784-04-3Relevant academic research and scientific papers
Electronic Asymmetry of an Annelated Pyridyl-Mesoionic Carbene Scaffold: Application in Pd(II)-Catalyzed Wacker-Type Oxidation of Olefins
Bera, Jitendra K.,Dutta, Indranil,Kunnikuruvan, Sooraj,Reshi, Noor U Din,Saha, Sayantani,Yadav, Suman
, p. 11385 - 11393 (2020/11/23)
The two donor modules of an annelated pyridyl-mesoionic carbene ligand (aPmic) have different σ- and π-bonding characteristics leading to its electronic asymmetry. A Pd(II) complex 1 featuring aPmic catalyzes the oxidation of a wide range of terminal olefins to the corresponding methyl ketones in good to excellent yields in acetonitrile. The catalytic reaction is proposed to proceed via syn-peroxypalladation and a subsequent rate-limiting 1,2-hydride shift, which is supported by kinetic studies. The electronic asymmetry of aPmic renders a well-defined coordination sphere at Pd. The favored arrangement of reactants on the metal center features an olefin trans to the pyridyl module and a tbutylperoxide trans to the carbene. This arrangement gains added stability by the π-delocalization paved by the compatible orbitals on Pd, the pyridyl module, and the olefin that is perpendicular to the Pd(aPmic) plane. The π-interactions are absent in an alternate arrangement wherein the olefin is trans to the carbene. Density functional theory studies reveal the matching orbital overlaps responsible for the preferred arrangement over the other. This work provides an orbital description for the electronic asymmetry of aPmic.
1,2-Diethoxyethane catalyzed oxidative cleavage of gem-disubstituted aromatic alkenes to ketones under minimal solvent conditions
Liu, Kai-Jian,Deng, Ji-Hui,Zeng, Tang-Yu,Chen, Xin-Jie,Huang, Ying,Cao, Zhong,Lin, Ying-Wu,He, Wei-Min
supporting information, p. 1868 - 1872 (2020/01/31)
Aerobic oxidation using pure dioxygen gas as the oxidant has attracted much attention, but its application in synthetic chemistry has been significantly hampered by the complexity of catalytic system and potential risk of high-energy dioxygen gas. By employing 1,2-diethoxyethane as a catalyst and ambient air as an oxidant, an efficient protocol for the construction of various aryl-alkyl and diaryl ketones through oxidative cleavage of gem-disubstituted aromatic alkenes under minimal solvent conditions has been achieved.
Catalyst-Free Photodriven Reduction of α-Haloketones with Hantzsch Ester
Lu, Zheng,Yang, Yong-Qing
, p. 508 - 515 (2019/01/10)
Catalyst-free dehalogenation of α-haloketones under visible light irradiation is studied. The reactions were carried out in common organic solvent. The outcomes of dechlorination are excellent in yields up to 92%, and it is also applicable to bromides, which give even higher yields. The reaction is tolerable to a broad spectrum of substrates, especially to aromatic ketones, including various aryl and hetaryl groups. There are two examples of aliphatic ketones presented in the paper, although their reactivities are not as high as that of the aromatic ketones.
Visible light promoted copper-catalyzed Markovnikov hydration of alkynes at room temperature
Niu, Teng-fei,Jiang, Ding-yun,Li, Si-yuan,Shu, Xing-ge,Li, Huan,Zhang, Ai-ling,Xu, Jia-yu,Ni, Bang-qing
supporting information, p. 1156 - 1159 (2017/03/02)
A new and efficient method for the hydration of alkynes to the corresponding ketones was successfully developed. The hydration process proceeds smoothly at room temperature with 1% mol of CuCl as catalyst under visible light irradiation. This protocol is applicable to various alkynes, including aromatic alkynes, polycyclic aromatic and heterocyclic aromatic excellent regioselectivity in good to excellent yields.
P -Selective (sp2)-C-H functionalization for an acylation/alkylation reaction using organic photoredox catalysis
Pandey, Ganesh,Tiwari, Sandip Kumar,Singh, Bhawana,Vanka, Kumar,Jain, Shailja
supporting information, p. 12337 - 12340 (2017/11/20)
p-Selective (sp2)-C-H functionalization of electron rich arenes has been achieved for acylation and alkylation reactions, respectively, with acyl/alkylselenides by organic photoredox catalysis involving an interesting mechanistic pathway.
Chemoselective Continuous Ru-Catalyzed Hydrogen-Transfer Oppenauer-Type Oxidation of Secondary Alcohols
Labes, Ricardo,Battilocchio, Claudio,Mateos, Carlos,Cumming, Graham R.,De Frutos, Oscar,Rincón, Juan A.,Binder, Kellie,Ley, Steven V.
supporting information, p. 1419 - 1422 (2017/09/23)
A continuous flow method for the selective oxidation of secondary alcohols is reported. The method is based on an Oppenauer-type ruthenium-catalyzed hydrogen-transfer process that uses acetone as both solvent and oxidant. The process utilizes a low loading (1 mol%) of the commercially available ruthenium catalyst [Ru(p-cymene)Cl2]2 and triethylamine as a base and can be successfully applied to a range of different substrates, with a good level of functional group tolerance.
Introverted Phosphorus-Au Cavitands for Catalytic Use
Schramm, Michael P.,Kanaura, Mao,Ito, Kouhei,Ide, Masataka,Iwasawa, Tetsuo
supporting information, p. 813 - 820 (2017/01/18)
A preparative synthesis of an inwardly directed phosphoramidite-Au complex is described and a description of some of its catalytic performance. The molecular structure was determined by crystallographic analysis, which disclosed that the phosphoramidite ligand points “out” and places the complexed Au “in”. We investigated its catalytic activities and found that the inwardly directed Au is surrounded by three inert walls that provide new opportunities for supramolecular catalysis and study of reactive intermediates.
The micro-flow field reactor Friedel-Crafts application of the catalyst in the reaction
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Paragraph 0056-0060, (2017/02/24)
The invention discloses an application of a micro-flow field reactor in Friedel-Crafts reaction. An immobilized microchannel reactor is filled with nano iron oxide particles for catalysis of Friedel-Crafts acylation reaction of aromatic hydrocarbon and acetyl chloride, wherein the nano iron oxide particles are prepared by the following methods: dissolving an iron-containing inorganic matter with distilled water, respectively and simultaneously pumping a water solution of inorganic alkali and a water solution of the iron-containing inorganic matter into the immobilized microchannel reaction device; standing for 30 seconds to 1 minute, reacting at a room temperature, and centrifuging the reaction product; and washing and drying sediments, and then sintering in a muffle furnace at 500 DEG C for 2 hours. The immobilized microchannel reactor is filled with the nano iron oxide particles prepared by the method for catalysis of Friedel-Crafts acylation reaction of the aromatic hydrocarbon and acetyl chloride.
Metal free visible light driven oxidation of alcohols to carbonyl derivatives using 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) as catalyst
Samanta, Suvendu,Biswas, Papu
, p. 84328 - 84333 (2015/10/28)
3,6-Di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) catalyzed oxidation of alcohols to the corresponding carbonyl compounds under visible light irradiation is described. This reaction occurs smoothly at room temperature and shows good tolerance of functional groups. It provides an alternative approach for the synthesis of alkyl and aryl aldehydes and ketones.
Direct catalytic cross-coupling of alkenyllithium compounds
Hornillos, Valentn,Giannerini, Massimo,Vila, Carlos,Faans-Mastral, Martn,Feringa, Ben L.
, p. 1394 - 1398 (2015/02/19)
A catalytic method for the direct cross-coupling of alkenyllithium reagents with aryl and alkenyl halides is described. The use of a catalyst comprising Pd2(dba)3/XPhos allows for the stereoselective preparation of a wide variety of substituted alkenes in high yields under mild conditions. In addition (1-ethoxyvinyl)lithium can be efficiently converted into substituted vinyl ethers which, after hydrolysis, give readily access to the corresponding methyl ketones in a one pot procedure.
