Catalytic hydrogenation of carbon-heteroatom double bonds

A process for hydrogenating a substrate containing a carbon-heteroatom double bond, which includes the step of reacting the substrate with hydrogen gas in the presence of a hydrogenation catalyst and of a base, wherein the hydrogenation catalyst is a transition metal complex of the formula (I)

• [X Y Ru (P R1R2R3) (P-Z-N)] (I)
• where
• X, Y are each independently a hydrogen atom, halogen atom, C1-8alkoxy or C1-8acyloxy group, or a coordinatively bound organic solvent molecule containing at least one heteroatom having at least one free electron pair, in which case the charge of the resulting cationic complex is balanced by an anion,
• R1, R2, R3 are each independently an alkyl, alkyloxy, alkylthio, dialkyamino, cycloalkyl, cycloalkyloxy, cycloalkylthio, dicycloalkylamino, aryl, aryloxy, arylthio or diarylamino group, said groups being unsubstitued or substituted by 1,2 or 3 radicals which are each independently selected from C1-4alkyl groups and C1-4alkoxy groups, or one of the R1, R2, R3 radicals is as defined above and the remaining 2 radicals which, linked either via an oxygen bridge or directly to the phosphorus atom, form, including the phosphorus atom, an unsubstituted or substituted 4- to 8-membered ring,
• P-Z-N is a bidentate ligand which contains an sp2-hybridized nitrogen atom and is of the formula (II)
• wherein
• R4, R5 are each independently a linear, branched or cyclic unsubstituted or substituted C1-8alkyl or C2-8alkenyl group;
• unsubstituted or substituted C6-18aryl, C3-18heteroaryl, C3-8cycloalkyl, (C1-8Alkyl)1-3-(Hetero)Aryl, whereby possible substituents are halogen, organohalogen group, O(C1-8)alkyl, N(C1-8alkyl)2;
• or R4 and R5 together are a saturated or aromatic ring composed of 5 to 10 atoms including the phosphorus atom,
• Ca, Cb are each a part of an unsubstituted or substituted (hetero)aryl having at least 6 π-electrons,
• R6 is a hydrogen atom, a linear, branched or cyclic unsubstituted or substituted C1-10alkyl or C2-10alkenyl group, an unsubstituted or substituted aromatic ring, a —OR6′ or —NR6′R6″radical, wherein R6′ and R6″ are as defined for R6,
• R7 is a hydrogen atom, a linear, branched or cyclic C1-10alkyl or C2-10alkenyl group, or an R7′CO or R7′SO2 radical where R7′ is a C1-8alkyl or aryl group, or
• R6 and R7 together are an unsaturated (hetero)cycle composed of unsubstituted or substituted 5 to 10 ring atoms, including the carbon and the nitrogen atom to which R6 and R7 are bonded, and including or not including further heteroatoms, whereby said substrate to be hydrogenated is a prochiral monocyclic or polycyclic aryl ketone or heteroary ketone, optionally substituted by linear or branched C1-8alkyl, C1-8alkoxy group, or halogen atoms.