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Homogeneous catalysis in water Part II. Synthesis and characterization of ruthenium water-soluble complexes
Jownal of Molecular Catalysis, 72 (1992) M2849
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Homogeneous catalysis in water Part II. Synthesis and characterization of ruthenium water-soluble complexes E. Fache, C. Santini, F. Senocq and J. M. Basset* Institut de Recherches sur la Catalyse, 2 Au. A. Einstein, 69626 ViUeurbanne C&%x O+-amej Ecole Suptkieure de Chimie Industrielle de Lyon, 43 Bd du 11 Nov. 1918, 69100 Villeurbanne (France) (Received July 23, 1991; revised December 19, 1991)
Abstract Seven water-soluble complexes of ruthenium and TPPTS have been prepared and characterized (TPPTS is the trisodium salt of the trl(m-sulfophenyl)phosphine): 3, RuH~(TPPTS)~ 4, [RuCl,(TPPTS),], 1, RuHCl(TPPTS)e 2, RuH(OAc)(TPPS), RuHI(TPPTS)e 6, RuCl,(CO),(TPPTS), 6 and [Ru(OAc)(CO),(TPPTS)]~ 7. Spectroscopic investigations have shown that in solution they have the same structures as their organosoluble analogues containing the ligand PPh,.
Introduction Since the work of Chatt on water-soluble monosulfonated triphenylphosphine [ 1, 21, numerous water-soluble liiands have been prepared 131, and, among them, the t&odium salt of tri(m-sulfophenyl)phosphine (or TPPTS) [4]. This ligand, highly water-soluble, and very sparingly soluble in organic solvents, finds industrial use in the hydroformylation of propene by rhodium moieties [ 51. It also has been used to prepare complexes of rhodium, ruthenium, osmium, iridium and other Group VI, VII and X metals [6, 71. Due to the key role of ruthenium complexes in the hydrogenation of unsaturated substrates, it appeared interesting to prepare the water-soluble analogues of the ruthenium Bison-Osborn catalysts [8]. We present here seven new compounds of ruthenium with the TPPTS ligand: [RuC12(TPPTS),], (l), RuHCl(TPPTS)a (Z), RuH(OAc)(TPPTS), (3), RuH,(TPPTS), (4), RuHI(TPPTS), (S), RuCla(CO)a(TPPTf$. (6) and [RuWWW),W’P’Wl~ (7). Classical methods to prepare Will
0304-5102/92/$5.00
0 1992 - Elsevier Sequoia. All rights reserved
332
aration has been based on a ligand exchange in biphasic medium of the classical Wilkinson catalyst by TPPTS according to the general equation: R&(PPh,),
+ nTPPTS -
RI&(TPPTS),
+ nPPha
The other methods we used involved either direct carbonylation of 1 which leads to 6, addition of stoichiometric amount of TPPTS to [Ru(CO),(OAc)], which leads to 7 or exchange of halide (Cl for I) which has also been used to obtain 6 from 2.
Experimental
1 [RuCl~(TPPXS’J2: 0.542 g of RuCla(PPh& is dissolved in 60 cm3 of THF and heated to 60 “C. A solution of 0.733 g of TPPTS in 10 cm3 of water is then added dropwise, under vigourous stirring. The stirring and heating are maintained for 30 min. Separation occurs, giving a very pale orange organic solution and a deep red aqueous solution. After gentle cooling to room temperature, the aqueous phase is collected by decantation and argon is bubbled through it for a few minutes, in order to eliminate THF. The organic phase is discarded without investigation of its components. The aqueous solution is then evaporated to dryness, to give 0.540 g (73% yield) of a red-brown solid. 2 RuHCl(TppTs),: 0.46 g of RuHCl(PPh3)3 reacts with 1 g of TPPTS according to the same procedure as that followed for 1.Overall yield is 0.68 g (70%) of a deep red solid. 3 RuH~OAc)(TppTs),: 0.54 g of RuH(OAc)(PPh,), reacts with 1.05 g of TPPTS according to the same procedure as that followed for 1. Overall yield is 0.6 g (53%) of a bright yellow solid. 4 RuH~(TppTs),: 0.694 g of RuH2(PPh3), reacts with 1.46 g of TPPTS according to same procedure followed for 1. The overall yield is 1.26 g (80%) of a deep yellow solid. 5 RuHI(TPPZS], : 0.32 g of RIIHCI(TPPTS)~(2) is dissolved with stirring at room temperature in 10 cm3 of water to give a red solution. 0.2 g of Nal (&fold excess) is added and the solution becomes purple instantaneously. The stirring is maintained for 1 h. After evaporation to dryness in VUCUQ, the purple solid is washed several times with ethanol. The yield is 0.2 g (60%). 6 RuClz(CO)z(TppTs)2: 0.1 g of 1 is dissolved in 300 cm3 of 2-(2methoxyethoxy)ethanol and heated at 100 “C for 1 h with stirring and gentle bubbling of carbon monoxide. The solution becomes progressively brown, then colourless, and a small amount of a white precipitate appears, which is eliminated by 6ltration after cooling the solution to room temperature (IR spectra of this solid shows the presence of the trcms-tram-trans isomer of 6:
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7 [Ru&‘O), (OAC)(TPPZS’]~: 0.8 g of TPPTS is dissolved in 100 cm3 of methanol at 55 “C with vigourous stirring. After dissolution, 0.14 g of [Ru(CO),(OAc)], is added. The stirring and the temperature are maintained for 15 h. The solution becomes yellow. After cooling to room temperature, a yellow solid precipitates, which is isolated by Ilkration, washed with ethanol and dried in WCZULThe yield is 0.77 g (70%). The elemental analyses are in good agreement, which the proposed formulae, but indicate the presence of very small and variables amounts of sodium sulfate, depending on the sample of TPPTS used. The NMR spectra were recorded on a Bruker AC 100 for ‘H and 13C, and on a Varian XL 100 and a Bruker WM 250 for 31P. The spectra of the water-soluble compounds have been recorded in DzO, the others in CD2C12.
Results
and discussion
[RuC~&TPPTS)~]~(1) exhibits a 31P NMR spectrum with one singlet at 6= 56.6 ppm. This resonance is very close to that at 6= 56 ppm observed by Armitt et al. at + 20 “C for [RuCl,(PPh,),], [ 91.With 1, we were unable to reach a temperature sufficiently low to observe the splitting of the signal (AB pattern), as seen with the organosoluble complex. The ‘H NMR of 1 shows only the phenylic protons, as its 13C spectrum exhibits Cl at 136.4 ppm (tr, J(P-C)=22 Hz), Cz at 139.7 ppm (broad unresolved peak), C3 at 145.0 (d, J(P-C) =4 Hz), C4 at 133.5 ppm (&P-C)=0 Hz) and Cs and Cs as two broad peaks at 131.6 and 129.9 ppm (accurate attribution was not possible). In the same conditions, the 13C spectrum of free TPPTS gives Cl at 139.2 ppm (J(P-C)= 11 Hz), Cz at 139.1 ppm @(P-C)= 18 Hz), C3 at 145.7 ppm (&P-C) = 7 Hz), C4 at 129.3 ppm (J(P-C)=O Hz), C5 at 132.4 ppm (J(P-C)=6 Hz) and CB at 132.9 ppm (J(P-C)= 21 Hz). 1 does not react with an excess of TPPTS to give the tris phosphine complex RuCl,(TPPTS),, as occurs when [RuC12(PPh3)2]2is allowed to react with PPh,. This difference in behaviour is likely due to the very large cone angle of TPPTS (cu. 170” [ 7c] compared with 145” for PPh, [lo]), which prevents coordination of a third TPPTS ligand when two chlorine atoms are already on the ruthenium. Jn water and under Hz (1 atm), 1 gives a hydrido complex, as indicated by the appearance in the ‘H NMR spectrum of a triplet at - 15.4 ppm (&P-H) = 20 Hz) which thus could be attributed to a RuHX(‘T.PPTI& moiety. This species had not been characterized. RuHCl(TPPTS)3 (2) exhibits spectral data almost identical to those of RuHCl(PPh3)3. The ‘H NMR spectra shows, besides phenylic protons, one hydride signal (quadruplet, 6= - 18.5 ppm, J(P-H) = 25 Hz), while the 31P spectra gives a broad singlet at S= 57 ppm. These data are similar to those observed for RuHCl(PPh3)3. These two compounds probably have the same fluxional distorted trigonal bipyramid structure [ 11].2 reacts with molecular hydrogen in the presence of an excess of TPPTS to give RuH&‘PPTS),, as evidenced by ‘H and 31P NMR data (vide imu).
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RuH(OAc)(TPPTS)a (3) has spectral data similar to those of RuH(OAc)(PPh&. The 31P NMR gives an AaB pattern (&Pa)=46.4 ppm, 6(Pb) = 79.7 ppm, &P-P) = 29 Hz). The ‘H NMR shows the methyl protons of the acetato group at 1.69 ppm and the hydride as an asymmetric fourline signal centered at - 18.4 ppm (&P-H)= 26 Hz). The 13C NMR shows the methyl carbon of the acetato group at 6=25.5 ppm and the carboxylic carbon at 187.6 ppm. No coupling with phosphorus atoms is observed. The phenylic carbons appear between 129.6 ppm (C,, J(P-C)=O) and 145.2 ppm (C,, J(P-C) = 3 Hz), without any signillcant change from the spectrum of 1. Thesevalues are very close to those obtained for RuH(OAc)(PPh3)3: GP(Pa) = 43.8 ppm, GP(Pb) = 77.6 ppm, .&P-P) = 27.5 Hz; SH(Me) = 1.12 ppm, GH(Rr,+)= - 19.9 ppm, &P-H)=27 Hz; E(C-Me)=2x4 ppm, 6C(O-C-Me)= 180.8 ppm. These two compounds seem &hare the same octahedral geometry, with the three phosphorus atoms in equatorial position and the hydride in axial position [ 12 1. The spectral data of R~IzI~(TPPTS)~(4) are also similar to those of RuHz(PPh3),. At a concentration of 0.06 M, the 31P NMR gives an AzBz pattern: 6(Pa)=41.9 ppm, S(Pb)=53.9 ppm, J(P-P)=12.5 Hz (to be compared with &Pa) =46.8 ppm, S(Pb) -55.1 ppm, J(P-P)= 15 Hz obtained for H2Ru(PPh,),). The ‘H NMR in the hydride region gives a complicated signal with four intense merging lines centered at - 10.5 ppm, the apparent coupling constant being cu. 35 Hz (- 9.7 ppm and J(P-H) =40 Hz for H,Ru(PPh,),). At this concentration, a small amount of a second product is detected in the {1H}31PNMR spectrum as an AaB pattern @(Pa) = 46.5 ppm, 6(Pb) = 79.9 ppm, J(P-P) = 25 Hz) with few free TPPTS (&P) = - 5.5 ppm), and in the ‘H NMR as a small quartet at - 17.7 ppm (J(P-I-I) = cu. 25 Hz). The higher the dilution, the more important the second product and the free TPPTS are. Solvated species RuI-I,(PPh,),Q, L =pyridine [ 131, THF or cyclohexanone [ 141, with similar A,B pattern in the 31P NMR, have been observed. It is possible to propose that, in solution, we probably have the dissociation equilibrium: RuH&l’PPTS), + Ha0 =
RuHa(TPPTS),(HaO) + TPPTS
The second set of signals observed by NMR may be attributed to the solvated species RuH&l’PPTS)3(H,0). The ‘H NMR spectrum of RuHI(TPPTS)3 (6) shows one hydride signal at - 15.4 ppm (quadruplet, &P-C) = 25 Hz) and the 31P NMR spectrum a broad singlet at 59.5 ppm. Although, to our best knowledge, the organosoluble analogue RuHI(PPh,), is not known, we can assume that 6 has the same structure as 2, i.e. a fluxional distorted trigonal bipyramid. Because Da0 is the only deuterated solvent we can use with this family of water-soluble compounds, it was not possible to reach a temperature sufficiently low to observe the splitting of the NMR signals. The IR spectrum of RuCI,(CO)&~‘PPTS)~ (6) presents two v(C0) bands at 2062 and 1998 cm- ‘, indicative of two terminal carbonyl groups in cis configuration (2056 and 1991 cm-’ for RuCl,(CO),(PPh,),). The 31P NMR
335
spectrum shows one singlet at 20.7 ppm (17.4 ppm for RuCl,(CO),(PPh&,). The 13CNMR signal for CO (S= 193.6 ppm, J(P-C) -0) and for the phenylic carbons (129 to 146 ppm) are very close to those of RuC1,(C0)2(PPh,)2, (&CO) = 190 ppm). The water-soluble complex has therefore the same octahedral structure as its organosoluble analogue, with the phosphorous atoms in axial position and the two chlorine atoms in the equatorial plane with a cis configuration [ 151. With [Ru(OAC)(CO),(TPPTS)]~ (7), the 31P NMR spectrum exhibits one singlet at 16.7 ppm and the ‘H NMR gives the methyl of the acetato group as a singlet at 1.67 ppm. The 13C NMR exhibits the methyls of the acetato at 25.5 ppm, the acidic carbons at 191.5 ppm and the terminal carbonyls at 207 ppm. The NMR data for [Ru(OAc)(CO),(PPh,)], are similar: 6P = 13.7 ppm, GH(Me) = 1.15 ppm, GC(Me)=23.5 ppm, X(0-_C-Me)= 186.5 ppm and GC(Ru-CO) = 206 ppm. The IR spectra of the two compounds are very close: they show four intense
It does not seem possible to prepare RuC~~(TPPTS)~,probably for steric reasons due to the large cone angle of TPPTS as compared to that of PPhs [ 7~1. All the other ruthenium complexes that we have been able to synthesize have organosoluble analogues and seem to adopt the same geometrical conflgumtion in water. This similarity of structure is deduced from a systematic similarity in spectroscopic data (IR, 31P, ‘H and 13C NMR). Therefore, one may conclude that the main differences in coordinating properties between TPPTS and PPh3 are steric and not electronic. In the following paper of this series, we will consider the differences and analogies in the catalytic reactivity of the two families of complexes. References 1 S. Arland, J. Chat%, N. R. Davis and A. Williams, J. Chem. Sot., (1958) 276. 2 A. F. Borowski, D. J. Cole-Hamilton and G. W-on, Nom. J. Chim., 2 (1978) 137; F. Jo6, Z. T6th and M. T. Beck, Chim. Actu, 25 (1977) L61; F. Jo6 and Z. T6th, J. Mol. Cad., 8 (1980) 369; F. Jo6 and M. T. Beck, React. Kin&. CataL I.&t., 2 (1980) 257. 3 D. Sinou, B&L Sot. Chim. F’r., 3 (1987) 480. 4 Ger. Off&n., 2627354 (1976) to E. G. Kunta. 5 E. G. Kuntz, Chemtech, (1987) 570. 6 C. Larpent, R. Dabard and H. Patin, Inarg. Chenz, 26 (1987) 2922; A. Dedieu, P. Escaffre, J. M. Frances, Ph. Kalck and A. Thores, Nom. J. Chim., IO (1986) 631. 7 (a) B. Fontal, J. P. Orlewski, C. Santini and J. M. Basset, Iwg. Chem., 25 (1986) 4320; (b) W. A. Herrmann, J. A. Kulpe, W. Konkol and H. Bahrmann, J. OrgammetalL Chem, 389 (1990) 85; (c) D. J. Darensbourg, C. J. Bischoff and J. H. Reibenspies, Iwg. Chem., 30 (1991) 1144.
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8 P. S. HsUman, B. R. Garvey and G. Wilkinson, J. Chem. Sot., (A) (1968) 3143. 9 P. W. Amdtt, A. S. F. Boyd and T. A. Stephenson,J. Chem. Sot., Dalton !?hms., (1976) 1663. 10 C. A. Tolmart, C&w. Rev., 77 (1977) 313. 11 A. C. Skapski and P. G. H. Troughton, Cltem. Commurx, (1968) 1230. 12 A. C. Skapski and F. A. Stephens, J. Cha. Sot., Dalton Trans., (1974) 390. 13 S. Komiya and A. Yamamoto, J. Mol. Cat&, 5 (1979) 279. 14 D. E. L~NI and J. Halpem, J. Am. Chem Sot., 109 (1987) 2669. 15 D. F. Gill, B. E. Mann and B. L. Shaw, J. Chem Sot., Ddwn !7Vczm., (1973) 311. 16 C. R. Crooks, B. F. G. Johnson, J. Lewn and I. G. Williams, J. Chem. Sot. CA), (1969) 2761.
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Homogeneous catalysis in water Part II. Synthesis and characterization of ruthenium water-soluble complexes E. Fache, C. Santini, F. Senocq and J. M. Basset* Institut de Recherches sur la Catalyse, 2 Au. A. Einstein, 69626 ViUeurbanne C&%x O+-amej Ecole Suptkieure de Chimie Industrielle de Lyon, 43 Bd du 11 Nov. 1918, 69100 Villeurbanne (France) (Received July 23, 1991; revised December 19, 1991)
Abstract Seven water-soluble complexes of ruthenium and TPPTS have been prepared and characterized (TPPTS is the trisodium salt of the trl(m-sulfophenyl)phosphine): 3, RuH~(TPPTS)~ 4, [RuCl,(TPPTS),], 1, RuHCl(TPPTS)e 2, RuH(OAc)(TPPS), RuHI(TPPTS)e 6, RuCl,(CO),(TPPTS), 6 and [Ru(OAc)(CO),(TPPTS)]~ 7. Spectroscopic investigations have shown that in solution they have the same structures as their organosoluble analogues containing the ligand PPh,.
Introduction Since the work of Chatt on water-soluble monosulfonated triphenylphosphine [ 1, 21, numerous water-soluble liiands have been prepared 131, and, among them, the t&odium salt of tri(m-sulfophenyl)phosphine (or TPPTS) [4]. This ligand, highly water-soluble, and very sparingly soluble in organic solvents, finds industrial use in the hydroformylation of propene by rhodium moieties [ 51. It also has been used to prepare complexes of rhodium, ruthenium, osmium, iridium and other Group VI, VII and X metals [6, 71. Due to the key role of ruthenium complexes in the hydrogenation of unsaturated substrates, it appeared interesting to prepare the water-soluble analogues of the ruthenium Bison-Osborn catalysts [8]. We present here seven new compounds of ruthenium with the TPPTS ligand: [RuC12(TPPTS),], (l), RuHCl(TPPTS)a (Z), RuH(OAc)(TPPTS), (3), RuH,(TPPTS), (4), RuHI(TPPTS), (S), RuCla(CO)a(TPPTf$. (6) and [RuWWW),W’P’Wl~ (7). Classical methods to prepare Will
0304-5102/92/$5.00
0 1992 - Elsevier Sequoia. All rights reserved
332
aration has been based on a ligand exchange in biphasic medium of the classical Wilkinson catalyst by TPPTS according to the general equation: R&(PPh,),
+ nTPPTS -
RI&(TPPTS),
+ nPPha
The other methods we used involved either direct carbonylation of 1 which leads to 6, addition of stoichiometric amount of TPPTS to [Ru(CO),(OAc)], which leads to 7 or exchange of halide (Cl for I) which has also been used to obtain 6 from 2.
Experimental
1 [RuCl~(TPPXS’J2: 0.542 g of RuCla(PPh& is dissolved in 60 cm3 of THF and heated to 60 “C. A solution of 0.733 g of TPPTS in 10 cm3 of water is then added dropwise, under vigourous stirring. The stirring and heating are maintained for 30 min. Separation occurs, giving a very pale orange organic solution and a deep red aqueous solution. After gentle cooling to room temperature, the aqueous phase is collected by decantation and argon is bubbled through it for a few minutes, in order to eliminate THF. The organic phase is discarded without investigation of its components. The aqueous solution is then evaporated to dryness, to give 0.540 g (73% yield) of a red-brown solid. 2 RuHCl(TppTs),: 0.46 g of RuHCl(PPh3)3 reacts with 1 g of TPPTS according to the same procedure as that followed for 1.Overall yield is 0.68 g (70%) of a deep red solid. 3 RuH~OAc)(TppTs),: 0.54 g of RuH(OAc)(PPh,), reacts with 1.05 g of TPPTS according to the same procedure as that followed for 1. Overall yield is 0.6 g (53%) of a bright yellow solid. 4 RuH~(TppTs),: 0.694 g of RuH2(PPh3), reacts with 1.46 g of TPPTS according to same procedure followed for 1. The overall yield is 1.26 g (80%) of a deep yellow solid. 5 RuHI(TPPZS], : 0.32 g of RIIHCI(TPPTS)~(2) is dissolved with stirring at room temperature in 10 cm3 of water to give a red solution. 0.2 g of Nal (&fold excess) is added and the solution becomes purple instantaneously. The stirring is maintained for 1 h. After evaporation to dryness in VUCUQ, the purple solid is washed several times with ethanol. The yield is 0.2 g (60%). 6 RuClz(CO)z(TppTs)2: 0.1 g of 1 is dissolved in 300 cm3 of 2-(2methoxyethoxy)ethanol and heated at 100 “C for 1 h with stirring and gentle bubbling of carbon monoxide. The solution becomes progressively brown, then colourless, and a small amount of a white precipitate appears, which is eliminated by 6ltration after cooling the solution to room temperature (IR spectra of this solid shows the presence of the trcms-tram-trans isomer of 6:
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7 [Ru&‘O), (OAC)(TPPZS’]~: 0.8 g of TPPTS is dissolved in 100 cm3 of methanol at 55 “C with vigourous stirring. After dissolution, 0.14 g of [Ru(CO),(OAc)], is added. The stirring and the temperature are maintained for 15 h. The solution becomes yellow. After cooling to room temperature, a yellow solid precipitates, which is isolated by Ilkration, washed with ethanol and dried in WCZULThe yield is 0.77 g (70%). The elemental analyses are in good agreement, which the proposed formulae, but indicate the presence of very small and variables amounts of sodium sulfate, depending on the sample of TPPTS used. The NMR spectra were recorded on a Bruker AC 100 for ‘H and 13C, and on a Varian XL 100 and a Bruker WM 250 for 31P. The spectra of the water-soluble compounds have been recorded in DzO, the others in CD2C12.
Results
and discussion
[RuC~&TPPTS)~]~(1) exhibits a 31P NMR spectrum with one singlet at 6= 56.6 ppm. This resonance is very close to that at 6= 56 ppm observed by Armitt et al. at + 20 “C for [RuCl,(PPh,),], [ 91.With 1, we were unable to reach a temperature sufficiently low to observe the splitting of the signal (AB pattern), as seen with the organosoluble complex. The ‘H NMR of 1 shows only the phenylic protons, as its 13C spectrum exhibits Cl at 136.4 ppm (tr, J(P-C)=22 Hz), Cz at 139.7 ppm (broad unresolved peak), C3 at 145.0 (d, J(P-C) =4 Hz), C4 at 133.5 ppm (&P-C)=0 Hz) and Cs and Cs as two broad peaks at 131.6 and 129.9 ppm (accurate attribution was not possible). In the same conditions, the 13C spectrum of free TPPTS gives Cl at 139.2 ppm (J(P-C)= 11 Hz), Cz at 139.1 ppm @(P-C)= 18 Hz), C3 at 145.7 ppm (&P-C) = 7 Hz), C4 at 129.3 ppm (J(P-C)=O Hz), C5 at 132.4 ppm (J(P-C)=6 Hz) and CB at 132.9 ppm (J(P-C)= 21 Hz). 1 does not react with an excess of TPPTS to give the tris phosphine complex RuCl,(TPPTS),, as occurs when [RuC12(PPh3)2]2is allowed to react with PPh,. This difference in behaviour is likely due to the very large cone angle of TPPTS (cu. 170” [ 7c] compared with 145” for PPh, [lo]), which prevents coordination of a third TPPTS ligand when two chlorine atoms are already on the ruthenium. Jn water and under Hz (1 atm), 1 gives a hydrido complex, as indicated by the appearance in the ‘H NMR spectrum of a triplet at - 15.4 ppm (&P-H) = 20 Hz) which thus could be attributed to a RuHX(‘T.PPTI& moiety. This species had not been characterized. RuHCl(TPPTS)3 (2) exhibits spectral data almost identical to those of RuHCl(PPh3)3. The ‘H NMR spectra shows, besides phenylic protons, one hydride signal (quadruplet, 6= - 18.5 ppm, J(P-H) = 25 Hz), while the 31P spectra gives a broad singlet at S= 57 ppm. These data are similar to those observed for RuHCl(PPh3)3. These two compounds probably have the same fluxional distorted trigonal bipyramid structure [ 11].2 reacts with molecular hydrogen in the presence of an excess of TPPTS to give RuH&‘PPTS),, as evidenced by ‘H and 31P NMR data (vide imu).
334
RuH(OAc)(TPPTS)a (3) has spectral data similar to those of RuH(OAc)(PPh&. The 31P NMR gives an AaB pattern (&Pa)=46.4 ppm, 6(Pb) = 79.7 ppm, &P-P) = 29 Hz). The ‘H NMR shows the methyl protons of the acetato group at 1.69 ppm and the hydride as an asymmetric fourline signal centered at - 18.4 ppm (&P-H)= 26 Hz). The 13C NMR shows the methyl carbon of the acetato group at 6=25.5 ppm and the carboxylic carbon at 187.6 ppm. No coupling with phosphorus atoms is observed. The phenylic carbons appear between 129.6 ppm (C,, J(P-C)=O) and 145.2 ppm (C,, J(P-C) = 3 Hz), without any signillcant change from the spectrum of 1. Thesevalues are very close to those obtained for RuH(OAc)(PPh3)3: GP(Pa) = 43.8 ppm, GP(Pb) = 77.6 ppm, .&P-P) = 27.5 Hz; SH(Me) = 1.12 ppm, GH(Rr,+)= - 19.9 ppm, &P-H)=27 Hz; E(C-Me)=2x4 ppm, 6C(O-C-Me)= 180.8 ppm. These two compounds seem &hare the same octahedral geometry, with the three phosphorus atoms in equatorial position and the hydride in axial position [ 12 1. The spectral data of R~IzI~(TPPTS)~(4) are also similar to those of RuHz(PPh3),. At a concentration of 0.06 M, the 31P NMR gives an AzBz pattern: 6(Pa)=41.9 ppm, S(Pb)=53.9 ppm, J(P-P)=12.5 Hz (to be compared with &Pa) =46.8 ppm, S(Pb) -55.1 ppm, J(P-P)= 15 Hz obtained for H2Ru(PPh,),). The ‘H NMR in the hydride region gives a complicated signal with four intense merging lines centered at - 10.5 ppm, the apparent coupling constant being cu. 35 Hz (- 9.7 ppm and J(P-H) =40 Hz for H,Ru(PPh,),). At this concentration, a small amount of a second product is detected in the {1H}31PNMR spectrum as an AaB pattern @(Pa) = 46.5 ppm, 6(Pb) = 79.9 ppm, J(P-P) = 25 Hz) with few free TPPTS (&P) = - 5.5 ppm), and in the ‘H NMR as a small quartet at - 17.7 ppm (J(P-I-I) = cu. 25 Hz). The higher the dilution, the more important the second product and the free TPPTS are. Solvated species RuI-I,(PPh,),Q, L =pyridine [ 131, THF or cyclohexanone [ 141, with similar A,B pattern in the 31P NMR, have been observed. It is possible to propose that, in solution, we probably have the dissociation equilibrium: RuH&l’PPTS), + Ha0 =
RuHa(TPPTS),(HaO) + TPPTS
The second set of signals observed by NMR may be attributed to the solvated species RuH&l’PPTS)3(H,0). The ‘H NMR spectrum of RuHI(TPPTS)3 (6) shows one hydride signal at - 15.4 ppm (quadruplet, &P-C) = 25 Hz) and the 31P NMR spectrum a broad singlet at 59.5 ppm. Although, to our best knowledge, the organosoluble analogue RuHI(PPh,), is not known, we can assume that 6 has the same structure as 2, i.e. a fluxional distorted trigonal bipyramid. Because Da0 is the only deuterated solvent we can use with this family of water-soluble compounds, it was not possible to reach a temperature sufficiently low to observe the splitting of the NMR signals. The IR spectrum of RuCI,(CO)&~‘PPTS)~ (6) presents two v(C0) bands at 2062 and 1998 cm- ‘, indicative of two terminal carbonyl groups in cis configuration (2056 and 1991 cm-’ for RuCl,(CO),(PPh,),). The 31P NMR
335
spectrum shows one singlet at 20.7 ppm (17.4 ppm for RuCl,(CO),(PPh&,). The 13CNMR signal for CO (S= 193.6 ppm, J(P-C) -0) and for the phenylic carbons (129 to 146 ppm) are very close to those of RuC1,(C0)2(PPh,)2, (&CO) = 190 ppm). The water-soluble complex has therefore the same octahedral structure as its organosoluble analogue, with the phosphorous atoms in axial position and the two chlorine atoms in the equatorial plane with a cis configuration [ 151. With [Ru(OAC)(CO),(TPPTS)]~ (7), the 31P NMR spectrum exhibits one singlet at 16.7 ppm and the ‘H NMR gives the methyl of the acetato group as a singlet at 1.67 ppm. The 13C NMR exhibits the methyls of the acetato at 25.5 ppm, the acidic carbons at 191.5 ppm and the terminal carbonyls at 207 ppm. The NMR data for [Ru(OAc)(CO),(PPh,)], are similar: 6P = 13.7 ppm, GH(Me) = 1.15 ppm, GC(Me)=23.5 ppm, X(0-_C-Me)= 186.5 ppm and GC(Ru-CO) = 206 ppm. The IR spectra of the two compounds are very close: they show four intense
It does not seem possible to prepare RuC~~(TPPTS)~,probably for steric reasons due to the large cone angle of TPPTS as compared to that of PPhs [ 7~1. All the other ruthenium complexes that we have been able to synthesize have organosoluble analogues and seem to adopt the same geometrical conflgumtion in water. This similarity of structure is deduced from a systematic similarity in spectroscopic data (IR, 31P, ‘H and 13C NMR). Therefore, one may conclude that the main differences in coordinating properties between TPPTS and PPh3 are steric and not electronic. In the following paper of this series, we will consider the differences and analogies in the catalytic reactivity of the two families of complexes. References 1 S. Arland, J. Chat%, N. R. Davis and A. Williams, J. Chem. Sot., (1958) 276. 2 A. F. Borowski, D. J. Cole-Hamilton and G. W-on, Nom. J. Chim., 2 (1978) 137; F. Jo6, Z. T6th and M. T. Beck, Chim. Actu, 25 (1977) L61; F. Jo6 and Z. T6th, J. Mol. Cad., 8 (1980) 369; F. Jo6 and M. T. Beck, React. Kin&. CataL I.&t., 2 (1980) 257. 3 D. Sinou, B&L Sot. Chim. F’r., 3 (1987) 480. 4 Ger. Off&n., 2627354 (1976) to E. G. Kunta. 5 E. G. Kuntz, Chemtech, (1987) 570. 6 C. Larpent, R. Dabard and H. Patin, Inarg. Chenz, 26 (1987) 2922; A. Dedieu, P. Escaffre, J. M. Frances, Ph. Kalck and A. Thores, Nom. J. Chim., IO (1986) 631. 7 (a) B. Fontal, J. P. Orlewski, C. Santini and J. M. Basset, Iwg. Chem., 25 (1986) 4320; (b) W. A. Herrmann, J. A. Kulpe, W. Konkol and H. Bahrmann, J. OrgammetalL Chem, 389 (1990) 85; (c) D. J. Darensbourg, C. J. Bischoff and J. H. Reibenspies, Iwg. Chem., 30 (1991) 1144.
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8 P. S. HsUman, B. R. Garvey and G. Wilkinson, J. Chem. Sot., (A) (1968) 3143. 9 P. W. Amdtt, A. S. F. Boyd and T. A. Stephenson,J. Chem. Sot., Dalton !?hms., (1976) 1663. 10 C. A. Tolmart, C&w. Rev., 77 (1977) 313. 11 A. C. Skapski and P. G. H. Troughton, Cltem. Commurx, (1968) 1230. 12 A. C. Skapski and F. A. Stephens, J. Cha. Sot., Dalton Trans., (1974) 390. 13 S. Komiya and A. Yamamoto, J. Mol. Cat&, 5 (1979) 279. 14 D. E. L~NI and J. Halpem, J. Am. Chem Sot., 109 (1987) 2669. 15 D. F. Gill, B. E. Mann and B. L. Shaw, J. Chem Sot., Ddwn !7Vczm., (1973) 311. 16 C. R. Crooks, B. F. G. Johnson, J. Lewn and I. G. Williams, J. Chem. Sot. CA), (1969) 2761.