197900-84-8Relevant academic research and scientific papers
Oxa-spiral diphosphine ligand and application thereof in alpha, beta-unsaturated carboxylic acid asymmetric hydrogenation
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Paragraph 0056-0058, (2019/04/04)
The invention provides an oxa-spiral diphosphine ligand. The oxa-spiral diphosphine ligand has a structure shown by a general formula (I) as shown in description, wherein R1, R2, R3 and R4 in the general formula (I) are same and are alkyl, alkoxy, aryl, aroxyl, or hydrogen atoms; R1, R2, R3 and R4 comprise forms of ring formation, non-ring formation, any two ring formation or multiple-ring formation between pairs; R5 and R6 are alkyl, aryl or hydrogen atoms; and R7 and R8 are alkyl or benzyl or aryl. The invention further provides application of the oxa-spiral diphosphine ligand O-SDP in the alpha, beta-unsaturated carboxylic acid asymmetric hydrogenation. A complex of the oxa-spiral diphosphine ligand O-SDP and ruthenium has excellent activity and enantioselectivity in the asymmetric hydrogenation of the alpha, beta-unsaturated carboxylic acid in multiple types, and a chiral carboxylic acid product is obtained with the enantioselectivity being up to 99%. The synthesis method can be applied to the construction of a core skeleton of chemical molecules with important activity, wherein the chemical molecules comprise Paroxetine, Femoxetine, nipecotic acid and Sacubitril.
Process for the preparation of enantiomerically enriched cyclic beta-aryl or heteroaryl carbocyclic acids
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Page/Page column 18; 19, (2008/06/13)
The present invention relates to a process for the preparation of cis substituted cyclic β-aryl or heteroaryl carboxylic acid derivatives in high diastereo- and enantioselectivity by enantioselective hydrogenation in accordance with the following scheme w
