Asymmetric hydrogenation of prochiral carboxylic acids and functionalized carbonyl compounds catalysed by ruthenium(II)-binap complexes with aryl nitriles (binap = (R)- or (S)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl)
Complexes RuCl2(ArCN)2(binap), II (binap = (R)- or (S)-2,2′-bis(diphenylphosphino)- 1,1′-binaphthyl; ArCN = benzonitrile, a; 2-furancarbonitrile, b; pentafluorobenzonitrile, c) were prepared, and their solution properties were investigated by 31P NMR measurements. The catalytic activities and enantioselectivities for IIa–c catalysedhydrogenation of some prochiral acids were very similar to those provided
Asymmetric synthesis of (R)- and (S)-4-(substituted benzyl)dihydrofuran-2(3H)-ones: an application of the ruthenium-binap complex-catalysed asymmetric hydrogenation of alkylidenesuccinic acids
A concise synthesis of (S)- or (R)-4-(substituted benzyl)dihydrofuran-2(3H)-ones (1) with high enantiomeric purity is presented. (S)- or (R)-(Substituted benzyl)succinic acids (6) 97% enantiomeric excess) were first prepared by Ru2Cl4[(R)- or (S)-binap)]2(NEt3) catalysed asymmetrichydrogenation of (substituted benzylidene)succinic acids. The diacids (6) were converted into (R)- or (S)-2-(substituted
Berner; Leonardsen, Justus Liebigs Annalen der Chemie, 1939, vol. 538, p. 27
作者:Berner、Leonardsen
DOI:——
日期:——
Preparation of (S)-2-substituted succinates by stereospecific reductions of fumarate and derivatives with resting cells of Clostridium formicoaceticum
作者:Richard Eck、Helmut Simon
DOI:10.1016/s0040-4020(01)85677-5
日期:1994.1
Fumarate derivatives have been reduced to (S)-2-methylsuccinate 2a, (S)-2-ethylsuccinate 3a and (S)-2-chlorosuccinate 4a in up to 1 M concentrations with Clostridium formicoaceticum. Formate was the electron donor and viologens or anthraquinone-2,6-disulphonate acted as artificial electron mediators. Reductions with freeze-dried cells in (H2O)-H-2-buffers led to the (2R,3S)-[2,3-H-2]-dideuterated succinate derivatives. The productivity numbers(1) ranged from 450 to 5000 and the enantiomeric excess of all (S)-2-substituted succinates was greater than or equal to 99%.