependent on the nature of the allylbenzene partner and were rationalised by electronic effects exercising a determining influence in the β-hydride elimination step. In addition, the cytotoxic effects of all the Heck reaction products were evaluated against MCF-7 and MDA-MB-231 human breast cancer cells, with unpromising results. Among all, compound 7d exhibited weak cytotoxic activity towards MCF-7 cell lines with IC50 values of 47.92 µM in comparison with tamoxifen and was considered to have general toxicity (SI value < 2). 相似文献
15.
Ramil F. Fatykhov Igor A. Khalymbadzha Ainur D. Sharapov Anastasia P. Potapova Nataliya N. Mochulskaya Anton N. Tsmokalyuk Alexandra V. Ivoilova Polina N. Mozharovskaia Sougata Santra Oleg N. Chupakhin 《Molecules (Basel, Switzerland)》2022,27(20)
A different type of MnO2-induced oxidative cyclization of dihydrotriazines has been developed. These dihydrotriazines are considered as a “formal” Schiff’s base. This method provided easy access to naphthofuro-fused triazine via the C-C/C-O oxidative coupling reaction. The reaction sequence comprised the nucleophilic addition of 2-naphthol or phenol to 1,2,4-triazine, followed by oxidative cyclization. The scope and limitations of this novel coupling reaction have been investigated. Further application of the synthesized compound has been demonstrated by synthesizing carbazole-substituted benzofuro-fused triazines. The scalability of the reaction was demonstrated at a 40 mmol load. The mechanistic study strongly suggests that this reaction proceeds through the formation of an O-coordinated manganese complex. 相似文献
16.
Nitrogen-containing heterocycles represent the majority of FDA-approved small-molecule pharmaceuticals. Herein, we describe a synthetic method to produce saturated N-heterocyclic drug scaffolds with an internal alkyne for elaboration. The treatment of N,N-dimethylhydrazinoalkenes with Et2Zn, followed by a Cu(I)-catalyzed cross-coupling with 1-bromoalkynes, results in piperidines and pyrrolidines with a good yield. Five examples are reported and a proposed mechanism for the Cu(I)-catalyzed cross-coupling is presented. 相似文献
17.
Laccases are multicopper oxidases that have shown a great potential in various biotechnological and green chemistry processes mainly due to their high relative non-specific oxidation of phenols, arylamines and some inorganic metals, and their high redox potentials that can span from 500 to 800 mV vs. SHE. Other advantages of laccases include the use of readily available oxygen as a second substrate, the formation of water as a side-product and no requirement for cofactors. Importantly, addition of low-molecular-weight redox mediators that act as electron shuttles, promoting the oxidation of complex bulky substrates and/or of higher redox potential than the enzymes themselves, can further expand their substrate scope, in the so-called laccase-mediated systems (LMS). Laccase bioprocesses can be designed for efficiency at both acidic and basic conditions since it is known that fungal and bacterial laccases exhibit distinct optimal pH values for the similar phenolic and aromatic amines. This review covers studies on the synthesis of five- and six-membered ring heterocyclic cores, such as benzimidazoles, benzofurans, benzothiazoles, quinazoline and quinazolinone, phenazine, phenoxazine, phenoxazinone and phenothiazine derivatives. The enzymes used and the reaction protocols are briefly outlined, and the mechanistic pathways described. 相似文献
18.
A combinatorial nickel-catalyzed monofluoroalkylation of aryl bromides with the industrial raw regent ethyl chlorofluoroacetate has been developed. The two key factors to successful conversion are the combination of nickel with readily available nitrogen and phosphine ligands and the using of a mixture of different solvents. Mechanistic investigations indicated a new zinc regent might generated in situ and be involved in the reaction process. 相似文献
19.
Dr. Tao Shu Prof. Janine Cossy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(43):11021-11029
This review highlights the recent achievements of iron- and cobalt-catalyzed enantioselective cross-couplings of halide derivatives with organometallic reagents for the construction of C-C bonds. Synthetic applications of enantioselective cross-couplings to natural products and biologically active compounds are also covered showing the power of these cross-couplings in organic synthesis. 相似文献
20.
Shang Wu Hongheng Yu Qinzheng Hu Quanlu Yang Shouwang Xu Tian Liu 《Tetrahedron letters》2017,58(51):4763-4765
A silver-catalyzed decarboxylative cross-coupling of α-keto acids with alkenes is reported. The method, with a wide range of substrate tolerance and mild operational conditions, can produce various chalcone derivatives in moderate to high yields from easily available starting materials. 相似文献