2437-05-0Relevant articles and documents
Enantioselective Rauhut–Currier Reaction with β-Substituted Acrylamides Catalyzed by N-Heterocyclic Carbenes
Pitchumani, Venkatachalam,Breugst, Martin,Lupton, David W.
supporting information, p. 9413 - 9418 (2021/12/09)
β-Substituted acrylamides have low electrophilicity and are yet to be exploited in the enantioselective Rauhut–Currier reaction. By exploiting electron-withdrawing protection of the amide and moderate nucleophilicity N-heterocyclic carbenes, such substrates have been converted to enantioenriched quinolones. The reaction proceeds with complete diastereoselectivity, good yield, and modest enantioselectivity. Derivatizations are reported, as are computational studies, supporting decreased amide bond character with electron-withdrawing protection of the nitrogen.
Pd/Cu-Free Cobalt-Catalyzed Suzuki and Heck Using Green Bio-Magnetic Hybrid and DFT-Based Theoretical Study
Hajipour, Abdol R.,Khorsandi, Zahra,Ahmadi, Mehnoosh,Jouypazadeh, Hamidreza,Mohammadi, Bahareh,Farrokhpour, Hossein
, p. 2842 - 2850 (2021/02/01)
Abstract: Several highly efficient and magnetically recyclable cobalt catalytic systems were prepared using magnetic chitosan and some safe and available organic compounds (Co-ligand@MNPs/Ch). The structure of these nanocomposites was confirmed by various physicochemical techniques such as FT-IR, XRD, TGA, VSM, TEM, SEM, CHNS and ICP-OES. These nano composites exhibit remarkable catalytic efficiency for Suzuki and Heck cross-coupling reactions in mild and green reaction conditions. The facile accessibility of starting materials, possible performance in air and eco-friendly conditions are merits of our catalysts. In addition, to describe and go insight to role and effect of ligands present in these catalysts, electrostatic interactions, density functional theory (DFT) model in molecular method were employed. Graphic Abstract: [Figure not available: see fulltext.]
Sulphonic acid functionalized porphyrin anchored with a: Meso -substituted triazolium ionic liquid moiety: A heterogeneous photo-catalyst for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation
Bhansali, Karan,Raut, Subodh,Barange, Shital,Bhagat, Pundlik
, p. 19690 - 19712 (2020/12/04)
We report an easy process to synthesize sulphonic acid functionalized porphyrin, anchored with a meso-substituted triazolium ionic liquid moiety (SAFPTILM) for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation. The acid strength has been measured based on the Hammett indicator. The SAFPTILM photocatalyst comprising 18 π-conjugated electronic systems with the chromophore substituents in the meso-position can provide rapid electronic conducting channels during photocatalysis under the irradiation of visible light. It was found that SAFPTILM is an efficient photocatalyst for the Heck, Sonogashira, Buchwald, Ullmann/Fittig coupling and C-H activation of phenols with different aryl chlorides in the absence of a base/noble metal, using 5 W LED (yellow) light under ambient conditions. The photocatalyst with low band gap (1.55 eV) comprising conjugation, favors coupling reaction of unactivated aryl chlorides, by easy excitation of electrons and transfer to the conjugated benzimidazolium based phenylenediamine support delaying the recombination of photoinduced electron-hole pairs.
Palladium-melamine complex anchored on magnetic nanoparticles: A novel promoter for C-C cross coupling reaction
Bodaghifard, Mohammad Ali
, p. 57 - 64 (2019/03/06)
A palladium-melamine complex deposited on Fe3O4@SiO2 nanoparticles (MNPs-Mel-Pd) was considered as an effective catalyst for C-C cross-coupling (Mirozoki-Heck) reaction. Surface and magnetic properties of the prepared core-shell hybrid nanocatalyst was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, energy-dispersive X-ray, vibrating sample magnetometry, transmission and scanning electron microscopy techniques and ICP/OES analysis. It was found that the heterogeneous nanocatalyst could be recovered simply and reused numerous times without loss of its catalytic activity. The advantages of this new methodology are: isolation of highly pure products without chromatography techniques, reusability of the catalyst using a magnet, easy workup procedure and negligible leaching of palladium.
Synthetic method of indoline-2-ketone compound and application thereof
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Paragraph 0085-0088, (2018/12/13)
The invention discloses a synthetic method of an indoline-2-ketone compound and an application thereof. The synthetic method comprises the following steps: enabling a nitrobenzaldehyde compound, alkali and phosphorus ylide to react, and preparing a 2-nitr
Flexible, dicationic imidazolium salts for in situ application in palladium-catalysed Mizoroki–Heck coupling of acrylates under aerobic conditions
Milton, Marilyn Daisy,Garg, Parul
, p. 759 - 766 (2016/09/04)
The synthesis, characterization and in situ catalytic performance of new unsymmetric N,N′-disubstituted imidazolium-based dicationic salts in Mizoroki–Heck coupling of acrylates with aryl bromides under aerobic conditions are described. A series of flexible dicationic salts with varying steric and electronic properties were synthesized in good to excellent yields. All the salts were well characterized using spectroscopic techniques. X-ray diffraction analysis of two salts with the same dicationic backbone and different counter anions shows that the ligand adopts two different conformations which are influenced by the nature of the anion. Thus, the ligand is capable of changing its conformation according to the change in environment due to its flexible nature. All the synthesized imidazolium salts were found to be active in in situ palladium-catalysed Mizoroki–Heck coupling under aerobic conditions. Amongst the salts, the hydroxyl-functionalized imidazolium salt, incorporating the features of both bidentate chelating O,O ligand and carbene, shows the maximum catalytic activity. A variety of aryl and heteroaryl methyl and ethyl cinnamates were synthesized using these imidazolium salts as preligands. In addition, NMR studies confirm in situ generation of normal N-heterocyclic carbenes from the C-2 position of imidazol-2-ylidene ring. The mercury poisoning test was also performed to ascertain the nature of catalytically active palladium species. Aerobic conditions, low catalytic loading (0.5?mol%), shorter reaction times, broad functional group tolerance and good to excellent isolated yields are some of the significant features of the novel catalytic systems described here. Copyright
Synthesis, structural characterization and enzyme Inhibition studies on 5-(2-Nitrostyryl)-1,3,4-oxadiazole-2-thiol Derivatives
Abbasi, Muhammad Athar,Akhtar, Adnan,Aziz-Ur-Rehman,Nafeesa, Khadija,Siddiqui, Sabahat Zahra,Khan, Khalid Mohammed,Ashraf, Muhammad,Ejaz, Syeda Abida
, p. 2186 - 2190 (2014/03/21)
In the present work, S-substituted derivatives of 5-(2-nitrostyryl)-1,3,4- oxadiazole-2-thiol (4) were synthesized by successive conversions of 3-(2-nitrophenyl) acrylic acid (1) into its respective ester, hydrazide and 1,3,4-oxadiazole. Finally the targe
Concise total syntheses of Marinoquinolines A-C
Ni, Lijun,Li, Ziyuan,Wu, Fan,Xu, Jinyi,Wu, Xiaoming,Kong, Lingyi,Yao, Hequan
, p. 1271 - 1274 (2012/03/27)
The first concise total syntheses of pyrroloquinoline natural products, Marinoquinolines A-C, have been achieved in six linear steps from commercially available starting materials. The key steps were a reaction between (p-tolylsulfonyl)methylisocyanide (TosMIC) and α, β-unsaturated ester under basic condition to prepare the pyrrole moiety and Morgen-Walls reaction to construct quinoline ring.
Study on the Heck reaction promoted by carbene adduct of cyclopalladated ferrocenylimine and the related reaction mechanism
Ren, Gerui,Cui, Xiuling,Yang, Erbing,Yang, Fan,Wu, Yangjie
scheme or table, p. 4022 - 4028 (2010/07/05)
Carbene adduct of cyclopalladated ferrocenylimine has been successfully applied to Heck reaction of various aryl bromides with olefins. On the basis of kinetic studies, in situ 13C NMR spectra investigations and Hg poisoning experiments, it was proposed that the Heck reaction catalyzed by carbene adduct of cyclopalladated ferrocenylimine proceeded through a classical Pd(0)/Pd(II) cycle and such palladacycle was only a reservoir of the catalytically active Pd(0) species.
Microwave-assisted Cadogan reaction for the synthesis of 2-aryl-2H-indazoles, 2-aryl-1H-benzimidazoles, 2-carbonylindoles, carbazole, and phenazine
Creencia, Evelyn Cuevas,Kosaka, Masahiro,Muramatsu, Toshikatsu,Kobayashi, Masashi,Iizuka, Tomohiro,Horaguchi, Takaaki
experimental part, p. 1309 - 1317 (2010/03/23)
(Chemical Equation Presented) The Cadogan reaction, a widely accepted route for the synthesis of nitrogen containing heterocycles, is modified by using microwave radiation as the source of heat instead of the conventional heating by reflux in a nitrogen atmosphere for several hours. Appropriate starting materials were mixed with triethyl phosphite or triphenylphosphine and irradiated with microwaves for several minutes at a specific power to give the desired products. The indazoles were prepared by irradiating N-(2-nitrobenzylidene) anilines with triethyl phosphite at 200 W for 12-14 min to give 85-92% product yields. Irradiation of the mixture of N-benzylidene-2-nitroanilines and triphenylphosphine at 200 W for 3-5 min yielded 93-96% of the benzimidazoles. The carbonylindoles were obtained in 61-68% yields by irradiating 2-nitrochalcone or alkyl 2-nitrocinnamates and triphenylphosphine with microwaves at 80-200 W for 8-11 min. The mixture of 2-nitrobiphenyl and triphenylphosphine yielded 96% of carbazole when irradiated with microwaves at 200 W for 2 min while 75% of phenazine was obtained by irradiating the mixture of 2-nitrodiphenylamine and triphenylphosphine with microwaves at 200 W for 3.5 min. These results show that microwave-assisted Cadogan reactions gave better product yields at shorter reaction times.
