142-60-9Relevant articles and documents
Method for preparing organic carboxylic ester through combined catalysis of aryl bidentate phosphine ligand
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Paragraph 0038, (2020/05/29)
The invention discloses a method for preparing organic carboxylic ester by combined catalysis of an aryl bidentate phosphine ligand. The method comprises the following steps: under the action of a palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, carrying out a hydrogen esterification reaction on terminal olefin, carbon monoxide and alcohol so as to generate theorganic carboxylic ester with one more carbon than olefin. According to the invention, by adoption of the palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, good catalytic activity and selectivity for the hydrogen esterification reaction of the olefin are achieved, and olefin carbonylation to synthesize organic carboxylic ester can be efficiently catalyzed. Thearyl bidentate phosphine ligand has a rigid skeleton structure of a rigid ligand and the flexibility of a flexible ligand, so the aryl bidentate phosphine ligand has proper flexibility due to the characteristic that the aryl bidentate phosphine ligand is soft and rigid, and a most favorable coordination mode and a stable active structure in space are favorably formed. In addition, the aryl bidentate phosphine ligand has the advantages of high stability, simple and convenient synthesis method and the like; and a novel industrial technology is provided for production of organic carboxylate compounds.
Cathodic reductive couplings and hydrogenations of alkenes and alkynes catalyzed by the B12 model complex
Shimakoshi, Hisashi,Luo, Zhongli,Tomita, Kazuya,Hisaeda, Yoshio
, p. 71 - 77 (2017/05/08)
The reductive coupling and hydrogenation of alkenes were catalyzed by the B12 model complex, heptamethyl cobyrinate perchlorate (1), in the presence of acid during electrolysis at??0.7?V vs. Ag/AgCl in acetonitrile. Conjugated alkenes showed a good reactivity during electrolysis to form reduced products. The product distributions were dependent on the substituents at the C[dbnd]C bond of the alkenes. ESR spin-trapping experiments using 5,5-dimethylpyrroline N-oxide (DMPO) revealed that the cobalt-hydrogen complex (Co–H complex) should be formed during the electrolysis and it functioned as an intermediate for the alkene reduction. The electrolysis was also applied to an alkyne, such as phenylacetylene, to form 2,3-diphenylbutane (racemic and meso) and ethylbenzene via styrene as reductive coupling and hydrogenated products, respectively.
A powerful tool for acid catalyzed organic addition and substitution reactions
Turhanen, Petri A.,Veps?l?inen, Jouko J.
, p. 26218 - 26222 (2015/10/20)
A novel green chemistry tool for acid catalyzed reactions has been developed. The multipurpose tool is based on the ability of dry solid materials to donate protons (H+) to starting materials combined with the simultaneous use of a nucleophile (e.g. NaI). The methods enable the following reactions to be conducted at 20-50 °C: selective addition of iodine or alcohols to more substituted carbon in R2CCH2 systems (R ≠ H), esterification reactions, e.g. free fatty acids with methanol, and at higher temperatures, (60-100 °C): esterification of free fatty acids with hindered alcohols (isopropanol), addition of iodine to CC bonds, opening of oxygen(s) containing heterocyclic rings, selective substitution of primary OH groups to iodine in the presence of other functional groups or secondary alcohol groups, esterification of alcohols with nitriles (R-CN), transesterification of fatty acid triglycerides to biodiesel and selective derivatization of primary hydroxyl groups (-CH2OH) over secondary moieties of sugars without any protection. Most of the reactions were also performed by a re-used Dowex cation exchange resin.