A chiral hydroxyl bisphospholane, 1,2-bis[(2S,3S,4S,5S)-3,4-dihydroxyl-2,5-dimethylphospholanyl]benzene (4), was synthesized from readily available d-mannitol. Its Rh(I) complex catalyzes asymmetric hydrogenation of dehydroaminoacids and their ester derivatives with excellent enantioselectivities (98 to >99% ee).
Method for the Production of Optically Active Carbonyl
申请人:Jakel Christoph
公开号:US20080269528A1
公开(公告)日:2008-10-30
The present invention relates to a process for preparing optically active carbonyl compounds by asymmetrically hydrogenating α,β-unsaturated carbonyl compounds in the presence of optically active transition metal catalysts which are soluble in the reaction mixture and have at least one carbon monoxide ligand. The present invention especially relates to a process for preparing optically active aldehydes or ketones, in particular citronellal, by asymmetrically hydrogenating the corresponding optically active α,β-unsaturated aldehydes or ketones.
Phospholane salts and their use in enantioselective hydrogenation
申请人:Kesselgruber Martin
公开号:US20070015925A1
公开(公告)日:2007-01-18
Process for preparing a catalyst solution by reacting metal complexes and diphosphines in the presence of an inert organic solvent, which is characterized in that a) an uncharged or cationic metal complex having a TM8 metal as central atom, and b) a salt of a chiral ditertiary diphosphine which has one or two phospholane groups which are bound to a carbon chain having from 2 to 4 carbon atoms and contain anions selected from the group consisting of R
C
COO
−
, R
C
SO
3
−
, BF
4
−
, PF
6
−
, AsF
6
−
, SbF
6
−
, B(C
6
F
5
)
4
−
and B(3,5-bistrifluoromethylphenyl)
4
−
, are reacted with one another, where the ratio of the components a) and b) is from 1:1 to 1:2 and R
C
is C
1
-C
6
-haloalkyl, C
5
-C
10
-halocycloalkyl or C
6
-C
10
-haloaryl.
The invention comprises a process for the preparation and isolation of a non-amorphous cationic rhodium complex having the formula: [Rh(ligand)
m
(diolefin)]
+
X
−
, wherein the ligand is an enantiomerically enriched organic compound possessing one or two ligating phosphorus atoms.