Organic compounds

Abstract

A process for the hydrogenation of a substrate comprising a carbon heteroatom double bond in the presence of a transition metal complex comprising a tridentate or bisdentate-ligand containing a nitrogen, sulphur and phosphorus atom, of which at least the N- and P- and optionally also the S-atom coordinates with the transition metal.

Claims

1. A transition metal complex according to the formula:
MX.sub.2[SNP]Y wherein M is a group VIII transition metal and SNP represents a tridentate or bisdentate ligand containing a nitrogen, sulphur and phosphorus atom, of which at least the N- and P- and optionally also the S-atom coordinates with the transition metal, each X is independently selected from a halide, hydroxyl, alkoxy, acyloxy and amido; and each Y is independently selected from a monodentate phosphine, a carbon monoxide (CO) ligand, a nitrosyl group and a RCN group, wherein R is alkyl or aryl, wherein the tridentate or bisdentate ligand is represented by the formula ##STR00040## wherein R.sub.1 and R.sub.2 are independently selected from H, or C.sub.1 to C.sub.20 alkyl and aryl, or R.sub.1 and R.sub.2 are connected such that together with the sulphur and carbon atoms to which they are attached, they form a heteroaliphatic or heteroaromatic ring; R.sub.3 through R.sub.7 are independently selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl group; or R.sub.2 and R.sub.3; R.sub.3 and R.sub.4; or R.sub.2 and R.sub.4, together with the carbon atoms to which they are attached form a 5- or 6-membered aliphatic ring, which is optionally unsaturated; and/or R.sub.5 and R.sub.6; R.sub.5 and R.sub.7; or R.sub.6 and R.sub.7, together with the carbon atoms to which they are attached form a 5- or 6- membered aliphatic ring, which is optionally unsaturated; R.sub.8 and R.sub.9 independently are selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl or heteroaryl group; a and b are independently 0, 1 or 2; n is 0 or 1; and represents a single or a double bond, provided that when R.sub.2 is H or C.sub.4 to C.sub.20 alkyl represents a single bond; and when n is 1 each N represents a carbon-nitrogen single bond; whereas when n is 0, one N is a carbon-nitrogen single bond and the other N is a carbon-nitrogen double bond.

2. A complex according to claim 1 wherein the nitrogen atom on the tridentate or bisdentate ligand forms part of an amine group or an imine group; the sulphur atom forms part of an aliphatic group or forms part of an aromatic ring; and the phosphorus atom forms part of a phosphine group.

3. A complex according to claim 1, wherein the nitrogen atom-containing group is flanked on one side by the phosphorus atom-containing group, and on the other side by the sulphur atom-containing group.

4. A complex according to claim 1, wherein the tridentate or bisdentate ligand is represented by the formula ##STR00041## wherein R.sub.1 and R.sub.2 are independently selected from H, or C.sub.1 to C.sub.20 alkyl or aryl, or R.sub.1 and R.sub.2 are connected such that together with the sulphur and carbon atoms to which they are attached, they form a heteroaliphatic or heteroaromatic ring; R.sub.3 through R.sub.7 are independently selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl group; or R.sub.2 and R.sub.3; R.sub.3 and R.sub.4; or R.sub.2 and R4, together with the carbon atoms to which they are attached form a 5- or 6-membered aliphatic ring, which is optionally unsaturated; and/or R.sub.5 and R.sub.6; R.sub.5 and R.sub.7; or R.sub.6 and R.sub.7, together with the carbon atoms to which they are attached form a 5- or 6-membered aliphatic ring, which is optionally unsaturated; R.sub.8 and R.sub.9 independently are selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl or heteroaryl group; a and b are independently 0, 1 or 2; n is 0 or 1; and represents a single or a double bond, provided that when R.sub.2 is H or C.sub.4 to C.sub.20 alkyl represents a single bond; and when n is 1 each N represents a carbon-nitrogen single bond; whereas when n is 0, one N is a carbon-nitrogen single bond and the other N is a carbon-nitrogen double bond.

5. A complex according to claim 1, wherein the tridentate or bisdentate ligand is represented by the formula selected from the group consisting of ##STR00042## wherein R.sup.10 is a moiety selected from C.sub.1-10 alkyl, aryl, heteroaryl, alkenyl, nitrile and halide, and m is 0, 1, 2 or 3.

6. A complex according to claim 1, wherein the metal M is ruthenium or osmium.

7. A tridentate or bisdentate ligand L presented by the formula ##STR00043## wherein R.sub.1 and R.sub.2 are independently selected from H, and C.sub.1 to C.sub.20 alkyl or aryl, or R.sub.1 and R.sub.2 are connected such that together with the sulphur and carbon atoms to which they are attached, they form a heteroaromatic or heteroaliphatic ring, and wherein said heteroaromatic ring is not a 5-membered heterocycle containing both S and N atoms; R.sub.3 through R.sub.7 are independently selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl group; or R.sub.2 and R.sub.3; R.sub.3 and R.sub.4; or R.sub.2 and R.sub.4, together with the carbon atoms to which they are attached form a 5- or 6-membered aliphatic ring, which is optionally unsaturated; and/or R.sub.5 and R.sub.6; R.sub.5 and R.sub.7; or R.sub.6 and R.sub.7, together with the carbon atoms to which they are attached form a 5- or 6-membered aliphatic ring, which is optionally unsaturated; R.sub.8 and R.sub.9 independently are selected from H; a C.sub.1 to C.sub.20 linear or branched alkyl group or alkenyl group; a C.sub.3 to C.sub.8 cyclic alkyl group; and a C.sub.5 to C.sub.10 aryl or heteroaryl group; a and b are independently 0, 1 or 2; n is 0 or 1; and represents a single or a double bond, provided that when R.sub.2 is H or C.sub.4 to C.sub.20 alkyl, represents a single bond; and when n is 1 each N represents a carbon-nitrogen single bond; whereas when n is 0, one N is a carbon-nitrogen single bond and the other N is a carbon-nitrogen double bond; with the proviso that the ligand L is not ##STR00044## wherein the tridentate or bisdentate ligand is represented by the formula selected from the group consisting of ##STR00045## wherein R.sup.10 is a moiety selected from C.sub.1-10 alkyl, aryl, heteroaryl, alkenyl, nitrile and halide, and m is 0,1,2 or 3.

8. A tridentate or bisdentate ligand according to claim 7 represented by the formula selected from the group consisting of ##STR00046##

Description

GENERAL ANALYTICAL CONDITIONS

(1) Non-polar GCMS: 50 C./2 min, 20 C./min 200 C., 35 C./min 270 C. GC/MS Agilent 5975C MSD with HP 7890A Series GC system. Non-polar column: BPX5 from SGE, 5% phenyl 95% dimethylpolysiloxan 0.22 mm0.25 mm12 m. Carrier Gas: Helium. Injector temperature: 230 C. Split 1:50. Flow: 1.0 ml/min. Transfer line: 250 C. MS-quadrupol: 106 C. MS-source: 230 C.

EXAMPLE 1: RuCl2(2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)ethanamine)PPh3 1

(2) ##STR00010##

(3) Under nitrogen and stirring NaBH(OAc).sub.3 (4.4 g, 20 mmol) is added to 2-(diphenylphosphino)-ethanamine (3 g, 12.4 mmol) and thiophene-2-carbaldehyde (1.6 g, 13.7 mmol) in 1,2-dichloroethane (75 ml). After 18 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 (100 ml) and extracted with ethyl acetate. The organic layers are washed with water and conc. aqueous NaCl. The aqueous phase is re-extracted with ethyl acetate. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 4.6 g of a yellow oil which is taken up in t-butyl methyl ether and purified by flash chromatography over silica gel using eluent t-butyl methyl ether. The first fraction (1.85 g) contains the double alkylation product (tertiary amine) and is discarded, the second fraction (1.1 g, 27%) contains SNP-ligand 2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)-ethanamine as yellowish oil. Analytical data:

(4) ##STR00011##

(5) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.38-7.43 (4 H, Ar), 7.28-7.31 (6 H, Ar), 7.2 (m, 1 H, Thiophen-CH), 6.9 (m, 1 H, Thiophen-CH), 6.85 (m, 1 H, Thiophen-CH), 3.9 (d, J=1.01 Hz, 2 H, CH.sub.2N), 2.69-2.84 (m, 2 H, NCH.sub.2CH.sub.2P), 2.20-2.30 (m, 2 H, NCH.sub.2CH.sub.2P), 1.7 (s, 1 H, NH) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 144.6 (s), 138.8 and 138.7 (s), 132.7 and 132.6 (s), 128.6 and 128.5 (d), 128.4 (d), 126.5 (d), 124.6 (d), 124.15 (d), 48.05 (t), 45.9 and 45.7 (t), 28.9 and 28.8 (t) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 21.5 ppm. MS (EI) (%) (m/z): 325 ([M].sup.+, 17%), 292 ([MHS].sup.+, 20%), 268 ([M-C.sub.2HS].sup.+, 15%), 186 ([HPPh.sub.2].sup.+, 100%), 97 ([CH.sub.2-thiophen].sup.+, 50%).

(6) SNP-ligand 2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)ethanamine (0.16 g, 0.5 mmol) and RuCl.sub.2(PPh.sub.3) 3 (0.5 g, 0.5 mmol) in dichloromethane (15 ml) are heated under reflux, stirring and nitrogen for 24 h. At room temperature hexane (60 ml) are added. The precipitate is filtered, washed with hexane (320 ml) and dried under reduced pressure to give complex 1 (0.21 g, 55%) as a brick red powder. Analytical data of 1:

(7) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 2.3-2.43 (m, 1 H), 2.76-2.87 (m, 1 H), 3.3-3.5 (m, 2 H), 4.07-4.15 (m, 1 H), 4.39-4.46 (m, 1 H), 4.56-4.68 (m, 1 H), 6.00 (d, J=5.3 Hz, 1 H), 6.85-7.58 (m, 30 H) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 42.79 (d, .sup.2J.sub.P,P=34 Hz, 1 P), 60.0 (d, .sup.2J.sub.P,P=33 Hz, 1 P). MS (EI) (%) (m/z): 480 ([MCl+Na].sup.+, 748%). Anal. calcd. for C.sub.37H.sub.35Cl.sub.2NP.sub.2RuS: C, 58.50%; H, 4.64%; N, 1.84%. Found: C, 58.42%; H, 4.92%; N, 1.74%.

EXAMPLE 2: RuCl2(2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)ethanamine)PPh3 2

(8) ##STR00012##

(9) Under nitrogen and stirring NaBH(OAc).sub.3 (1.5 g, 6.6 mmol) is added to 2-(diphenylphosphino)ethanamine (1 g, 4.1 mmol) and thiophene-2-carbaldehyde (0.7 g, 4.1 mmol) in 1,2-dichloroethane (25 ml). After 19 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 and extracted with ethyl acetate. The organic layers are washed with water and conc. aqueous NaCl. The aqueous phase is re-extracted with ethyl acetate. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 1.7 g of a yellow oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. Evaporation of the solvent gives SNP-ligand N-(benzo[b]thiophen-2-ylmethyl)-2-(diphenyl-phosphino)ethanamine (0.32 g, 21%). Analytical data:

(10) ##STR00013##

(11) .sup.1H-NMR (CDCl.sub.3, 400 MHz): 7.79 (d, 1 H), 7.68 (d, 1 H), 7.4-7.45 (4 H), 7.25-7.35 (8 H), 7.05 (s, 1 H), 4.0 (d, 2 H, CH.sub.2N), 2.85 (m, 2 H, NCH.sub.2CH.sub.2), 2.3 (m, 2 H, NCH.sub.2CH.sub.2), 1.72 (br. s., 1 H, NH) ppm. .sup.13C-NMR (CDCl.sub.3, 400 MHz): 145.1 (s), 139.8 (s), 139.7 (s), 138.4 and 138.3 (2 s), 132.8 and 132.65 (d), 128.7 and 128.5 (d), 128.4 (d), 129.01 (s, 1 C), 124.1 (d), 123.8 (d), 123.1 (d), 122.4 (d), 121.2 (d), 48.8 (t), 45.85 and 45.65 (t), 29.1 and 28.95 (t) ppm. .sup.31P-NMR (CDCl.sub.3, 400 MHz): 20.9 ppm. MS (EI) (%) (m/z): 375 ([M].sup.+, 23%), 324 (7%), 318 (18%), 266 (22%), 200 (15%), 199 (17%), 186 ([HPPh.sub.2].sup.+, 100), 185 (10%), 183 (17%), 162 (15%), 152 (14%), 147 (48%), 121 (13%), 108 (30%).

(12) SNP-Ligand N-(benzo[b]thiophen-2-ylmethyl)-2-(diphenylphosphino)ethanamine (0.17 g, 0.45 mmol) and RuCl.sub.2(PPh.sub.3) 3 (0.45 g, 0.45 mmol) in dichloromethane (13 ml) are heated under reflux, stirring and nitrogen for 24 h. At room temperature hexane (60 ml) are added ed. The precipitate is filtered, washed with hexane and dried under reduced pressure to give complex 2 (0.32 g, 88%) as a pink powder. Analytical data:

(13) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 6.9-7.8 (30 H), 5.85 (d), 4.8 (m), 4.6 (t), 4.2 (m), 3.3-3.7, 2.85 (m), 2.35 (m), 1.6 (1 H), with 6 H from 2.35 to 5.85 ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 57.2 (d), 43.1 (d). MS (EI in MeOH, HCO.sub.2H, %, m/z): 784 ([MClHCl+HCO.sub.2H].sup.+, 100%), 738 ([MClHCl].sup.+, 15%). Anal. calcd. for C.sub.41H.sub.37Cl.sub.2NP.sub.2RuS: C, 60.82%; H, 4.61%; N, 1.73%. Found: C, 60.25%; H, 4.53%; N, 1.56%.

EXAMPLE 3: RuCl2(2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine)PPh3 3

(14) ##STR00014##

(15) Methylthioethanal was prepared as described in Synthesis 7, 659 (1987) from (2,2-dimethoxyethyl)(methyl)sulfane.

(16) Under nitrogen and stirring NaBH(OAc).sub.3 (3 g, 13.3 mmol) is added to 2-(diphenylphosphino)-ethanamine (2 g, 8.3 mmol) and methylthioethanal (0.85 g, 9.1 mmol) in 1,2-dichloroethane (50 ml). After 18 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 and extracted with ethyl acetate. The organic layers are washed with water and conc. aqueous NaCl. The aqueous combined aqueous layers are re-extracted with ethyl acetate. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 2.83 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. Evaporation of the solvent gives SNP-ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine (0.79 g, 31%). Analytical data:

(17) ##STR00015##

(18) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.45 (4 H, Ar), 7.3-7.35 (6 H, Ar), 2.7-2.8 (4 H), 2.5-2.6 (m, 2 H), 2.2-2.3 (m, 2 H), 2.05 (3 H), 1.7 (br, 1 H, NH) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.8 (s), 132.7 (d), 128.4-128.8 (2 d), 47.8 (t), 46.3 and 46.1 (t), 34.4 (t), 29.1 and 28.9 (t), 15.1 (q, SMe) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.7 ppm. GSMS (EI) (%) (m/z): 288 ([MCH.sub.3].sup.+, 8%), 256 ([M+OMeSH].sup.+, 80%), 242 (8%), 199 (19%), 185 (100%), 183 (89%), 152 (11%), 121 (27%), 108 (20%), 107 (21%), 91 (11%), 75 (43%), 61 (14%).

(19) SNP-Ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine (0.165 g, 0.54 mmol) and RuCl.sub.2(PPh.sub.3).sub.3 (0.52 g, 0.54 mmol) in dichloromethane (15 ml) are heated under reflux, stirring and nitrogen for 16 h. At room temperature hexane (60 ml) are added. The precipitate is filtered, washed with hexane and dried under reduced pressure to give complex 3 (0.27 g, 86%) as a greenish powder. Analytical data:

(20) .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 46.1 and 44.7 (2 d, 30.5 Hz, major isomer), 46.6 and 44.4 (2 d, 32.5 Hz, minor isomer). MS (EI in MeOH, HCO.sub.2H, %, m/z): 776 ([M+0+Na].sup.+, 100%), 735 and 737 ([M].sup.+, 15%), 718 ([MCl+O].sup.+, 35%), 702 ([MCl].sup.+, 55%). Anal. calcd. for C.sub.35H.sub.37Cl.sub.2NP.sub.2RuS: C, 56.99%; H, 5.06%; N, 1.9%. Found: C, 55.59%; H, 5.00%; N, 2.17%.

EXAMPLE 4: RuCl2(2-(diphenylphosphino)-N-(2-(n-butylthio)ethyl)ethanamine)PPh3 4

(21) ##STR00016##

(22) For the synthesis of n-butylthioethanal see N. A. Keiko et al. Arkivoc 127-138 (2011).

(23) Under nitrogen and stirring NaBH(OAc).sub.3 (3 g, 13.3 mmol) is added to 2-(diphenylphosphino)-ethanamine (2 g, 8.3 mmol) and n-butyllthioethanal (1.2 g, 9.1 mmol) in 1,2-dichloroethane (50 ml). After 22 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 and is extracted with DCE. The organic layers are washed with conc. aqueous NaCl. The aqueous phase is re-extracted with DCE. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 3.15 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. In a first fraction byproduct 2-(butylthio)-N-(2-(butylthio)ethyl)-N-(2-(diphenylphosphino)ethyl)ethanamine (0.72 g, 19%, after solvent evaporation) is separated. Analytical data:

(24) ##STR00017##

(25) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4 (4 H, Ar), 7.3 (6 H, Ar), 2.7-2.6 (6 H), 2.45-2.55 (8 H), 2.2 (2 H), 1.5-1.6 (4 H), 1.35-1.45 (4 H), 0.9 (t, 6 H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.8 (s), 132.65 (d), 130.55 (d), 128.55 (d), 53.9 (t), 50.2 (t), 32.0 (t), 29.8 (t), 25.7 (t), 22.0 (t), 13.5 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.0 ppm. MS (EI) (m/z): 404 ([MC4H9].sup.+), 373 (23%), 372 (90%), 358 (100%), 288 (6%), 256 (8%), 186 (9%), 185 (61%), 183 (25%), 117 (55%), 61 (16%). 57 (11%). IR (film): 3052 (w), 2954 (m), 2926 (m), 2870 (m), 1738 (w), 1586 (w), 1480 (w), 1457 (m), 1434 (m), 1377 (w), 1294 (w), 1192 (m), 1095 (m), 1069 (w), 1026 (w), 998 (w), 914 (w), 737 (m), 695 (s).

(26) Evaporation of the solvent from the second fraction gives SNP-ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine (0.72 g, 25%). Analytical data:

(27) ##STR00018##

(28) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.45 (4 H, Ar), 7.3-7.35 (6 H, Ar), 2.7 (4 H), 2.6 (m, 2 H), 2.5 (2 H), 2.3 (m, 2 H), 1.6 (br, 1 H, NH), 1.5 (m, 2 H), 1.4 (m, 2 H), 0.9 (t, 3 H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.85 (s), 132.65 (d), 130.55 (d), 128.45 (d), 48.5 (t), 46.2 (t), 32.3 (t), 31.9 (t), 31.6 (t), 28.95 (t), 22.0 (t), 13.5 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.7 ppm. MS (EI) (m/z): 346 ([M+H].sup.+, 289 (10%), 288 (55%), 257 (18%), 256 ([M+OBuSH].sup.+, 100%), 242 (20%), 199 (13%), 186 (18%), 185 (87%), 183 (31%), 69 (20%). IR (film): 3051 (w), 2926 (m), 2871 (w), 1953 (w), 1886 (w), 1812 (w), 1737 (w), 1671 (w), 1585 (w), 1479 (w), 1456 (m), 1433 (m), 1376 (w), 1331 (w), 1272 (w), 1240 (w), 1184 (w), 1117 (m), 1068 (w), 998 (w), 737 (m), 694 (s).

(29) SNP-ligand 2-(diphenylphosphino)-N-(2-(n-butylthio)ethyl)ethanamine (0.25 g, 0.7 mmol) and RuCl.sub.2(PPh.sub.3).sub.3 (0.71 g, 0.7 mmol) in dichloromethane (15 ml) are heated under reflux, stirring and nitrogen for 14 h. At room temperature hexane (100 ml) are added. The precipitate is filtered, washed with hexane and dried under reduced pressure to give complex 4 (0.44 g, 78%) as an orange powder. Analytical data:

(30) .sup.1H-NMR (400 MHz, CD.sub.2Cl.sub.2): 6.9-7.4 (25 H), 4.5 and 4.7 (1 H), 2.3-3.7 (9 H), 1.55 (2H), 1.0-1.5 (4 H), 0.8 (t, 3H). .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 45.6 and 45.9 (2 d), 44.7 and 44.8 (2 d). MS (ESI(+) in MeOH, HCO.sub.2H, %, m/z): 754 ([MClHCl+HCO.sub.2H].sup.+, 100%, identical with calculated isotope cluster), 744 ([MCl].sup.+, 100%). Anal. calcd. For C.sub.38H.sub.43Cl.sub.2NP.sub.2RuS: C, 58.53%; H, 5.56%; N, 1.80%. Found: C, 57.21%; H, 5.44%; N, 1.75%. IR (ATR): 3162 (w), 3059 (w), 2947 (w), 2859 (w), 1585 (w), 1480 (w), 1454 (w), 1432 (m), 1303 (w), 1267 (w), 1187 (w), 1156 (w), 1138 (w), 1088 (m), 1067 (w), 1027 (w), 1006 (w), 983 (m), 914 (w), 865 (w), 799 (w), 751 (w), 740 (m), 737 (m), 691 (s), 657 (m), 619 (m).

EXAMPLE 5: RuCl2(2-(diphenylphosphino)-N-(2-(n-octylthio)ethyl)ethanamine)PPh3 5

(31) ##STR00019##

(32) For the synthesis of n-octylthioethanal see N. A. Keiko et al. Arkivoc 127-138 (2011).

(33) Under argon and stirring NaBH(OAc).sub.3 (2.8 g, 12.5 mmol) is added to 2-(diphenylphosphino)-ethanamine (1.9 g, 2.8 mmol) and n-octyllthioethanal (1.6 g, 8.6 mmol) in 1,2-dichloroethane (50 ml). After 22 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 and is extracted with DCE. The organic layers are washed with conc. aqueous NaCl. The aqueous phase is re-extracted with DCE. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 3.6 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel with eluent ethyl acetate to give after evaporation of the solvent 0.64 g (20%) of the ligand as colorless oil. Analytical data:

(34) ##STR00020##

(35) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.5 (4 H, Ar), 7.25-7.35 (6 H, Ar), 2.8 (4 H), 2.6 (m, 2 H), 2.5 (m, 2 H), 2.3 (m, 2 H), 1.8 (br, 1 H, NH), 1.5-1.6 (m, 2 H), 1.3-1.4 (4 H), 1.25 (6 H), 0.9 (t, 3H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.35 (s), 132.7 (d), 128.6 (d), 128.4 (d), 48.4 (t), 46.25 (t, CH.sub.2P), 32.3 (t), 32.0 (t), 31.8 (t), 29.8 (t), 29.2 (t), 29.1 (t), 29.0 (t), 28.9 (t), 22.7 (t), 14.1 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.6 ppm. MS (EI) (m/z): 400 ([MH].sup.+, 1%), 289 (12%), 288 (57%), 257 (19%), 256 ([M+OOctSH].sup.+, 100%), 242 (19%), 200 (7%), 199 (8%), 186 (15%), 185 (56%), 183 (26%), 121 (7%).

(36) SNP-ligand 2-(diphenylphosphino)-N-(2-(n-octylthio)ethyl)ethanamine (0.5 g, 1.25 mmol) and RuCl.sub.2(PPh.sub.3) 3 (0.86 g, 0.87 mmol) in dichloromethane (30 ml) are heated under reflux, stirring and nitrogen for 24 h. At room temperature hexane (100 ml) is slowly added under stirring. The orange precipitate is filtered, washed with hexane (320 ml) and dried under reduced pressure to give crude complex 5 (0.51 g, 71%) as an orange powder which is taken up again in dichoromethane (30 ml) and treated again with hexane (150 ml), slowly and under stirring. The orange precipitate is filtered, washed with hexane (320 ml) and dried under reduced pressure to give complex 5 (0.3 g, 29%) as an orange powder

(37) .sup.1H-NMR (400 MHz, CD.sub.2Cl.sub.2): 6.9-7.5 (25 H), 4.55 and 4.8 (1 H), 2.3-3.6 (10 H), 1.0-1.6 (12 H), 0.9 (t, 3H). .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 46.3, 46.1, 45.8, 45.6 and 44.7, 44.5, 44.1, 44.0. Anal. calcd. For C.sub.42H.sub.51Cl.sub.2NP.sub.2RuS: C, 60.35%; H, 6.15%; N, 1.68%. Found (after 1.sup.st precipitation): C, 60.00%; H, 6.31%; N, 1.52%. Found (after 2.sup.nd precipitation): C, 60.24%; H, 6.24%; N, 1.83%. IR (ATR): 3162 (w), 3054 (w), 2957 (w), 2921 (w), 2853 (w), 1481 (w), 1455 (w), 1432 (m), 1304 (w), 1188 (w), 1088 (m), 1072 (w), 1002 (w), 979 (m), 862 (m), 799 (w), 740 (m), 737 (m), 691 (s), 658 (m).

EXAMPLE 6: Dichloro[(N-(2-(diphenylphosphino)benzylidene)-2-(ethylthio)ethanamine) (triphenyl-phosphine)]-ruthenium(II) 6

(38) ##STR00021##

(39) Under argon a solution of 2-(ethylthio)ethanamine (0.36 g, 3.44 mmol) in THF (3 ml) is added to a solution of 2-(diphenylphosphino)benzaldehyde (1.00 g, 3.44 mmol) in THF (10 ml). After stirring for 12 h at 72 C. the reaction mixture is cooled to 0 C., DCM (3 ml) is added and the solvents are evaporated under vacuo. SNP-ligand N-(2-(diphenylphosphino)benzylidene)-2-(ethylthio)ethan-amine is obtained as an orange solid (1.20 g, 92%). Analytical data:

(40) ##STR00022##

(41) .sup.1H-NMR (400 MHz, CDCl.sub.3): 8.92 (d, J=4.80, 1H), 8.00 (m, 1H), 7.41 (m, 1H), 7.38-7.28 (m, 11H), 6.91 (m, 1H), 3.70 (dt, J=1.26, 7.07, 2H), 2.62 (t, J=7.33, 2H), 2.50 (q, J=7.33, 2H), 1.23 (t, J=7.33, 3H). .sup.13C-NMR (400 MHz, CDCl.sub.3): 161.12, 139.67, 137.93, 136.96, 136.87, 134.42, 133.77, 130.74, 129.28, 129.01, 128.13, 61.64, 32.56, 26.49, 15.28. .sup.31P-NMR (500 MHz, CDCl.sub.3): 13.55 (s, 1P). GC/MS: 377 (6%, M.sup.+), 348 (54%, [M29].sup.+), 288 (100%), 226 (20%), 208 (14%), 183 (28%), 165 (14%), 107 (11%), 89 (34%), 61 (14%).

(42) Under argon dichlorotris(triphenylphosphine)ruthenium(II) (1.52 g, 1.58 mmol) is added to a solution of N-(2-(diphenylphosphino)benzylidene)-2-(ethylthio)ethanamine (0.60 g, 1.58 mmol) in toluene (13 ml). After stirring for 19 h at 110 C. the reaction mixture is cooled to room temperature and evaporated under vacuo to a volume of 5 ml. To this red suspension DCM (20 ml) is added. After stirring for 15 min the suspension is filtered and dried under vacuo. Complex 6 is obtained as a red solid (0.88 g, 69%). Analytical data:

(43) .sup.1H-NMR (400 MHz, CDCl.sub.3): 8.80 (d, J=8.84, 1H), 7.56-6.81 (m, 29H), 6.35 (m, 2H), 4.60 (m, 1H), 4.20 (m, 1H), 3.03 (m, 2H), 2.29 (m, 1H), 0.92 (t, J=7.33, 3H). .sup.31P-NMR (500 MHz, CDCl.sub.3): 45.68 (d, J=30.23, 1P), 29.60 (d, J=30.23, 1P). MS (ESI): 811.10 (40%, M.sup.+), 776.12 (100%, [MCl].sup.+). Anal. calcd. for C.sub.41H.sub.39Cl.sub.2NP.sub.2RuS: C, 60.66%; H, 4.84%; N, 1.73%. Found: C, 60.85%; H, 4.90%; N, 1.64%.

EXAMPLE 7: Dichloro[(N-(2-(diphenylphosphino)benzyl)-2-(ethylthio)ethanamine)(triphenyl-phosphine)]ruthenium(II) 7

(44) ##STR00023##

(45) Under argon NaBH.sub.4 (0.18 g, 4.75 mmol) is added to a solution of N-(2-(diphenylphosphino)-benzylidene)-2-(ethylthio)ethanamine (0.60 g, 1.58 mmol) in ethanol (6 ml). After stirring for 18 h at 78 C. the reaction mixture is cooled to room temperature and water (18 ml) is added, followed by saturated aqueous NH.sub.4Cl. The phases were separated and the aqueous phase is extracted with DCM (310 ml). The combined organic phases are dried over MgSO.sub.4, filtered and concentrated under vacuo. SNP-ligand N-(2-(diphenylphosphino)benzyl)-2-(ethylthio)ethanamine is obtained as an orange liquid (0.53 g, 88%). Analytical data:

(46) ##STR00024##

(47) .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.63 (m, 1H), 7.50 (m, 1H), 7.37-7.26 (m, 10H), 7.19 (dt, J=1.26, 7.58, 1H), 6.91 (m, 1H), 4.03 (d, J=1.77, 2H), 2.73 (t, J=6.82, 2H), 2.53 (t, J=6.57, 2H), 2.48 (q, J=7.33, 2H), 1.23 (t, J=7.33, 3H). .sup.13C-NMR (400 MHz, CDCl.sub.3): 137.07, 136.21, 134.36, 134.14, 132.37, 129.55, 129.43, 129.15, 128.97, 127.78. .sup.31P-NMR (500 MHz, CDCl.sub.3): 16.06 (s, 1P). MS (EI): 379.4 (2%, M.sup.+), 318.3 (100%, [M61.1].sup.+), 304.3 (15%, [M75.1].sup.+), 275.2 (42%, [M104.2].sup.+).

(48) Under argon dichlorotris(triphenylphosphine)ruthenium(II) (1.22 g, 1.27 mmol) is added to a solution of N-(2-(diphenylphosphino)benzyl)-2-(ethylthio)ethanamine (0.48 g, 1.27 mmol) in toluene (17 ml). After stirring for 18 h at 110 C. the reaction mixture is cooled to room temperature and evaporated under vacuo to a volume of 5 ml. To this red suspension diethyl ether (15 ml) is added. After stirring for 15 min the suspension is filtered and dried under vacuo. Complex 7 is obtained as a red solid (0.39 g, 38%). Analytical data:

(49) .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.73-7.15 (m, 22H), 6.89 (m, 4H), 6.63 (m, 1H), 6.08 (m, 2H), 4.49 (m, 1H), 4.06 (m, 1H), 3.59 (m, 1H), 3.44 (m, 1H), 3.08 (m, 3H), 2.23 (m, 1H), 1.72 (m, 1H), 0.86 (t, J=7.33, 3H). .sup.31P-NMR (500 MHz, CDCl.sub.3): 35.94 (d, J=75.78, 1P), 34.74 (d, J=76.05, 1P). MS (ESI): 813.11 (34%, M.sup.+), 778.14 (100%, [MCl].sup.+). Anal. calcd. for C.sub.41H.sub.41Cl.sub.2NP.sub.2RuS: C, 60.44%; H, 5.26%; N, 1.72%. Found: C, 60.48%; H, 4.93%; N, 1.59%.

EXAMPLE 8: Dichloro[(N-(2-(diphenylphosphino)benzyl)-2-(ethylthio)ethanamine)(triphenyl-phosphine)]ruthenium(II) 8

(50) ##STR00025##

(51) Under argon 2-(methylthio)benzaldehyde (0.33 g, 2.18 mmol) is added to a solution of 2-(di-phenylphosphino)ethanamine (0.50 g, 2.18 mmol) in methanol (6 ml). After stirring for 42 h at 75 C. the reaction mixture is cooled to room temperature and evaporated under vacuo. SNP-ligand 2-(diphenylphosphino)-N-(2-(methylthio)benzylidene)ethanamine is obtained as a light-brown solid (0.66 g, 84%). Analytical data:

(52) ##STR00026##

(53) .sup.1H-NMR (500 MHz, CDCl.sub.3): 8.74 (s, 1H), 7.79 (dd, J=1.58, 7.88, 1H), 7.52-7.48 (m, 4H), 7.39-7.32 (m, 8H), 7.21 (m, 1H), 3.80 (m, 2H), 2.53 (m, 2H), 2.48 (s, 3H). .sup.13C-NMR (500 MHz, CDCl.sub.3): 159.37, 138.34, 134.24, 132.88, 132.74, 130.78, 130.66, 128.59, 128.49, 128.44, 128.25, 127.28, 125.50, 58.58, 29.99, 16.90. .sup.31P-NMR (500 MHz, CDCl.sub.3): 19.04 (s, 1P). GC/MS: 363 (2%, M), 348 (2%, [M15].sup.+), 320 (100%, [M43].sup.+), 288 (10%), 214 (12%), 183 (39%), 121 (20%), 108 (42%).

(54) Under argon dichlorotris(triphenylphosphine)ruthenium(II) (0.53 g, 0.55 mmol) is added to a solution of 2-(diphenylphosphino)-N-(2-(methylthio)benzylidene)ethanamine (0.20 g, 0.55 mmol) in toluene (15 ml). After stirring for 20 h at 110 C. the reaction mixture is cooled to room temperature and evaporated under vacuo to a volume of 5 ml. To this red suspension hexane (20 ml) is added. After stirring for 15 min the suspension is filtered and washed with hexane (4 ml). The red filter cake is dried under vacuo for 19 h and then suspended in diethyl ether (6 ml). The suspension is filtered, washed with diethyl ether (44 ml) and the filter cake is dried under vacuo. Complex 8 is obtained as a light-red solid (0.29 g, 67%). Analytical data:

(55) .sup.1H-NMR (400 MHz, CDCl.sub.3): 8.78 (d, J=8.84, 1H), 8.33 (m, 1H), 7.70 (m, 3H), 7.54-7.06 (m, 25H), 4.59 (m, 1H), 4.53 (m, 1H), 2.55 (m, 2H), 1.83 (d, J=2.53, 3H). .sup.31P-NMR (500 MHz, CDCl.sub.3): 40.62 (d, J=32.27, 1P), 36.72 (d, J=32.37, 1P). MS (ESI): 797.18 (62%, M), 762.12 (100%, [MCl].sup.+).

EXAMPLE 9: Dichloro[2-(diphenylphosphino)-N-(2-(methylthio)benzyl)ethanamine]-ruthenium(II) 9

(56) ##STR00027##

(57) Under argon NaBH.sub.4 (0.13 g, 3.47 mmol) is added to a solution of 2-(diphenylphosphino)-N-(2-(methylthio)benzylidene)ethanamine (0.42 g, 1.16 mmol) in ethanol (7 ml). After stirring for 20 h at 80 C. the reaction mixture is cooled to room temperature and DCM (10 ml) is added, followed by saturated aqueous NH.sub.4Cl-solution. The phases were separated and the organic phase is washed twice with water and once with brine. The organic phase is dried over MgSO.sub.4, filtered and concentrated under vacuo. Ligand 2-(diphenylphosphino)-N-(2-(methylthio)benzyl)ethanamine is obtained as a yellow liquid (0.36 g, 86%). Analytical data:

(58) ##STR00028##

(59) 10 .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.76 (m, 1H), 7.44 (m, 4H), 7.34 (m, 6H), 7.24 (m, 2H), 7.12 (m, 1H), 3.86 (s, 2H), 2.81 (m, 2H), 2.49 (s, 3H), 2.34 (m, 2H), 1.75 (bs, 1H). .sup.13C-NMR (400 MHz, CDCl.sub.3): 138.89, 138.25, 137.70, 133.13, 129.29, 128.95, 128.82, 128.05, 126.09, 125.31, 51.88, 46.43, 29.48, 16.17. .sup.31P-NMR (500 MHz, CDCl.sub.3): 20.60 (s, 1P). GC/MS: 350 (16%, [M15].sup.+), 318 (40%), 200 (26%), 183 (32%), 166 (11%), 152 (19%), 137 (100%), 121 (33%), 108 (36%), 91 (25%), 77 (13%), 45 (28%).

(60) Under argon dichlorotris(triphenylphosphine)ruthenium(II) (0.94 g, 0.99 mmol) is added to a solution of 2-(diphenylphosphino)-N-(2-(methylthio)benzyl)ethanamine (0.36 g, 0.99 mmol) in toluene (20 ml). After stirring for 19 h at 110 C. the reaction mixture is cooled to room temperature and evaporated under vacuo to a volume of 5 ml. To this suspension hexane (20 ml) is added. After stirring for 15 min the suspension is filtered and washed with hexane (4 ml) and diethyl ether (24 ml). The light-brown filter cake is dried under vacuo for 19 h and then suspended in diethyl ether (5 ml). After stirring for 15 min the suspension is filtered, washed with diethyl ether (31 ml) and the filter cake is dried under vacuo. Complex 9 is obtained as a light-brown solid (0.76 g, 96%). Analytical data:

(61) .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.80 (m, 6H), 7.69 (m, 1H), 7.47 (m, 3H), 7.31-7.01 (m, 17H), 6.88 (dt, J=2.02, 7.58, 1H), 7.18 (d, J=7.33, 1H), 5.48 (bs, 1H), 5.23 (d, J=12.63, 1H), 4.11 (m, 1H), 3.89 (m, 1H), 3.00 (m, 1H), 2.07 (m, 1H), 1.12 (m, 1H), 1.08 (s, 3H). .sup.31P-NMR (500 MHz, CDCl.sub.3): 49.83 (d, J=27.74, 1P), 37.96 (d, J=27.74, 1P). Anal. calcd. for C.sub.40H.sub.39Cl.sub.2NP.sub.2RuS: C, 60.07%; H, 4.92%; N, 1.75%. Found: C, 60.36%; H, 4.79%; N, 1.47%.

EXAMPLE 10: RuCl2(2-(diphenylphosphino)-N-(2-(n-butoxy)ethyl)ethanamine)PPh3 10

(62) ##STR00029##

(63) Under nitrogen, stirring and cooling NaH 60% in mineral oil (6.5 g, 162 mmol) is added portionwise to butanol (10 g, 135 mmol) in dry THF (70 ml) within 30 min. After 1 h at r.t. 2-bromo-1,1-dimethoxyethane (23.5 g, 135 mmol) in THF (20 ml) is added dropwise under slight cooling. The mixture is heated 44 h at reflux (67 C.) and (after complete conversion) cooled to r.t. and poured upon water (200 ml). Extraction with dichloromethane (2200 ml), washing of the combined organic layers with water (200 ml), drying over MgSO.sub.4, filtration and evaporation of the solvent gives 15.6 g (71%) of 1-(2,2-dimethoxyethoxy)butane as colorless liquid containing some (15%) n-butanol. Analytical data:

(64) ##STR00030##

(65) .sup.1H-NMR (400 MHz, CDCl.sub.3): 4.5 (t, 1H), 3.45-4.5 (2 m, 4H), 3.4 (s, 6H), 1.5-1.6 (m, 2 H), 1.4 (m, 2 H), 0.9 (t, 3 H) ppm. .sup.13C-NMR (400 MHz, CDCl.sub.3): 102.7 (d), 71.5 (t, OCH.sub.2), 70.4 (t, OCH.sub.2), 53.8 (q, OMe), 32.6 (t), 19.2 (t), 13.8 (q) ppm. GCMS: 131 (0.5%, [MOMe].sup.+), 75 (100%, [n-Butyl-OCH.sub.2].sup.+), 57 (8%, [n-Butyl].sup.+), 45 (28%).

(66) pTSA monohydrate (8.8 g, 46 mmol) dissolved in water (70 ml) is added to 1-(2,2-dimethoxyethoxy)-butane (5 g, 31 mmol) in DCM (50 ml). The mixture is stirred 46 h at 45 C. After phase separation and extraction of the water phase with DCM (50 ml), the combined organic layers are washed with conc. NaCO.sub.3 (25 ml) and conc. NaCl (225 ml), dried over MgSO.sub.4, filtered and evaporated at 500 mbar/40 C. The residue (3.25) is treated with butylhydroxytoluene (20 mg) and is bulb-to-bulb-distilled at 80-100 C./50 mbar to give 0.9 g (24%) of 2-butoxyacetaldehyde with 80% purity. The analytical data of this fraction was identical with the ones reported reported for this compound in H. C. Arndt, S. A. Caroll, Synthesis, 202, 1979 and the compound was used immediately in the next step. 2-Butoxyacetaldehyde (0.53 g, 4.56 mmol) in 1,2-dichloroethane (50 ml) is added to 2-(diphenylphosphino)-ethanamine (1.92 g, 8.0 mmol) under nitrogen and stirring. After addition of NaBH(OAc).sub.3 (1.5 g, 6.6 mmol) and 22 h stirring at r.t. the mixture is poured upon conc. NaHCO.sub.3 (100 ml), the phases are separated and the water-phase extracted with 1,2-dichloroethane (50 ml). The organic layers are washed with conc. aqueous NaCl (50 ml). The aqueous layers are re-extracted with 1,2-dichloroethane (100 ml). The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 1.25 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. Evaporation of the solvent gives SNP-ligand 2-butoxy-N-(2-(diphenylphosphino)ethyl)ethanamine (0.5 g, 37%). Analytical data:

(67) ##STR00031##

(68) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.45 (4 H, Ar), 7.3 (6 H, Ar), 3.5 (t, 2 H), 3.4 (t, 2 H), 2.7 2.8 (4 H), 2.3 (m, 2 H), 1.6-1.7 (br, 1 H, NH), 1.5-1.6 (m, 2 H), 1.3-1.4 (m, 2 H), 0.9 (t, 3 H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.5 and 138.4 (s), 132.8 and 132.6 (d), 128.6 (d), 128.5 and 128.4 (d), 71.0 (t), 70.0 (t), 49.2 (t), 46.8 and 46.6 (t), 31.8 (t), 29.15 and 29.0 (t), 19.3 (t), 13.95 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.4 ppm. GSMS (EI) (m/z): 328 ([MH].sup.+, 1%), 286 (1%), 272 (2%), 257 (9%), 255 (12%), 242 (33%), 229 (14%), 227 (32%), 201 (28%), 200 (71%), 199 (51%), 186 (60%), 185 (93%), 184 (11%), 183 (100%), 152 (12%), 130 (12%), 121 (33%), 109 (12%), 108 (43%), 107 (24%), 91 (18%), 74 (15%), 58 (88%), 57 (44%), 56 (52%), 41 (43%), 29 (28%).

(69) ONP-ligand 2-(diphenylphosphino)-N-(2-(n-butoxy)ethyl)ethanamine (0.5 g, 1.5 mmol) and RuCl.sub.2(PPh.sub.3).sub.3(1.05 g, 1.1 mmol) in dichloromethane (30 ml) are heated under reflux, stirring and nitrogen for 8 h. At room temperature hexane (150 ml) are added to the brown solution. The dark red precipitate is filtered, washed with hexane (320 ml) and dried under reduced pressure to give complex 10 (0.65 g, 56%) as a dark red powder. Analytical data of complex 10:

(70) .sup.1H-NMR (400 MHz, CD.sub.2Cl.sub.2): 7.4-7.5 (5 H), 7.0-7.3 (20 H), 5.1-5.2 (1 H), 4.0-4.1 (1 H), 3.9 (1 H), 3.2-3.6 (4 H), 2.6-2.9 (3 H), 1.55 (1H), 1.2-1.4 (3 H), 0.75-0.9 (2 H), 0.7 (3 H), 0.0 (3H). .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 61.0 and 60.8 (d), 45.9 and 45.7 (d). MS (ESI(+), m/z, %): 728 ([MCl].sup.+, 100%, identical with calculated isotope cluster). IR (ATR): 3162 (w), 3059 (w), 3056 (w), 2946 (w), 2909 (w), 2866 (w), 1480 (w), 1432 (m), 1189 (w), 1091 (m), 1069 (w), 1019 (m), 921 (w), 833 (w), 806 (w), 739 (m), 691 (s), 655 (m), 618 (w). Anal. calcd. for C.sub.38H.sub.43Cl.sub.2NP.sub.2RuO: C, 59.77%; H, 5.68%; N, 1.83%. Found: C, 59.74%; H, 5.66%; N, 1.73%.

EXAMPLE 11: Catalytic hydrogenation of ethyl benzoate using RuCl2(2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)ethanamine)PPh3 1

(71) Catalyst 1 (1.5 mg, 2 mol) and ethyl benzoate (0.6 g, 4 mmol) are dissolved in toluene (10 ml) and placed in a 120 ml Premex autoclave under argon. After addition of sodium methylate (22 mg, 0.4 mmol) the argon atmosphere is replaced by hydrogen and the mixture is heated under stirring 16 h at 100 C. under 50 bar hydrogen. The pressure is released and the mixture treated at room temperature with 2% H.sub.3PO.sub.4 (30 ml). Extraction is carried out with t-butyl methyl ether (50 ml). GCMS-analysis reveals a quantitative conversion to benzyl alcohol with 99% purity.

EXAMPLE 12: Catalytic hydrogenation of Sclareolide with 0.05% RuCl2(2-(diphenylphosphino)-N-(thiophen-2-ylmethyl)ethanamine)PPh3 1

(72) Commercially available (+)-(3aR,5aS,9aS,9bR)-Sclareolide (CAS 564-20-5) was used as substrate.

(73) Catalyst 1 (1.5 mg, 2 mol) and Sclareolide (1 g, 4 mmol) are dissolved in toluene (10 ml) and placed in a 120 ml Premex autoclave under argon. After addition of sodium methylate (22 mg, 0.4 mmol) the argon atmosphere is replaced by hydrogen and the mixture is heated under stirring 16 h at 100 C. under 50 bar hydrogen. After work-up 1 g Sclareodiol (99.5%) is obtained with 100% purity according to GCMS and NMR analysis. The analytical data of (1R,2R,4aS,8aS)-Sclareodiol are consistent with the ones described for this compound (CAS 38419-75-9) in the literature, e.g. in J. H. George et al., Org. Lett. 14, 4710 (2012).

(74) In the following table some variations of this transformation are described:

(75) TABLE-US-00001 TABLE 1 General conditions as above (example 12). run Scale (a) catalyst Loading (b) Sclareolide (c) Sclareodiol Ambrox TON (d) 1 1 g/10 ml 1 0.05% ./. 100% ./. 2000 2 1 g/10 ml 1 0.01% 21% 75% 4% 8000 3 26 g/63 ml 2 0.01% 8% 88% 5% 9000 4 2 g/20 ml 3 0.05% ./. 100% ./. 2000 5 1 g/10 ml 3 50 ppm 14% 85% 1% 17000 6 26 g/63 ml 3 50 ppm 20% 67% 12% 16000 7 1 g/10 ml 4 0.01% 2% 98% ./. 9800 8 1 g/10 ml 4 25 ppm 3% 96% 1% 39000 9 1 g/10 ml 4 10 ppm 20% 77% 3% 80000 (a) Substrate/solvent scale. (b) Catalyst loading/substrate in mol % or mol-ppm. (c) Substrate Sclareolide (CAS 564-20-5). (d) Turnover numbers as deduced from the conversion detected in the crude product.

EXAMPLE 13: Catalytic Hydrogenation of Sclareolide with Ru(II)-Catalyst and Base KOMe in THF

(76) Catalyst 3 (1.9 mg, 2.6 mol) dissolved under ultrasound 5-10 min in THF (5 ml) is added under argon to Sclareolide (26 g, 104 mmol) in THF (58 ml) in a Premex autoclave. After addition of KOMe (0.72 g, 10.4 mmol) the argon atmosphere is replaced by hydrogen and the mixture is heated under stirring 22 h at 100 C. under 50 bar hydrogen. After cooling to r.t. pressure is released and the reaction mixture poured onto aqueous 2% H.sub.3PO.sub.4 under stirring. Extraction with tert-butylmethylether (250 ml), washing of the combined organic layers with water (50 ml), drying over MgSO.sub.4, filtration and evaporation of the solvents gives 26.4 g of a white solid, consisting of Sclareodiol (94%), Ambrox (2%) and Sclareolide (3%) according to GC and NMR.

(77) In the following table some variations of this transformation are described:

(78) TABLE-US-00002 TABLE 2 General conditions as above (example 13). run Scale (a) catalyst loading (b) Sclareolide (c) Sclareodiol Ambrox TON (d) 1 26 g/63 ml 3 50 ppm ./. 98% 1 19800 2 26 g/63 ml 3 25 ppm 3% 94% 3% 39000 3.sup.e 26 g/63 ml 4 25 ppm 1.5% 97% 1.5% 39400 4 250 g/630 ml 4 25 ppm ./. 95% 5% 40000 5 26 g/63 ml 5 0.01% ./. 99% 1% 10000 6 26 g/63 ml 5 25 ppm 4% 92% 3% 38000 7 26 g/63 ml 10 0.1% 66% 29% 4% 290 8 26 g/63 ml 10 0.01% 96% 2% ./. 200 (a) Substrate/solvent scale. (b) Catalyst loading/substrate in mol %. (c) Substrate Sclareolide (CAS 564-20-5). (d) Turnover numbers as deduced from the conversion detected in the crude product. .sup.e4 mol % KOMe instead of 10 mol %.

EXAMPLE 14: Catalytic Hydrogenation of Sclareolide with Ru(II)-Catalyst 4 and Bases NaH or KH

(79) Catalyst 4 (2 mg, 2.6 mol) dissolved under ultrasound 5-10 min in toluene (20 ml) is added under argon to Sclareolide (26 g, 104 mmol) in toluene (43 ml) in a Premex autoclave. After addition of potassium hydride 35% in paraffine oil (1.2 g, 10.4 mmol) the argon atmosphere is replaced by hydrogen and the mixture is heated under stirring 7 h at 105 C. under 50 bar hydrogen. After cooling to r.t. pressure is released and the reaction mixture poured onto aqueous 2% H.sub.3PO.sub.4 (30 ml) under stirring. Extraction with tert-butylmethylether and ethyl acetate, drying over MgSO.sub.4, filtration and evaporation of the solvents gives 27.2 g of a white solid, consisting of Sclareodiol (94%), Ambrox (5%) and Sclareolide (1%) according to GC.

(80) The same procedure using sodium hydride 60% in paraffine oil and solvent THF under otherwise identical conditions and ratios gave 26.5 g of a white solid, consisting of Sclareodiol (95%), Ambrox (3%) and Sclareolide (2%) according to GC.

EXAMPLE 15: Catalytic Hydrogenation /-Unsaturated Ester 11

(81) ##STR00032##

(82) Commercially available (E)-ethyl 3-(4-isobutylphenyl)acrylate 11 (3 g, 12.4 mmol), catalyst 4 (9.7 mg, 12 mol) and KOMe (92 mg, 1.24 mmol) in THF (30 ml) are hydrogenated 16 h in a Parr-autoclave at 105 C. under hydrogen (50 bar) and stirring. After cooling to r.t. pressure is released and the reaction mixture poured onto aqueous 2% H.sub.3PO.sub.4 (10 ml) under stirring. After extraction with tert-butylmethylether(20 ml) the organic layers are washed with brine (20 ml). Drying over MgSO.sub.4, filtration and evaporation of the solvents and bulb-to-bulb distillation at 120-140 C./0.05 mbar gives 2.6 g (91%) of 3-(4-isobutylphenyl)propan-1-ol 12 as a colorless oil and a GC-purity of 97-100%. Analytical data:

(83) 15 .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.0-7.1 (4 H), 3.6 (t, 2 H), 2.65 (t, 2 H), 2.4 (d, 2 H), 1.85-1.9 (3 H), 1.7 (br, OH, 1 H), 0.9 (d, 6 H) ppm. .sup.13C-NMR (400 MHz, CDCl.sub.3): 139.2 (s), 139.0 (s), 129.2 (d), 128.1 (d), 62.4 (t), 45.1 (t), 34.3 (t), 31.7 (t), 30.3 (d), 22.4 (q) ppm. GCMS: 192 (27%, [M].sup.+), 174 (4%, [MH.sub.2O].sup.+), 149 (83%), 132 (14%), 131 (100%), 117 (24%), 116 (12%), 115 (15%), 105 (26%), 104 (12%), 91 (32%). IR (film): 3326 (br), 3009 (w), 2951 (s), 2925 (m), 2867 (m), 1512 (m), 1465 (m), 1418 (m), 1383 (m), 1366 (m), 1166 (w), 1116 (w), 1058 (m), 1039 (s), 1021 (w), 915 (w), 846 (m), 810 (w), 791 (m), 695 (s).

(84) The same reaction with 0.01% catalyst 4 (1 mg, 1.24 mol) under otherwise identical conditions gave saturated ester 15 (2.91 g) as a yellow oil containing 82% saturated ester and 18% 3-(4-isobutylphenyl)propan-1-ol 12. Analytical data of 15:

(85) ##STR00033##

(86) .sup.1H-NMR (400 MHz, CDCl.sub.3): 7.0-7.1 (4 H), 4.2 (q, 1 H), 2.9 (t, 2 H), 2.6 (t, 2 H), 2.4 (d, 2 H), 1.8-1.9 (1 H), 1.2 (t, 3 H), 0.9 (d, 6 H) ppm. .sup.13C-NMR (400 MHz, CDCl.sub.3): 173.1 (s, CO), 139.6 (s), 137.8 (s), 129.2 (d), 128.0 (d), 60.4 (t), 45.0 (t), 36.1 (t), 30.25 (t), 30.24 (d), 22.4 (2 C, q), 14.2 (q) ppm. GCMS: 234 (10%, [M].sup.+), 191 (26%), 160 (33%), 147 (11%), 118 (18%), 117 (100%), 104 (14%), 91 (12%).

EXAMPLE 16: Catalytic Hydrogenation of Unsaturated Ester 13

(87) ##STR00034##

(88) For the synthesis of methyl dodec-9-enoate 13 see for example K. Takai, Organic Reactions 64, pages 253, 488 (2004).

(89) A mixture of methyl dodec-9-enoate 13 E/Z 84:16 (30 g, 141 mmol), KOMe (1.05 g, 14.11 mmol) and catalyst 4 (11 mg, 14 mol) is hydrogenated (50 bar) at 80 C. and under stirring for 21 h. After cooling to r.t. pressure is released and the reaction mixture poured onto aqueous 2% H.sub.3PO.sub.4 (30 ml) under stirring. After extraction with tert-butylmethylether the organic layers are washed with brine (20 ml). Drying over MgSO.sub.4, filtration and evaporation of the solvents gives 27 g of a yellowish oil which is purified by distillation at 62-72 C./0.05 mbar giving 21.5 g (83%, corr) of dodec-9-en-1-ol 14 with 93-98% purity and an E/Z ratio of 85/15. The analytical data of the isomers are identical with the ones from the literature (H. J. Bestmann et al., Chem. Ber. 113, 1115, 1980, and references therein).

EXAMPLE 17: slightly modified procedure for the synthesis of catalyst RuCl2(2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine)PPh3 3 with correct elemental analysis

(90) ##STR00035##

(91) Methylthioethanal was prepared as described in Synthesis 7, 659 (1987) from (2,2-dimethoxyethyl)(methyl)sulfane.

(92) Under nitrogen and stirring NaBH(OAc).sub.3 (2.85 g, 12.75 mmol) is added to 2-(diphenylphosphino)-ethanamine (1.92 g, 8.0 mmol) and methylthioethanal (0.82 g, 8.75 mmol) in 1,2-dichloroethane (50 ml). After 22 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 (50 ml) and extracted with 1,2-dichloroethane (50 ml). The organic layers are washed with conc. aqueous NaCl (50 ml). The aqueous combined aqueous layers are re-extracted with 1,2-dichloroethane. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 2.83 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. Evaporation of the solvent gives SNP-ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)-ethanamine (1.2 g, 45%). Analytical data:

(93) ##STR00036##

(94) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.45 (4 H, Ar), 7.3-7.35 (6 H, Ar), 2.7-2.8 (4 H), 2.5 2.6 (m, 2 H), 2.2-2.3 (m, 2 H), 2.05 (3 H), 1.7 (br, 1 H, NH) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.8 (s), 132.7 (d), 128.4-128.8 (2 d), 47.8 (t), 46.3 and 46.1 (t), 34.4 (t), 29.1 and 28.9 (t), 15.1 (q, SMe) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.7 ppm. GSMS (EI) (%) (m/z): 288 ([MCH.sub.3].sup.+, 8%), 256 ([M+OMeSH].sup.+, 80%), 242 (8%), 199 (19%), 185 (100%), 183 (89%), 152 (11%), 121 (27%), 108 (20%), 107 (21%), 91 (11%), 75 (43%), 61 (14%).

(95) SNP-Ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine (0.5 g, 1.65 mmol) and RuCl.sub.2(PPh.sub.3).sub.3 (1.15 g, 1.15 mmol) in dichloromethane (30 ml) are heated under reflux, stirring and nitrogen for 22 h. At room temperature hexane (150 ml) is slowly added to the organge suspension under stirring. The precipitate is filtered, washed with hexane (20 ml) and dried under high vacuum to give complex 3 (0.79 g, 93%) as an orange solid. Analytical data:

(96) .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 46.1 and 44.7 (2 d, 30.5 Hz, major isomer), 46.6 and 44.4 (2 d, 32.5 Hz, minor isomer). MS (EI in MeOH, HCO.sub.2H, %, m/z): 742 (100%), 702 ([MCl].sup.+, 82%). IR (ATR): 3162 (w), 3047 (w), 2914 (w), 2857 (w), 1480 (w), 1454 (w), 1431 (m), 1299 (w), 1184 (w), 1086 (m), 1012 (w), 979 (w), 958 (w), 864 (w), 801 (w), 740 (m), 691 (s), 658 (m), 619 (w). Anal. calcd. for C.sub.35H.sub.37Cl.sub.2NP.sub.2RuS: C, 56.99%; H, 5.06%; N, 1.9%. Found: C, 56.81%; H, 5.20%; N, 1.98%.

EXAMPLE 18: slightly modified procedure for the synthesis of catalyst RuCl2(2-(diphenylphosphino)-N-(2-(n-butylthio)ethyl)ethanamine)PPh3 4 with correct elemental analysis

(97) ##STR00037##

(98) For the synthesis of n-butylthioethanal see N. A. Keiko et al. Arkivoc 127-138 (2011).

(99) Under nitrogen and stirring NaBH(OAc).sub.3 (3 g, 13.3 mmol) is added to 2-(diphenylphosphino)-ethanamine (2 g, 8.3 mmol) and n-butyllthioethanal (1.2 g, 9.1 mmol) in 1,2-dichloroethane (50 ml). After 22 h stirring at room temperature the mixture is poured upon conc. NaHCO.sub.3 and is extracted with DCE. The organic layers are washed with conc. aqueous NaCl. The aqueous phase is re-extracted with DCE. The combined organic layers are dried over MgSO.sub.4, filtered and evaporated to give 3.15 g of a yellowish oil which is taken up in ethyl acetate and purified by flash chromatography over silica gel using eluent ethyl acetate. In a first fraction by product 2-(butylthio)-N-(2-(butylthio)ethyl)-N-(2-(diphenylphosphino)ethyl)ethanamine (0.72 g, 19%, after solvent evaporation) is separated. Analytical data:

(100) ##STR00038##

(101) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4 (4 H, Ar), 7.3 (6 H, Ar), 2.7-2.6 (6 H), 2.45-2.55 (8 H), 2.2 (2 H), 1.5-1.6 (4 H), 1.35-1.45 (4 H), 0.9 (t, 6 H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.8 (s), 132.65 (d), 130.55 (d), 128.55 (d), 53.9 (t), 50.2 (t), 32.0 (t), 29.8 (t), 25.7 (t), 22.0 (t), 13.5 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.0 ppm. MS (EI) (m/z): 404 ([MC4H9].sup.+), 373 (23%), 372 (90%), 358 (100%), 288 (6%), 256 (8%), 186 (9%), 185 (61%), 183 (25%), 117 (55%), 61 (16%). 57 (11%). IR (film): 3052 (w), 2954 (m), 2926 (m), 2870 (m), 1738 (w), 1586 (w), 1480 (w), 1457 (m), 1434 (m), 1377 (w), 1294 (w), 1192 (m), 1095 (m), 1069 (w), 1026 (w), 998 (w), 914 (w), 737 (m), 695 (s).

(102) Evaporation of the solvent from the second fraction gives SNP-ligand 2-(diphenylphosphino)-N-(2-(methylthio)ethyl)ethanamine (0.77 g, 27%). Analytical data:

(103) ##STR00039##

(104) .sup.1H-NMR (CD.sub.2Cl.sub.2, 400 MHz): 7.4-7.45 (4 H, Ar), 7.3-7.35 (6 H, Ar), 2.7 (4 H), 2.6 (m, 2 H), 2.5 (2 H), 2.3 (m, 2 H), 1.6 (br, 1 H, NH), 1.5 (m, 2 H), 1.4 (m, 2 H), 0.9 (t, 3 H) ppm. .sup.13C-NMR (CD.sub.2Cl.sub.2, 400 MHz): 138.85 (s), 132.65 (d), 130.55 (d), 128.45 (d), 48.5 (t), 46.2 (t), 32.3 (t), 31.9 (t), 31.6 (t), 28.95 (t), 22.0 (t), 13.5 (q, Me) ppm. .sup.31P-NMR (CD.sub.2Cl.sub.2, 200 MHz): 20.7 ppm. MS (EI) (m/z): 346 ([M+H].sup.+, 289 (10%), 288 (55%), 257 (18%), 256 ([M+OBuSH].sup.+, 100%), 242 (20%), 199 (13%), 186 (18%), 185 (87%), 183 (31%), 69 (20%). IR (film): 3051 (w), 2926 (m), 2871 (w), 1953 (w), 1886 (w), 1812 (w), 1737 (w), 1671 (w), 1585 (w), 1479 (w), 1456 (m), 1433 (m), 1376 (w), 1331 (w), 1272 (w), 1240 (w), 1184 (w), 1117 (m), 1068 (w), 998 (w), 737 (m), 694 (s).

(105) SNP-ligand 2-(diphenylphosphino)-N-(2-(n-butylthio)ethyl)ethanamine (0.25 g, 0.7 mmol) and RuCl.sub.2(PPh.sub.3).sub.3 (0.5 g, 0.5 mmol) in dichloromethane (15 ml) are heated under reflux, stirring and nitrogen for 24 h. At room temperature hexane (100 ml) are added. The precipitate is filtered, washed with hexane (320 ml) and dried under reduced pressure to give complex 4 (0.35 g, 88%) as an orange powder. Analytical data:

(106) .sup.1H-NMR (400 MHz, CD.sub.2Cl.sub.2): 6.9-7.4 (25 H), 4.5 and 4.7 (1 H), 2.3-3.7 (9 H), 1.55 (2H), 1.0-1.5 (4 H), 0.8 (t, 3H). .sup.31P-NMR (CD.sub.2Cl.sub.2, 400 MHz): 45.6 and 45.9 (2 d), 44.7 and 44.8 (2 d). MS (ESI(+) in MeOH, HCO.sub.2H, %, m/z): 754 ([MClHCl+HCO.sub.2H].sup.+, 100%, identical with calculated isotope cluster), 744 ([MCl].sup.+, 100%). IR (ATR): 3162 (w), 3059 (w), 2947 (w), 2859 (w), 1585 (w), 1480 (w), 1454 (w), 1432 (m), 1303 (w), 1267 (w), 1187 (w), 1156 (w), 1138 (w), 1088 (m), 1067 (w), 1027 (w), 1006 (w), 983 (m), 914 (w), 865 (w), 799 (w), 751 (w), 740 (m), 737 (m), 691 (s), 657 (m), 619 (m). Anal. calcd. for C.sub.38H.sub.43Cl.sub.2NP.sub.2RuS: C, 58.53%; H, 5.56%; N, 1.80%. Found: C, 58.24%; H, 5.54%; N, 1.71%.