摘要:
A process for the preparation of an enantiomerically enriched 2-substituted succinic acid derivative of formula 2, which comprises asymmetric hydrogenation of the dehydro precursor of formula 7 or 8, or a mixture thereof wherein R1 and R2 are independently H, a salt-forming cation, or an organic group of up to 30 C atoms, and R3 and R4 are independently H or an organic group of up to 30 C atoms, provided that R3 and R4 are not both H, in the presence of a transition metal complex of a chiral phosphine ligand having the partial formula 10 wherein n is 0 to 6 and R represents at least one non-hydrogen organic group of up to 30 C atoms.
摘要:
The present invention pertains to a process for the preparation of an enantiomerically enriched chiral carboxylic acid derivative having the partial formula: C—C—C—COOX wherein X is a cation, comprising formation of a dehydro precursor salt having the partial formula: C═C—C—COOX by reaction of the corresponding precursor acid with an at least substantially stoichiometric amount of base, and asymmetric hydrogenation of the salt in the presence of a transition metal complex of a chiral phosphine ligand.
摘要:
The present invention concerns novel complexes, suitable in particular for use as catalysts in the asymmetric hydrogenation of ketones, of formula 1 or a diastereoisomer thereof, wherein each Ar is an aromatic or heteroaromatic group of up to 20 atoms; X is halide or carboxylate; and R1, R2, R3, and R4 are independently hydrogen, aryl or alkyl, optionally linked or part of a ring.
摘要:
A supported catalyst comprises a cationic rhodium(I) complex of the formula wherein R1 and R2 are the same or different hydrocarbon groups of up to 30 C atoms, or R1 and R2 are linked to form a ring, and a heterogeneous support medium that provides anionic binding sites. Such a complex is particularly useful as a catalyst in a process of hydrogenating an aldehyde to produce the corresponding primary alcohol.
摘要:
A novel phosphine ligand is an enantiomerically enriched compound of formula 5 or the opposite enantiomer thereof, wherein Ar1 and Ar2 represent the same or different aromatic groups of up to 20 C atoms. A transition metal complex of this ligand is useful as a catalyst in stereoselective hydrogenation.
摘要:
This invention provides a method of making (S)-(+)-3-(aminomethyl)-5-methylhexanoic acid (pregabalin) or a salt thereof via an asymmetric hydrogenation synthesis. Pregabalin is useful for the treatment and prevention of seizure disorders, pain, and psychotic disorders. The invention also provides intermediates useful in the production of pregabalin.
摘要:
An enantiomerically enriched compound of formula (4) or the opposite enantiomer thereof, wherein R is C1-10 alkyl. This compound, in the form of a transition metal complex, is useful as a catalyst for stereoselective hydrogenation.