34713-70-7Relevant academic research and scientific papers
Cleavage of immobilized disubstituted triazenes with electrophiles: Solid-phase synthesis of alkyl halides and esters
Pilot, Claudine,Dahmen, Stefan,Lauterwasser, Frank,Br?se, Stefan
, p. 9179 - 9181 (2001)
An efficient, selective cleavage of polymer-bound disubstituted triazenes with trimethylsilyl halides produces alkyl chlorides, bromides and iodides in good to excellent purities and yields. Similarly, alkyl esters are formed upon cleavage with carboxylic
Efficient oxidation of alcohols with tert-butyl hydroperoxide catalyzed by Mo(CO)6 supported on multiwall carbon nanotubes
Araghi, Mehdi,Ghorbani, Azam,Yeganeh, Faten Eshrati
, p. 109 - 113 (2013)
Efficient oxidation of alcohols with tert-butyl hydroperoxide catalyzed by Mo(CO)6 supported on multiwall carbon nanotubes modified with 4-aminopyridine is reported. The effect of various parameters such as catalyst amount, solvent and oxidant was studied. The catalyst, [Mo(CO) 5@APy-MWCNT], showed high activity not only in the oxidation of benzylic and linear alcohols but also in the oxidation of secondary alcohols. The catalyst can be reused several times without significant loss of its activity.
Direct dichlorovinylation of some carbonyl compounds by trichloroethylene under conditions of phase-transfer catalysis
Jończyk, Andrzej,Gierczak, Agnieszka H
, p. 6083 - 6087 (2000)
Reaction of ketones 1 and 3 with trichloroethylene (TRI) carried out in the presence of 50% aq. NaOH and TBAHS as a catalyst, in ethyl ether (phase-transfer catalysis, PTC) afford 1,2-dichlorovinylated ketones 2 and 4, respectively in good yields, usually as mixtures of Z and E isomers. PTC reaction of aldehydes 5 with TRI, carried out with DMSO instead of TBAHS, yields O-dichlorovinylated products 6, as mixtures of isomers in the case of 6a. These products are formed via C- or O-addition of ambident enolate anions to dichloroacetylene (generated from TRI by a base) and fast protonation of highly basic dichlorovinyl anions thus formed. (C) 2000 Elsevier Science Ltd.
Metal complexes with atropisomeric sulfur ligands in asymmetric hydroformylation: X-ray structure of [Rh2( μ-biphes) ( cod) 2] (H2biphes = 4,4′-biphenanthrene-3,3′-dithiol)
Ruiz, Nuria,Aaliti, Abdellatif,Fornies-Camer, Jorge,Ruiz, Aurora,Claver, Carmen,Cardin, Christine J.,Fabbri, Davide,Gladiali, Serafino
, p. 79 - 87 (1997)
The addition of the atropisomeric racemic sulfur compound 4,4′-biphenanthrene-3,3′-dithiol (H2biphes) to a dichloromethane solution of [{M( μ-OMe)(cod)}2] (M = Rh, Ir, cod = cycloocta-1,5 -diene) afforded the dithiolate-bridged compl
Rhodium complexes with a new chiral amino-phosphinite ligand and their behavior as pre-catalysts in the hydroformylation of styrene
Brancatelli,Drommi,Bruno,Faraone
, p. 215 - 219 (2010)
The new amino-phosphinite chiral ligand (Sa)-4-((S)-1-(diphenylphosphinooxy)-3-methylbutan-2-yl)-4,5- dihydro-3H-dinaphtho[2,1-c:1′,2′-e]azepine (1) has been synthesized and the corresponding more stable oxide has been characterized by X-ray an
Tandem catalysis with a bifunctional site-isolated Lewis acid-Bronsted base metal-organic framework, NH2-MIL-101(Al)
Srirambalaji, Renganathan,Hong, Soonsang,Natarajan, Ramalingam,Yoon, Minyoung,Hota, Raghunandan,Kim, Yonghwi,Ho Ko, Young,Kim, Kimoon
, p. 11650 - 11652 (2012)
A metal-organic framework (MOF), NH2-MIL-101(Al), which acts as a bifunctional, site-isolated Lewis acid-Bronsted base heterogeneous catalyst, catalyzes a tandem Meinwald rearrangement-Knoevenagel condensation reaction with remarkable substrate selectivity.
Azaphosphine ligand and preparation method and application thereof
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Paragraph 0044; 0045; 0048-0051, (2022/01/20)
The present invention belongs to the field of homogeneous catalyst ligand technology, specifically a kind of azadronium ligand and preparation method and application thereof. Azazepronium ligand disclosed in the present invention, the structure of which i
Synthesis of rac-ɑ-aryl propionaldehydes via branched-selective hydroformylation of terminal arylalkenes using water-soluble Rh-PNP catalyst
Gao, Peng,Ke, Miaolin,Ru, Tong,Liang, Guanfeng,Chen, Fen-Er
, p. 830 - 834 (2021/08/26)
This work detailed the preparation of a class of water-soluble PNP ligands that differed by the nature of the substitute on phenyl ring of ligands. These ligands were incorporated into water-soluble rhodium-PNP complex catalysts that were used to regioselective hydroformylation of a series of terminal arylalkenes, providing efficient access to rac-α-aryl propionaldehydes in good to excellent yield (up to 97%) and branched-regioselectivity (up to 40:1 b/l ratio). Furthermore, gram-scale and diverse synthetic transformation demonstrated synthetic application of this methodology for non-steroidal antiinflammatory drugs.
Chemo- And regioselective hydroformylation of alkenes with CO2/H2over a bifunctional catalyst
Hua, Kaimin,Liu, Xiaofang,Wei, Baiyin,Shao, Zilong,Deng, Yuchao,Zhong, Liangshu,Wang, Hui,Sun, Yuhan
supporting information, p. 8040 - 8046 (2021/11/01)
As is well known, CO2 is an attractive renewable C1 resource and H2 is a cheap and clean reductant. Combining CO2 and H2 to prepare building blocks for high-value-added products is an attractive yet challenging topic in green chemistry. A general and selective rhodium-catalyzed hydroformylation of alkenes using CO2/H2 as a syngas surrogate is described here. With this protocol, the desired aldehydes can be obtained in up to 97% yield with 93/7 regioselectivity under mild reaction conditions (25 bar and 80 °C). The key to success is the use of a bifunctional Rh/PTA catalyst (PTA: 1,3,5-triaza-7-phosphaadamantane), which facilitates both CO2 hydrogenation and hydroformylation. Notably, monodentate PTA exhibited better activity and regioselectivity than common bidentate ligands, which might be ascribed to its built-in basic site and tris-chelated mode. Mechanistic studies indicate that the transformation proceeds through cascade steps, involving free HCOOH production through CO2 hydrogenation, fast release of CO, and rhodium-catalyzed conventional hydroformylation. Moreover, the unconventional hydroformylation pathway, in which HCOOAc acts as a direct C1 source, has also been proved to be feasible with superior regioselectivity to that of the CO pathway.
Combined Theoretical and Experimental Studies Unravel Multiple Pathways to Convergent Asymmetric Hydrogenation of Enamides
Yang, Jianping,Massaro, Luca,Krajangsri, Suppachai,Singh, Thishana,Su, Hao,Silvi, Emanuele,Ponra, Sudipta,Eriksson, Lars,Ahlquist, M?rten S. G.,Andersson, Pher G.
, p. 21594 - 21603 (2021/12/27)
We present a highly efficient convergent asymmetric hydrogenation of E/Z mixtures of enamides catalyzed by N,P-iridium complexes supported by mechanistic studies. It was found that reduction of the olefinic isomers (E and Z geometries) produces chiral amides with the same absolute configuration (enantioconvergent hydrogenation). This allowed the hydrogenation of a wide range of E/Z mixtures of trisubstituted enamides with excellent enantioselectivity (up to 99% ee). A detailed mechanistic study using deuterium labeling and kinetic experiments revealed two different pathways for the observed enantioconvergence. For α-aryl enamides, fast isomerization of the double bond takes place, and the overall process results in kinetic resolution of the two isomers. For α-alkyl enamides, no double bond isomerization is detected, and competition experiments suggested that substrate chelation is responsible for the enantioconvergent stereochemical outcome. DFT calculations were performed to predict the correct absolute configuration of the products and strengthen the proposed mechanism of the iridium-catalyzed isomerization pathway.
