17607-28-2Relevant articles and documents
DEVICE AND METHOD FOR EVALUATING ORGANIC MATERIAL FOR ORGANIC SOLAR CELL
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Paragraph 0082; 0083; 0084; 0085; 0086, (2014/08/07)
Provided are a novel 1,2-bis(dialkylphosphino)-4,5-(methylenedioxy)benzene derivative that forms a metal complex having particularly high asymmetry induction capacity and catalytic activity on β-dehydroamino acids, a method for manufacturing the same, a metal complex having this 1,2-bis(dialkylphosphino)-4,5-(methylenedioxy)benzene derivative as a ligand, and an asymmetric hydrogenation method using this metal complex. A 1,2-bis(dialkylphosphino)-4,5-(methylenedioxy)benzene derivative represented by general formula (1). (In the formula, R1 and R2 represent an alkyl group having 1-10 carbon atoms, and R1 and R2 have different numbers of carbon atoms.)
Rigid P-chiral phosphine ligands with tert -butylmethylphosphino groups for rhodium-catalyzed asymmetric hydrogenation of functionalized alkenes
Imamoto, Tsuneo,Tamura, Ken,Zhang, Zhenfeng,Horiuchi, Yumi,Sugiya, Masashi,Yoshida, Kazuhiro,Yanagisawa, Akira,Gridnev, Ilya D.
supporting information; experimental part, p. 1754 - 1769 (2012/03/11)
Both enantiomers of 2,3-bis(tert-butylmethylphosphino)quinoxaline (QuinoxP*), 1,2-bis(tert-butylmethylphosphino)benzene (BenzP*), and 1,2-bis(tert-butylmethylphosphino)-4,5-(methylenedioxy)benzene (DioxyBenzP*) were prepared in short steps from enantiopure (S)- and (R)-tert-butylmethylphosphine-boranes as the key intermediates. All of these ligands were crystalline solids and were not readily oxidized on exposure to air. Their rhodium complexes exhibited excellent enantioselectivities and high catalytic activities in the asymmetric hydrogenation of functionalized alkenes, such as dehydroamino acid derivatives and enamides. The practical utility of these catalysts was demonstrated by the efficient preparation of several chiral pharmaceutical ingredients having an amino acid or a secondary amine component. A rhodium complex of the structurally simple ligand BenzP* was used for the mechanistic study of asymmetric hydrogenation. Low-temperature NMR studies together with DFT calculations using methyl α-acetamidocinnamate as the standard model substrate revealed new aspects of the reaction pathways and the enantioselection mechanism.
Enantiopure 1,2-Bis(tert-butylmethylphosphino)benzene as a highly efficient ligand in rhodium-catalyzed asymmetric hydrogenation
Tamura, Ken,Sugiya, Masashi,Yoshida, Kazuhiro,Yanagisawa, Akira,Imamoto, Tsuneo
supporting information; experimental part, p. 4400 - 4403 (2010/12/25)
Figure Presented. An electron-rich P-stereogenic bisphosphine ligand named "BenzP" was conveniently prepared from o-dibromobenzene and enantiopure tert-butylmethylphosphine-borane. Its rhodium complex exhibited excellent enantioselectivities of up to 99.9% and high catalytic activity of up to 10000 h-1 TOF in asymmetric hydrogenations of various functionalized alkenes.