Dsm IP Assets B.v.

Dsm N.v.

Johannes Gerardus Vries De

Quirinus B Broxterman

Gerardus Karel Maria Verzijl

Adriaan Jacobus Minnaard

Michel Berg Van Den

Floris Jacobus Parlevliet

Ben Feringa

Andreas Hendrikus Maria Vries De

Catalyst for the asymmetric (transfer) hydrogenation represented by the formula MLXS, where M is a transition metal, to be chosen from rhodium and ruthenium, and X is a counter ion and S is a ligand, a ranges from 0.5 to 3 and b and c, each independently, range from 0 to 2, and L is a chiral ligand having the formula (1), where Ctogether with the two 2 O-atoms and the P-atom forms a substituted or non-substituted ring with 2-4 C-atoms, Rand Reach independently represent H, an optionally substituted alkyl, aryl, alkaryl or aralkyl group or may form a (heterocyclic) ring together with the N-atom to which they are bound. And a process for the asymmetric (transfer) hydrogenation of an olefinically unsaturated compound, ketone, imine or oxime derivate in the presence of a hydrogen donor and of a catalyst, use being made of a catalyst represented by formula MLXS, where M is a transition metal, to be chosen from rhodium, iridium and ruthenium, X is a counter ion, S is a ligand, a ranges from 0.5 to 3 and b and c range from 0 to 2, and L is a chiral ligand having the formula (1), where Ctogether with the two 2 O-atoms and the P-atom forms a substituted or non-substituted ring with 2-4 C-atoms; and Rand Rare as defined above.

Catalyst for asymmetric (transfer) hydrogenation

Process for regenerating a Pd catalyst after a homogeneously catalyzed C&#x2014;C coupling reaction in which the Pd catalyst precipitates, is separated from the reaction mixture and subsequently treated with Ior Br. The Pd catalyst can then be used in a subsequent reaction run. Preferably between 1 and 3 mole equivalents of Ior Br, relative to the quantity of Pd catalyst is used The C&#x2014;C coupling reaction is preferably carried out in the presence of a support material. The C&#x2014;C coupling reaction may be for example a Heck reaction, a Suzuki reaction or a cross-coupling reaction.

Process for regenerating Pd catalysts

Method for the preparation of an enantiomerically enriched ester, in which a mixture of the enantiomers of the corresponding secondary alcohol is subjected, in the presence of an acyl donor, to an enantioselective conversion in the presence of a racemisation catalyst upon which the ester is formed and an acyl donor residue is obtained, and in which the acyl donor residue is irreversibly removed from the phase in which the enantioselective conversion takes place. Preferably the enantioselective conversion is carried out enzymatically and a transfer hydrogenation catalyst is used as racemisation catalyst. The secondary alcohol can be formed in situ from the corresponding ketone, in the presence of a hydrogen donor. It is also possible to use a mixture of the secondary alcohol and the corresponding ketone as substrate. Preferably the acyl donor is chosen so that the acyl donor residue is converted in situ into another compound and/or the acyl donor residue is removed via distillation under reduced pressure. The enantiomerically enriched esters obtained can subsequently be converted into the corresponding enantiomerically enriched alcohols, which are desirable intermediate products in the preparation of liquid crystals, agro chemicals or pharmaceuticals.

Process for the preparation of enantiomerically enriched esters and alcohols

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Maastricht, Netherlands

Johannes Gerardus Vries De