Formation of Imine− Vinylidene− Osmium (II) Derivatives by Hydrogen

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Organometallics 2000, 19, 5454-5463

Formation of Imine-Vinylidene-Osmium(II) Derivatives by Hydrogen Transfer from Alkenyl Ligands to Azavinylidene Groups in Alkenyl-Azavinylidene-Osmium(IV) Complexes Ricardo Castarlenas, Miguel A. Esteruelas,* and Enrique Onãte Departamento de Quı´mica Ino´ rganica-Instituto de Ciencia de Materiales de Arago´ n, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain Received June 21, 2000

Treatment at room temperature of the hydride-azavinylidene complexes OsHCl2(dNdCR2)(PiPr3)2 [CR2 ) CMe2 (1), C(CH2)4CH2 (2)] with Ag[CF3SO3] and the subsequent addition at -25 °C of phenylacetylene to the resulting solutions affords the alkenyl-azavinylidene derivatives [Os{(E)-CHdCHPh}Cl(dNdCR2)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (3), C(CH2)4CH2 (4)], where the Hβ atoms of the alkenyl ligands interact with the osmium atoms to form agostic bonds. The addition at -30 °C of NaCl to tetrahydrofuran solutions of 3 and 4 produces the split of the agostic interactions and the formation of the neutral six-coordinate alkenyl-azavinylidene compounds Os{(E)-CHdCHPh}Cl2(dNdCR2)(PiPr3)2 [CR2 ) CMe2 (5), C(CH2)4CH2 (6)]. In dichloromethane at room temperature complexes 5 and 6 evolve into the imine-vinylidene derivatives OsCl2(dCdCHPh)(NHdCR2)(PiPr3)2 [CR2 ) CMe2 (7), C(CH2)4CH2) (8)], as a result of the hydrogen transfer from the styryl ligands to the azavinylidene groups. The structure of 7 in the solid state has been determined by an X-ray diffraction study. The geometry around the metal center could be described as a distorted octahedron with the imine group disposed trans to a chlorine atom and cis to the other one. The N-H hydrogen atom of the imine interacts with the latter to form an intramolecular N-H‚‚‚Cl hydrogen bond, which is manifested by a short Cl‚‚‚‚H separation of 2.366 Å and a Cl-Os-N angle of 77.34(18)°, largely deviated from the ideal value of 90°. Complexes 3 and 4 also react with water at -20 °C to give the cationic imine-vinylidene derivatives [OsCl(dCdCHPh)(NHdCR2)(H2O)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (9), C(CH2)4CH2 (10)]. The structure of 9 in the solid state has been also determined by an X-ray diffraction study. The geometry around the metal center is octahedral with the imine group disposed trans to chlorine atom and cis to the water molecule. In this case the N-H hydrogen atom of the imine interacts with the oxygen atom of water molecule. The N-H‚‚‚O hydrogen bond is manifested by an O‚‚‚H separation of 2.36 Å and a N-Os-O angle of 78.3(2)°. The formation of 9 and 10 proceeds via the cationic six-coordinate alkenyl-azavinylidene-osmium(IV) intermediates [Os{(E)-CHdCHPh}Cl(dNdCR2)(H2O)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (11), C(CH2)4CH2 (12)], which have been characterized in solution at -90 °C by 1H and 31P{1H} NMR spectroscopy. Complexes 3 and 4 react with acetonitrile to give [OsCl(dCdCHPh)(NHdCR2)(CH3CN)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (13), C(CH2)4CH2 (14)] via the intermediates [Os{(E)-CHdCHPh}Cl(dNdCR2)(CH3CN)(PiPr3)2[CF3SO3] [CR2 ) CMe2 (15), C(CH2)4CH2 (16)]. Introduction Vinylidene complexes are considered the central point of important selective transformations of terminal alkynes with atom economy.1 Several methods have been employed for their preparation.2 The most straight(1) Bruneau, C.; Dixneuf, P. H. Acc. Chem. Res. 1999, 32, 311. (2) Bruce, M. I. Chem. Rev. 1991, 91, 197.

forward route arises from the activation of terminal alkynes which, depending upon of the nucleophilicity of the metallic center, initially give η2-coordinated alkyne or alternatively hydride-alkynyl intermediates. The η2-alkynes evolve by direct 1,2-hydrogen migration over the carbon-carbon triple bond. The hydridealkynyl intermediates dissociate the hydride as a proton to yield alkynyl species; subsequently, the protonation

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Imine-Vinylidene-Osmium(II) Derivatives

of the alkynyl group at the Cβ atom affords the vinylidene derivatives.3 In agreement with the last, the electrophilic addition to alkynyl complexes has shown to be also a general strategy to prepare vinylidene complexes.2 In addition, the deoxygenation of acylmetal derivatives by treatment with (CF3SO2)2O,4 the deprotonation of metal carbynes,5 the rearrangement of alkylidene metallacyclobutane species,6 and the reduction of allenylidene compounds should be mentioned.7 With some exceptions,8 from hydride complexes, the most favored pathway is the insertion of the triple bond of terminal alkynes into the M-H bonds to form alkenyl intermediates, which undergo R-hydrogen elimination.9 The dehydrochlorination of chloroalkenyl compounds has been also used.2,10 Imine complexes are intermediate states during the transformations between amine and nitrile derivatives.11 However, there are comparatively few examples of monodentate nitrogen-bonded imine compounds, as a consequence of the weak Lewis basicity of the imine nitrogen atom,12 and the vulnerability of the imines to (3) (a) Silvestre, J.; Hoffmann, R. Helv. Chem. Acta 1985, 68, 1461. (b) Wakatsuki, Y.; Koga, N.; Yamazaki, H.; Morokuma, K. J. Am. Chem. Soc. 1994, 116, 8105. (c) de los Rios, I.; Jimeńez-Tenorio, M.; Puerta, M. C.; Valerga, P. J. Chem. Soc., Chem. Commun. 1995, 1757. (d) Wakatsuki, Y.; Koga, N.; Werner, H.; Morokuma, K. J. Am. Chem. Soc. 1997, 119, 360. (e) de los Rios, I.; Jimeńez-Tenorio, M.; Puerta, M. C.; Valerga, P. J. Am. Chem. Soc. 1997, 119, 6529. (f) Bustelo, E.; Jimeńez-Tenorio, M.; Puerta, M. C.; Valerga, P. Organometallics 1999, 18, 950. (g) Bustelo, E.; Jimeńez-Tenorio, M.; Puerta, M. C.; Valerga, P. Organometallics 1999, 18, 4563. (h) Puerta, M. C.; Valerga, P. Coord. Chem. Rev. 1999, 193-195, 977. (i) Baya, M.; Crochet, P.; Esteruelas, M. A.; Gutie´rrez-Puebla, E.; Lo´pez, A. M.; Modrego, J.; Onãte, E.; Vela, N. Organometallics 2000, 19, 2585. (4) (a) Boland-Lussier, B. E.; Churchill, M. R.; Hughes, R. P.; Rheingold, A. L. Organometallics 1982, 1, 628. (b) Bly, R. S.; Raja, M.; Bly, R. K. Organometallics 1992, 11, 1220. (5) (a) Baker, P. K.; Barber, G. K.; Green, M.; Welch, A. J. J. Am. Chem. Soc. 1980, 102, 7811. (b) Gill, D. S.; Green, M. J. Chem Soc., Chem. Commun. 1981, 1037. (c) Bourgault, M.; Castillo, A.; Esteruelas M. A.; Onãte, E.; Ruiz, N. Organometallics 1997, 16, 636. (e) Esteruelas, M. A.; Olivań, M.; Onãte, E.; Ruiz, N.; Tajada, M. A. Organometallics 1999, 18, 2953. (e) Buil, M. L.; Eisenstein, O.; Esteruelas, M. A.; Garcıá-Yebra, C.; Gutie´rrez-Puebla, E.; Olivań, M.; Onãte, E.; Ruiz, N.; Tajada M. A. Organometallics 1999, 18, 8, 4949. (f) Buil, M. L.; Esteruelas, M. A.; Garcıá-Yebra, C.; Gutie´rrez-Puebla, E.; Olivań, M. Organometallics 2000, 19, 2184. (6) Buchwald, S. L.; Grubbs, R. H. J. Am. Chem. Soc. 1983, 105, 5490. (7) Crochet, P.; Esteruelas, M. A.; Lo´pez, A. M.; Ruiz, N.; Tolosa, J. I. Organometallics 1998, 17, 3479. (8) (a) Esteruelas, M. A.; Oro L. A.; Valero, C. Organometallics 1995, 14, 3596. (b) Crochet P.; Esteruelas, M. A.; Lo´pez, A. M.; Martıńez, M.-P.; Olivań, M.; Onãte, E.; Ruiz, N. Organometallics 1998, 17, 4500. (9) (a) van Asselt, A.; Burger, B. J.; Gibson, V. C.; Bercaw, J. E. J. Am. Chem. Soc. 1986, 108, 5347. (b) Dziallas, M.; Werner, H. J. Organomet. Chem. 1987, 333, C29. (c) Beckhaus, R.; Thiele, K.-H.; Stro¨hl, D. J. Organomet. Chem. 1989, 369, 43. (d) Bell, T. W.; Haddleton, D. M.; McCamley, A.; Partridge, M. G.; Perutz, R. N.; Willner, H. J. Am. Chem. Soc. 1990, 112, 9212. (e) Gibson, V. C.; Parkin, G.; Bercaw, J. E. Organometallics 1991, 10, 220. (f) Beckhaus, R. J. Chem. Soc., Dalton Trans. 1997, 1991. (g) Luinstra, G. A.; Teuben, J. H. Organometallics 1992, 11, 1793. (h) Beckhaus, R. Angew. Chem., Int. Ed. Engl. 1997, 36, 686. (i) Alvarado, Y.; Boutry, O.; Gutie´rrez, E.; Monge, A.; Nicasio, M. C.; Poveda, M. L.; Pe´rez, P. J.; Ruı´z, C.; Bianchini, C.; Carmona E. Chem. Eur. J. 1997, 3, 860. (j) Olivań, M.; Clot, E.; Eisenstein, O.; Caulton, K. G. Organometallics 1998, 17, 3091. (10) Weinand, R.; Werner, H. J. Chem. Soc., Chem. Commun. 1985, 1145. (11) (a) Ridd, M. J.; Keene, F. R. J. Am. Chem. Soc. 1981, 103, 5733. (b) Adcock, P. A.; Keene, F. R. J. Am. Chem. Soc. 1981, 103, 6494. (c) Feng, S. G.; Templeton, J. L. J. Am. Chem. Soc. 1989, 111, 6477. (d) Feng, S. G.; Templeton, J. L. Organometallics 1992, 11, 1295. (e) Yeh, W.-Y.; Ting, C.-S.; Peng, S.-M.; Lee, G.-H. Organometallics 1995, 14, 1417. (f) Gunnoe, T: B.; White, P. S.; Templeton, J. L. J. Am. Chem. Soc. 1996, 118, 6916. (g) Francisco, L. W.; White, P. S.; Templeton, J. L. Organometallics 1996, 15, 5127. (12) Mehrota, R. C. In Comprehensive Coordination Chemistry; Wilkinson, G.; Gillard, R. D., McCleverty, J. A., Eds.; Pergamon: Oxford, England, 1987; Vol 2, pp 269-287.

Organometallics, Vol. 19, No. 25, 2000 5455

nucleophilic attack, to form functionalized amines.13 In particular, complexes containing N-protio imines with low molecular weight have proven difficult to isolate. The reaction of Cr(CO)5{dC(OMe)Me} with oximes of aliphatic, alicyclic, and aromatic ketones affords Cr(CO)5(NHdCRR′), including dimethyl imine.14 Related compounds of chromium, molybdenum, tungsten, and iron have been prepared from the corresponding metalammonia starting materials and ketones.15 The benzophenone imine derivatives M(CO)5(NHdCPh2) (M ) Cr, W) have been synthesized by reaction of M(CO)5(dCPh2) with trimethylsilyl azide.16 Gladysz and co-workers have reported imine complexes of the type [Re(η5-C5H5)(NO)(NHdCRR′)(PPh3)][CF3SO3], which are obtained by displacement of triflate by the free imine or by addition of nucleophiles to cationic nitrile complexes followed by protonation.17 Complexes Os(C2Ph)2(CO)(NHdCPh2)(PiPr3)218 and MHCl(CO)(NHdCPh2)(PiPr3)2 (M ) Ru,19a Os19b) have been obtained by addition of benzophenone imine to the corresponding five-coordinate precursors. The protonation of OsH(CO)(NHdC(Ph)C6H4}(CO)(PiPr3)2 with HBF4‚OEt2 gives [OsH(CO)(NHdCPh2)(PiPr3)2]BF4, which by reaction with carbon monoxide or trimethyl phosphite affords [OsH(CO)(NHdCPh2)L(PiPr3)2]BF4 [L ) CO, P(OMe)3].20 Half-sandwich ruthenium and osmium complexes containing aldimine and benzophenone imine ligands have been also synthesized.21 We have recently reported that the dihydridedichloro complex OsH2Cl2(PiPr3)2 reacts with acetone oxime and cyclohexanone oxime in the presence of Et3N to give the dihydride derivatives OsH2Cl(κ2-ONdCR2)(PiPr3)2 [CR2 ) CMe2, C(CH2)4CH2],22 which afford the corresponding hydride-azavinylidene-osmium(IV) complexes OsHCl2(dNdCR2)(PiPr3)2 by addition of HCl.23 As a part of our work on the reactivity of transition (13) (a) Hoberg, H.; Go¨tz, V.; Kru¨ger, C.; Tsay, Y. H.J. Organomet. Chem. 1979, 169, 209. (b) Buchwald, S. L.; Watson, B. T.; Wannamaker, M. W.; Dewan, J. C. J. Am. Chem. Soc. 1989, 111, 4486. (c) Durfee, L. D.; Hill, J. E.; Fanwick, P. E.; Rothwell, I. P. Organometallics 1990, 9, 75. (d) Martin, G. C.; Boncella, J. M.; Wucherer, E. J. Organometallics 1991, 10, 2804. (e) Faller, J. W.; Ma, Y.; Smart, C. J.; Diverdi, M. J. J. Organomet. Chem. 1991, 420, 237. (f) Richter-Addo, G. B.; Knight, D. A.; Dewey, M. A.; Arif, A. M.; Gladysz, J. A. J. Am. Chem. Soc. 1993, 115, 11863. (g) Cantrell, W. R., Jr.; Richter-Addo, G. B.; Gladysz, J. A. J. Organomet. Chem. 1994, 472, 195. (14) Fischer, E. O.; Knauss, L. Chem. Ber. 1970, 103, 1262. (15) Sellmann, D.; Thallmair, E. J. Organomet. Chem. 1979, 164, 337. (16) Fischer, H.; Zeuner, S. J. Organomet. Chem. 1985, 286, 201. (17) (a) Knight, D. A.; Dewey, M. A.; Stark, G. A.; Bennett, B. K.; Arif, A. M.; Gladysz, J. A. Organometallics 1993, 12, 4523. (b) Stark, G. A.; Gladysz, J. A. Inorg. Chem. 1996, 35, 5509. (18) Esteruelas, M. A.; Lahoz, F. J.; Lo´pez, A. M.; Onãte, E.; Oro, L. A. Organometallics 1995, 14, 2496. (19) (a) Bohanna, C.; Esteruelas, M. A.; Lo´pez A. M.; Oro L. A. J. Organomet. Chem. 1996, 526, 73. (b) Daniel, T.; Werner, H. Z. Naturforsch. B 1992, 47, 1707. (20) Albeńiz, M. J.; Buil, M. L.; Esteruelas, M. A.; Lo´pez, A. M. J. Organomet. Chem. 1997, 545-546, 495. (21) (a) Faller, J. W.; Ma, Y.; Smart, C. J.; Diverdi, M. J. J. Organomet. Chem. 1991, 420, 273. (b) Daniel, T.; Mu¨ller, M.; Werner, H. Inorg. Chem. 1991, 30, 3120. (c) Daniel, T.; Knaup, W.; Dziallas, M.; Werner, H. Chem. Ber. 1993, 126, 1981. (d) Werner, H.; Daniel, T.; Knaup, W.; Nu¨rnberg, O. J. Organomet. Chem. 1993, 462, 309. (e) Werner, H.; Daniel, T.; Braun, T.; Nu¨rnberg, O. J. Organomet. Chem. 1994, 480, 145. (22) Castarlenas, R.; Esteruelas, M. A.; Gutie´rrez-Puebla, E.; Jean, Y.; Lledo´s, A.; Martıń, M.; Toma`s, J. Organometallics 1999, 18, 4296. (23) Castarlenas, R.; Esteruelas, M. A.; Gutie´rrez-Puebla, E.; Jean, Y.; Lledo´s, A.; Martıń, M.; Onãte, E,; Toma`s, J. Organometallics 2000, 19, 3100.

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Organometallics, Vol. 19, No. 25, 2000 Scheme 1

metal hydride complexes toward terminal alkynes,24 we have now investigated the reactions of the abovementioned hydride-azavinylidene compounds with phenylacetylene. In this paper, we report the discovery of a novel reaction, the hydrogen transfer from a styryl ligand to azavinylidene groups, which affords complexes containing both functional groups vinylidene and imine. Results and Discussion Formation and Characterization of Neutral Imine-VinylideneComplexes.ComplexesOsHCl2(dNd CR2)(PiPr3)2 [CR2 ) CMe2 (1), C(CH2)4CH2 (2)] do not react with phenylacetylene due to their saturated character. However, the treatment at room temperature of dichloromethane solutions of 1 and 2 with 1.0 equiv of Ag[CF3SO3] and the subsequent addition at -25 °C of 1.2 equiv of phenylacetylene affords, after 5 h, the alkenyl-azavinylidene complexes [Os{(E)-CHdCHPh}Cl(dNdCR2)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (3), C(CH2)4CH2 (4)], as a result of the extraction of a chlorine ligand from 1 and 2 and the insertion of the carboncarbon triple bond of the alkyne into the Os-H bonds of the resulting unsaturated intermediates (Scheme 1). The unsaturated character of 3 and 4 is strongly supported by the IR spectra of these compounds in KBr, which contain the characteristic stretching bands of the free [CF3SO3] anion25 at about 1270, 1230, 1160, and 1030 cm-1. The 1H NMR spectra at room temperature confirm the presence of the styryl groups with an E stereochemistry and suggest that the Hβ atoms of the alkenyl ligands interact with the osmium atoms of 3 and 4 to form agostic bonds. Thus, the resonances corresponding to the vinylic HR atoms appear at 7.81 (3) and 7.84 (4) ppm, in agreement with the chemical shifts observed in other osmium- and ruthenium-styryl complexes.26 However, the resonances due to the vinylic Hβ atoms are observed at 3.92 (3 and 4) ppm, shifted (24) Buil, M. L.; Elipe, S.; Esteruelas, M. A.; Onãte, E.; Peinado, E.; Organometallics 1997, 16, 5748, and references therein. (25) Lawrence, G. A. Chem. Rev. 1986, 86, 17. (26) Werner, H.; Esteruelas, M. A.; Otto, H. Organometallics 1986, 5, 2295.

Castarlenas et al.

between 2 and 4 ppm to higher field in comparison with those found in styryl complexes without agostic interaction. The value of the Hβ-P coupling constant in 3 (the Hβ resonance of 4 appears as a broad signal) of 10.2 Hz is also unusual and higher than that observed in styryl compounds without agostic interaction (about 2 Hz).26 In contrast, the values of the HR-Hβ coupling constants (11.7 Hz for 3 and 10.8 Hz for 4) are lower than that expected for an E arrangement of the alkenyl groups (between 16 and 18 Hz),26 but compare well with that found in the complex OsH{C6H4-2-(E-CHdCHPh)}(CO)(PiPr3)2 (13.6 Hz),27 where the E stereochemistry at the carbon-carbon double bond and the agostic Os-Hβ interaction have been proven by X-ray diffraction analysis. Despite the low values of the HR-Hβ coupling constant, the E stereochemistry at the carbon-carbon double bond of the styryl groups of 3 and 4 is a fact. The saturation of the HR resonance of 3 increases the intensity of the ortho-H resonance of the phenyl group (23%), while the Hβ resonance does not show any NOE effect. In the 13C{1H} NMR spectra at -40 °C, the CR atoms of the styryl ligands give rise to triplets at 144.0 (3) and 143.6 (4) with C-P coupling constants of 6 and 5 Hz, respectively, whereas the Cβ atoms display broad signals at 137.5 ppm in both cases. The resonances corresponding to the CdN carbon atoms of the azavinylidene ligands appear at 160.6 (3) and 161.9 (4) as broad signals. The 31P{1H} NMR spectra show singlets at 0.1 (3) and 2.1 (4) ppm, in agreement with the mutually trans disposition of the phosphine ligands. Complexes 3 and 4, which were isolated as green solids in high yield (about 70%), are stable for one month if kept as solids under argon at -20 °C. In solution of dichloromethane they are stable for a few hours at temperatures lower than 0 °C. At room temperature they evolve into mixtures of five products, according to the 31P{1H} NMR spectra of the mixtures. The addition at -30 °C of 3.6 equiv of NaCl to tetrahydrofuran solutions of 3 and 4 leads to the neutral alkenylazavinylidene derivatives Os{(E)-CHdCHPh}Cl2(dNdC R2)(PiPr3)2 [CR2 ) CMe2 (5), C(CH2)4CH2 (6)], as expected from the lability of the agostic interactions. Complexes 5 and 6, which were isolated as orange solids in about 80% yield, are the result of the kinetically disfavored insertion of phenylacetylene into the Os-H bonds of 1 and 2. In the IR spectra of 5 and 6, the most noticeable feature is the absence of any band due to the [CF3SO3]anion. The 1H NMR spectra reflect the split of the agostic interactions as a consequence of the coordination of chlorine to 3 and 4. Thus, the vinyl resonances of the styryl ligands are observed at about 12 and 5 ppm, as doublets with HR-Hβ coupling constants of about 17 Hz. The spectra also reflect the mutually cis disposition of the chlorine ligands, showing two iPr-methyl chemical shifts as a result of the prochirality of the phosphorus atom of the phosphines. In the 13C{1H} NMR spectra, the CR atoms of the styryl ligands give rise to triplets at 133.4 (5) and 138.9 (6) ppm, with C-P coupling constants of 3.5 and 2.8 Hz, respectively, whereas the resonances corresponding to the Cβ atoms are observed as singlets at 139.4 (5) and 137.5 (6) ppm. The CdN (27) Esteruelas, M. A.; Lahoz, F. J.; Onãte, E.; Oro, L. A.; Sola, E. J. Am. Chem. Soc. 1996, 118, 89.



phosphorus atoms of the triisopropylphosphine in trans position [P(1)-Os-P(2) ) 174.99(8)°]. The perpendicular plane is formed by the chlorine ligands mutually cis disposed [Cl(1)-Os-Cl(2) ) 89.50(7)°], the C(4) atom of the vinylidene trans disposed to Cl(2) [Cl(2)-Os-C(4) ) 170.9(2)°], and the nitrogen atom of the imine group trans disposed to Cl(1) [Cl(1)-Os-N ) 166.03(16)°]. The vinylidene ligand is bound to the metal in a nearly linear fashion with an Os-C(4)-C(5) angle of 173.7(6)°. The Os-C(4) [1.820(6) Å] and C(4)-C(5) [1.322(9) Å] bond lengths compare well with those found in other osmium-vinylidene28 complexes and support the vinylidene formulation. The imine ligand is bound to the metal in a bent fashion, with a Os-N-C(1) angle of 142.5(6)°, which compares well with the Re-N-C angle found in the complex [Re(η5-C5H5)(NO)(NHdCPh2)(PPh3)]+ [136.2(3)°].17a The Os-N distance [2.072(7) Å] is between 0.2 and 0.3 Å longer than those reported in the related Figure 1. Molecular diagram for OsCl2(dCdCHPh)(NHd CMe2)(PiPr3)2 (7). Thermal ellipsoids are shown at 50% probability. Table 1. Selected Bond Lengths (Å) and Angles (deg) for the Complex OsCl2(dCdCHPh)(NHdCMe2)(PiPr3)2 (7) Os-Cl(1) Os-Cl(2) Os-P(1) Os-P(2) Os-N Os-C(4) Cl(1)-Os-Cl(2) Cl(1)-Os-P(1) Cl(1)-Os-P(2) Cl(1)-Os-N Cl(1)-Os-C(4) Cl(2)-Os-P(1) Cl(2)-Os-P(2) Cl(2)-Os-N Cl(2)-Os-C(4) P(1)-Os-P(2) P(1)-Os-N

2.4165(19) 2.5669(19) 2.466(2) 2.447(2) 2.072(7) 1.820(6) 89.50(7) 85.95(7) 89.06(8) 166.03(16) 96.7(2) 92.90(7) 86.60(7) 77.34(18) 170.9(2) 174.99(8) 90.00(18)

N-C(1) C(1)-C(2) C(1)-C(3) C(4)-C(5) C(5)-C(6) N-H(01) P(1)-Os-C(4) P(2)-Os-N P(2)-Os-C(4) N-Os-C(4) Os-N-C(1) Os-C(4)-C(5) N-C(1)-C(2) N-C(1)-C(3) C(2)-C(1)-C(3) C(4)-C(5)-C(6)

1.270(9) 1.523(11) 1.473(10) 1.322(9) 1.453(10) 0.87(7) 94.1(2) 94.75(19) 86.9(2) 96.9(3) 142.5(6) 173.7(6) 119.5(7) 124.5(8) 116.0(7) 126.2(7)

carbon atoms of azavinylidene ligands display singlets at about 151 ppm. The 31P{1H} spectra contain singlets at -51.4 (5) and -49.6 (6) ppm. Complexes 5 and 6 are stable for long times if kept as solids under argon at temperatures lower than -20 °C. In solution of chloroform-d or dichloromethane-d2, they are also stable for a few hours at temperatures lower than 0 °C. At room temperature, they slowly evolve into the imine-vinylidene derivatives OsCl2(dCdCHPh)(NHdCR2)(PiPr3)2 [CR2 ) CMe2 (7), C(CH2)4CH2 (8)], as a result of the hydrogen transfer from the styryl ligand to the azavinylide groups (Scheme 1). Complexes 7 and 8 were isolated as orange solids in 80 and 78% yield, respectively, and characterized by MS, elemental analysis, and IR, 1H, 13C{1H}, and 31P{1H} NMR spectroscopy. Complex 7 was further characterized by an X-ray crystallographic study. A view of the molecular geometry of this complex is shown in Figure 1. Selected bond distances and angles are listed in Table 1. The geometry around the osmium atom can be rationalized as a distorted octahedron with the two

azavinylidene complexes OsHCl2{dNdC(CH2)4CH2}(PiPr3)2 [1.789(12) and 1.777(12) Å] and OsCl3{dNdC(CH2)4CH2}(PiPr3)2 [1.808(10) and 1.806(10) Å]23 and supports the Os-N single bond formulation. The N-C(1) bond length [1.270(9) Å] is similar to those observed in other imine transition metal complexes (about 1.27 Å),17a,29 azavinylidene compounds (between 1.27 and 1.30 Å),23 organic azaallenium cations (between 1.23 and 1.33 Å),30 and the 2-azaallenyl complexes Cr{C(OEt)d NdCtBu2}(CO)5 [1.272(5) and 1.264(5) Å],31 Cr{C(Ph)d NdCHPh}(CO)5 [1.260(4) and 1.265(4) Å],32 and [Ru(η5C5H5){C(CHdCPh2)dNdCPh2}(CO)(PiPr3)]+ [1.283(9) and 1.252(9) Å].33 The imine H(N) hydrogen atom was found in the difference Fourier maps and refined as an isotropic atom together with the rest of the non-hydrogen atoms of the structure, giving a N-H(N) distance of 0.87(7) Å. Interestingly, the separation between this atom and the chlorine ligand Cl(2) (2.366 Å) is shorter than the sum of the van der Waals radii of hydrogen and chlorine [rvdw(H) ) 1.20, rvdw(Cl) )1.80 Å ], suggesting that there is an intramolecular Cl‚‚‚H-N hydrogen bond between these atoms, as a result of the interaction of the electronegative chlorine atom with the acidic N-H hydrogen. The Cl‚‚‚H interaction gives rise to a fourmembered Os-Cl‚‚‚H-N ring, which is almost planar (28) (a) Huang, D.; Olivań, M.; Huffman, J. C.; Eisenstein, O.; Caulton, K. G. Organometallics 1998, 17, 4700. (b) Bohanna, C.; Buil, M. L.; Esteruelas, M. A.; Onãte, E.; Valero, C. Organometallics 1999, 18, 5176, and references therein. (29) Kukushkin, V. Y.; Pakhomova, T. B.; Kukushkin, Y. N.; Herrman, R.; Wagner, G.; Pombeiro, A. J. L. Inorg. Chem. 1998, 37, 6511. (30) (a) Jochims, J. C.; Abu-El-Halawa, R.; Jibril, I.; Huttner, G. Chem. Ber. 1984, 117, 1900. (b) Al-Talib, M.; Jochims, J. C. Chem. Ber. 1984, 117, 3222. (c) Al-Talib, M.; Jibril, I.; Wu¨rthwein, E.-U.; Jochims, J. C.; Huttner, G. Chem. Ber. 1984, 117, 3365. (d) Kupfer, R.; Wu¨rthwein, E.-U.; Nagel, M.; Allmann, R. Chem. Ber. 1985, 118, 643. (e) Al-Talib, M.; Jibril, I.; Huttner, G.; Jochims, J. C. Chem. Ber. 1985, 118, 1876. (f) Al-Talib, M.; Jochims, J. C.; Zsolnai, L.; Huttner, G. Chem. Ber. 1985, 118, 1887. (g) Wu¨rthwein, E.-U.; Kupfer, R.; Allmann, R.; Nagel, M. Chem. Ber. 1985, 118, 3632. (h) Krestel, M.; Kupfer, R.; Wu¨rthwein, E.-U. Chem. Ber. 1987, 120, 1271. (31) Seitz, F.; Fischer, H.; Riede, J. J. Organomet. Chem. 1985, 287, 87. (32) Aumann, R.; Althaus, S.; Kru¨ger, S.; Betz, P. Chem. Ber. 1989, 122, 357. (33) Esteruelas, M. A.; Go´mez, A. V.; Lahoz, F. J.; Lo´pez, A. M.; Onãte, E.; Oro, L. A. Organometallics 1996, 15, 3423.

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Castarlenas et al. Table 2. Selected Bond Lengths (Å) and Angles (deg) for the Complex [OsCl(dCdCHPh)(NHdCMe2)(H2O)(PiPr3)2] [CF3SO3]‚C4H8O (9) Os-Cl Os-P(1) Os-P(2) Os-N Os-O(4) Os-C(1) Cl-Os-P(1) Cl-Os-P(2) Cl-Os-O(4) Cl-Os-N Cl-Os-C(1) P(1)-Os-P(2) P(1)-Os-O(4) P(1)-Os-N P(1)-Os-C(1) P(2)-Os-O(4)

Figure 2. Molecular diagram for the cation of [OsCl(d CdCHPh)(NHdCMe2)(H2O)(PiPr3)2][CF3SO3] (9). Thermal ellipsoids are shown at 50% probability.

with the plane containing the Os, C(4), N, Cl(1), and Cl(2) atoms. The dihedral angle between this plane and that containing the N, C(1), C(3), and C(2) atoms is 14.9°. The Cl‚‚‚H-N hydrogen bond appears to have a strong influence on the Cl(2)-Os-N angle [77.34(18)°], which largely deviates from the ideal value of 90°. Of great importance in biological and organic chemistry,34 the hydrogen bonding is presently attracting considerable interest in the chemistry of transition metals.5d,35 In agreement with the presence of imine ligands in 7 and 8, the IR spectra of these compounds in KBr contain ν(N-H) bands at 3216 (7) and 3202 (8) cm-1. In the 1H NMR spectra, the N-H resonances appear at about 11 ppm. These spectra, as those of 5 and 6, are in accordance with the mutually cis disposition of the chlorine ligands, showing two iPr-methyl chemical shifts. In addition, they contain triplets with H-P coupling constants of about 2 Hz, between 1 and 2 ppm, which correspond to the dCH hydrogen atoms of the vinylidene ligands. In the 13C{1H} NMR spectra, the resonances due to the CR carbon atoms of the vinylidene ligands are observed at about 295 ppm as triplets with C-P coupling constants of 10.0 (7) and 8.3 (8) Hz, whereas those corresponding to the Cβ atoms appear at (34) Jeffrey, G. A.; Saenger, W. Hydrogen Bonding in Biological Structures; Springer: Berlin, 1991. (35) (a) Stevens, R. C.; Bau, R.; Milstein, D.; Blum, O.; Koetzle, T. F. J. Chem. Soc., Dalton Trans. 1990, 1429. (b) Lough, A. J.; Park, S.; Ramachandran, R.; Morris, R. H. J. Am. Chem. Soc. 1994, 116, 8356. (c) Shubina, E. S.; Belkova, N. V.; Krilov, A. N.; Vorontsov E. V.; Epstein, L. M.; Gusev, D. G.; Niedermann, M.; Berke, H. J. Am. Chem. Soc. 1996, 118, 1105. (d) Braga, D.; Grepioni, F.; Desiraju, G. R. J. Organomet. Chem. 1997, 548, 33. (e) Ayllon, J. A.; Sabo-Etienne, S.; Chaudret, B.; Ulrich, S.; Limbad, H.-H. Inorg. Chim. Acta 1997, 259, 1. (f) Aime, S.; Gobetto, R.; Valls, E. Organometallics 1997, 16, 5140. (g) Crabtree, R. H.; Eisenstein, O.; Sini, G.; Peris, E. J. Organomet. Chem. 1998, 567, 7. (h) Crabtree, R. H. J. Organomet. Chem. 1998, 577, 111. (i) Yandulov, D. V.; Caulton, K. G.; Belkova, N. V.; Shubina, E. S., Epstein, L. M.; Khoroshun, D. V.; Musaev, D. G.; Morokuma, K. J. Am. Chem. Soc. 1998, 120, 12553. (j) Gusev, D. G.; Lough, A. J.; Morris, R. H. J. Am. Chem. Soc. 1998, 120, 13138. (k) Buil, M. L.; Esteruelas, M. A.; Onãte, E.; Ruiz, N. Organometallics 1998, 17, 3346. (l)Lee, D.-H.; Kwon, H. J.; Patel, B. P.; Liable-Sands, L. M.; Rheingold, A. L.; Crabtree, R. H. Organometallics 1999, 18, 1615. (m) Esteruelas, M. A.; Gutie´rrez-Puebla, E.; Lo´pez, A. M.; Onãte, E.; Tolosa, J. I. Organometallics 2000, 19, 275.

2.3959(18) 2.4663(18) 2.4679(19) 2.067(5) 2.281(6) 1.803(7) 91.68(6) 86.20(6) 81.53(16) 158.55(18) 99.5(2) 177.42(7) 87.36(15) 94.59(17) 87.7(2) 93.78(15)

N-C(9) C(9)-C(10) C(9)-C(11) C(1)-C(2) C(2)-C(3) P(2)-Os-N P(2)-Os-C(1) O(4)-Os-N O(4)-Os-C(1) N-Os-C(1) Os-N-C(9) Os-C(1)-C(2) N-C(9)-C(10) N-C(9)-C(11) C(1)-C(2)-C(3)

1.290(10) 1.494(11) 1.492(11) 1.344(10) 1.464(10) 87.91(17) 91.2(2) 78.3(2) 175.0(3) 101.2(3) 142.7(6) 176.5(6) 120.4(8) 123.1(7) 127.0(7)

about 114 ppm, also as triplets but with C-P coupling constants of about 3 Hz. The CdN carbon atoms of the imine groups display singlets between 177 and 183 ppm. The 31P{1H} NMR spectra show singlets at -21.7 (7) and -20.8 (8) ppm. Formation and Characterization of Cationic Imine-Vinylidene Complexes. When the reactions of 1 and 2 with Ag[CF3SO3] and phenylacetylene are carried out in humid solvents, the cationic iminevinylidene complexes [OsCl(dCdCHPh)(NHdCR2)(H2O) (PiPr3)2][CF3SO3] [CR2 ) CMe2 (9), C(CH2)4CH2 (10)], containing a coordinated water molecule, are formed. These compounds are obtained as red solids in about 70% yield, by addition at -20 °C of 1 equiv of water to tetrahydrofuran solutions of 3 and 4 (eq 1).

Figure 2 shows a view of the molecular geometry of 9. Selected bond distances and angles are listed in Table 2. The geometry around the osmium atom can be described as a distorted octahedron with the two phosphorus atoms of the phosphine ligands in trans position [P(1)-Os-P(2) ) 177.42(7)°]. The chlorine, vinylidene, imine, and water ligands form the perpendicular plane. The imine is disposed trans to the chlorine and cis to the water molecule. The angles ClOs-N [158.55(18)°] and N-Os-O(4) [78.3(2)°] largely deviate from the ideal values of 180° and 90°, respectively, suggesting that in this case there is an intramolecular O‚‚‚H-N hydrogen bond between the water



Table 3. Crystal Data and Data Collection and Refinement for OsCl2(dCdCHPh)(NHdCMe2)(PiPr3)2 (7) and [OsCl(dCdCHPh)(NHdCMe2)(H2O)(PiPr3)2][CF3SO3]‚C4H8O (9) formula mol wt color, habit space group a, Å b, Å c, Å R, deg β, deg γ, deg V, Å3 Z Dcalc, g cm-3 diffractometer STOE AED-2 λ(Mo KR), Å monochromator µ, mm-1 scan type 2θ range, deg temp, K no.of data collect no. of unique data no. of params refined R1a [F2 > 2σ(F2)] wR2b [all data] Sc [all data]

7 C29H55Cl2NOsP2 740.78 orange, prismatic triclinic, P1 h 9.065(3) 11.840(4) 16.591(6) 84.93(2) 85.69(2) 69.77(3) 1662.4(10) 2 1.480

9 C30H57ClF3NO4OsP2S × C4H8O 944.52 red, prismatic triclinic, P1 h 10.788(1) 12.853(2) 15.889(2) 92.554(10) 92.073(14) 109.733(8) 2068.6(4) 42 1.516

Data Collection and Refinement Brucker-Siemens

Bruker Siemens-P4

0.71073 graphite oriented 4.11

3.33 ω/2θ

5° e 2θ e 50° 298.0(2) 8044 (h: -10, 3; k: -14, 13; l: -19, 19) 5845 (merging R factor 0.0724) 336 0.0462 0.0886 1.010

5° e 2θ e 50° 173.0(2) 7851 (h: -12, 1; k: -14, 15; l: -18, 18) 6226 (merging R factor 0.0323) 525 0.0426 0.1077 1.033

a R (F) ) ∑||F | - |F ||/∑|F |. b wR (F2) ) {∑[w(F 2 - F 2)2/∑[w|F 2)2]}1/2. c Goof ) S ) {σ[w(F 2 - F 2)2]/(n - p)}1/2, where n is the 1 o c o 2 o c o o c number of reflections, and p is the number of refined parameters.

molecule and the N-H hydrogen atom of the imine. In agreement with this, the separation between the atoms involved in the hydrogen bond (about 2.36 Å) is shorter than the sum of the van der Waals radii of hydrogen and oxygen [rvdw(O) ) 1.40 Å]. The O‚‚‚H interaction gives rise to a four-membered Os-O‚‚‚H-N ring, which is almost planar with the plane containing the Os, Cl, O(4), N, and C(1) atoms. The dihedral angle between this plane and that containing the N, C(9), C(10), and C(11) atoms is 9.4°.36 The vinylidene ligand is bound to the metal in a nearly linear fashion with an Os-C(1)-C(2) angle of 176.5(6)°, while the imine is bound to the metal in a bent fashion with an Os-N-C(9) angle of 142.7(6)°. The Os-C(1) [1.803(7) Å], C(1)-C(2) [1.344(10) Å], Os-N [2.067(5) Å], and N-C(9) [1.290(10) Å] distances are similar to the related parameters previously mentioned for 7. Complexes 9 and 10 are stable for long times if kept as solids under argon at -20 °C. In solution of dichloromethane they are stable at temperatures lower than -20 °C. At room temperature, they rapidly evolve to give ill-defined straw-colored solids. In the 1H NMR spectra of 9 and 10 in dichloromethane-d2 at -60 °C, the most noticeable features are three broad resonances at about 10.5, 5.5, and 2.4 ppm corresponding to the N-H, OH2, and CdCHPh protons, respectively. In the 13C{1H} NMR spectra at (36) Complex 9 crystallizes with a tetrahydrofuran molecule. A careful analysis of intermolecular distances and angles suggests intermolecular interactions between the hydrogen atoms of the water and imine ligands and the oxygen atoms of the tetrahydrofuran and triflate.

-30 °C, the resonances corresponding to the CR atoms of the vinylidene ligands appear at about 299 ppm as triplets with C-P coupling constants at about 11 Hz, whereas the resonances due to the Cβ atoms are observed at about 112 ppm as singlets. The CdN carbon atoms of the imine groups give rise to singlets between 190 and 185 ppm. The 31P{1H} NMR spectra contain singlets at -15.3 (9) and -15.0 (10) ppm. The formation of 9 and 10 involves the initial coordination of water to the metallic centers of 3 and 4 to give the alkenyl-azavinylidene intermediates [Os{(E)CHdCHPh}Cl(dNdCR2)(H2O)(PiPr3)2][CF3SO3] (CR2 ) CMe2 (11), C(CH2)4CH2 (12)], which at -30 °C afford 9 and 10 before the transformations of 3 and 4 into 11 and 12 are complete. These intermediates were characterized in solution at -90 °C by 1H and 31P{1H} NMR spectroscopy. In the 1H NMR spectra in dichloromethaned2, the most noticeable resonances are two doublets at about 11 and 5 ppm, with H-H coupling constants of about 16 Hz, corresponding to the vinylic protons of the alkenyl ligands, and a broad signal at about 5.5 ppm, due to the protons of the coordinated water molecule. The 31P{1H} NMR spectra contain singlets at about -36 ppm, indicating that the phosphine ligands in the intermediates are mutually trans disposed, as in the starting compounds and in the reaction products. The stability of cationic imine-vinylidene complexes of formula [OsCl(dCdCHPh)(NHdCR2)L(PiPr3)2][CF3SO3] is highly dependent upon the nature of the L ligands. Thus, in contrast with 9 and 10, the related acetonitrile derivatives [OsCl(dCdCHPh)(NHdCR2)(CH3CN)(PiPr3)2][CF3SO3] [CR2 ) CMe2 (13), C(CH2)4CH2

5460


(14)] are stable at room temperature in the solid state and in solution of dichloromethane. Complexes 13 and 14 have been obtained as brown solids in about 60% yield, by stirring of 3 and 4 in acetonitrile at room temperature, according to eq 2.

Castarlenas et al.

compounds, species containing both functional groups were unknown until now. This paper reports the formation of the neutral imine-vinylidene derivatives OsCl2(dCdCHPh}(NHdCR2)(PiPr3)2 [CR2 ) CMe2, C(CH2)4CH2] and the cationic imine-vinylidene derivatives [OsCl(dCdCHPh}(NHdCR2)L(PiPr3)2][CF3SO3] [L ) H2O, CH3CN; CR2 ) CMe2, C(CH2)4CH2]. These compounds are formed by a novel reaction, the hydrogen transfer from alkenyl ligands to azavinylidene groups. The reaction takes place in another class of interesting organometallic complexes, six-coordinate neutral and cationic alkenyl-azavinylidene-osmium(IV) intermediates of the types Os{(E)-CHdCHPh}Cl2(dNdCR2)(PiPr3)2 and [Os{(E)-CHdCHPh}Cl(dNdCR2)L(PiPr ) ][CF SO ] [L ) H O, CH CN; CR 3 2 3 3 2 3 2 ) CMe2,

In the 1H NMR spectra of 13 and 14 in acetone-d6 at room temperature, the most noticeable features are broad resonances at about 10 ppm corresponding to the NH hydrogen atoms of the imines, singlets at about 3 ppm due to the CH3 groups of the acetonitrile ligands, and triplets at about 2.5 ppm with H-P coupling constants of about 2 Hz corresponding to the dCH hydrogen atoms of the vinylidene ligands. In the 13C{1H} NMR spectra, the resonances due to the CR atoms of the vinylidenes appear at 304.6 (13) and 307.4 (14) ppm as triplets with C-P coupling constants of about 9 Hz, while the Cβ atoms display singlets at 111.6 (13) and 114.6 (14) ppm. The CdN carbon atoms of the imines give rise to singlets at 185.7 (13) and 192.2 (14) ppm. The 31P{1H} NMR spectra show singlets at -10.2 (13) and -7.8 (14) ppm. Complexes 13 and 14 are formed in a manner similar to 9 and 10, by hydrogen transfer from the styryl ligand to the azavinylidene groups in cationic six-coordinate styryl-azavinylidene intermediates. In fact, the addition at -20 °C of 1.2 equiv of acetonitrile to dichloromethane solutions of 3 and 4 initially gives [Os{(E)CHdCHPh}Cl(dNdCR2)(CH3CN)(PiPr3)2][CF3SO3] (CR2 ) CMe2 (15), C(CH2)4CH2 (16)], which at room temperature evolve into 13 and 14. These intermediates were characterized in solution at -20 °C by 1H, 13C{1H}, and 31P{1H} NMR spectroscopy. In the 1H NMR spectra in dichlorometane-d2, the most noticeable resonances are two doublets at about 11 and 5 ppm, with H-H coupling constants of about 16 Hz, corresponding to the vinylic protons of the styryl ligands, and a singlet at about 3.5 ppm due to the CH3 protons of the acetonitrile groups. In the 13C{1H} NMR spectra the resonances due to the vinylic carbon atoms of the styryl ligands appear at about 138 (CR) and 123 (Cβ). The CdN carbon atoms of the azavinyilidene groups are observed at 155.8 (15) and 156.3 (16). The 31P{1H} NMR spectra contain singlets at about -32 ppm. Concluding Remarks Although imine and vinylidene transition metal complexes are two interesting types of organometellic

C(CH2)4CH2], which have also been characterized. Complexes OsCl2(dCdCHPh}(NHdCR2)(PiPr3)2 and [OsCl(dCdCHPh}(NHdCR2)(H2O)(PiPr3)2][CF3SO3] are octahedral with the imine groups situated cis to the chlorine ligand and the water molecule, respectively. As a consequence of the high electronegativity of the chlorine and oxygen atoms, this disposition gives rise to intramolecular Cl‚‚‚H-N and O‚‚‚H-N hydrogen bonds, between the N-H hydrogen atoms of the imines and the chlorine ligand or water molecule. These interactions are manifested by short Cl‚‚‚H (2.366 Å) and O‚‚‚H (2.36 Å) separations and Cl-Os-N [77.34(18)°] and N-Os-O [78.3(2)°] angles largely deviated from the ideal value of 90° for a cis arrangement. In conclusion, this study has revealed the existence of imine-vinylidene compounds, two new examples of N-H‚‚‚X (Cl, O) hydrogen bonds, and the novel hydrogen transfer reaction from alkenyl ligands to azavinylidene groups. Experimental Section All reactions were carried out with rigorous exclusion of air using Schlenk-tube techniques. Solvents were dried by the usual procedures and distilled under argon prior to use. The starting materials OsHCl2{dNdC(CH3)2}(PiPr3)2 (1) and OsHCl2{dNdC(CH2)4CH2}(PiPr3)2 (2) were prepared by the published method.23 1H NMR spectra were recorded at 300 MHz, and chemical shifts are expressed in ppm downfield from Me4Si. 13C{1H} spectra were recorded at 75.4 MHz, and chemical shifts are expressed in ppm downfield from Me4Si. 31P{1H}spectra were recorded at 121.4 MHz, and chemical shifts are expressed in ppm downfield from 85% H3PO4. Coupling constants, J and N, are given in hertz. Preparation of [Os{(E)-CHdCHPh}Cl{dNdC(CH3)2}(PiPr3)2][CF3SO3] (3). A blue-green solution of 1 (100 mg, 0.157 mmol) in a mixture of dichloromethane (10 mL) and acetone (0.5 mL) was treated with 40 mg (0.157 mmol) of Ag[CF3SO3]. The suspension was stirred for 3 h and was filtered through Celite to eliminate the AgCl formed. The blue solution was cooled to -25 °C, and 20 µL (0.196 mmol) of phenylacetylene was added. The reaction was stirred for 5 h at a temperature between -25 and -10 °C. The color changed to green, and the solvent was concentrated to dryness keeping the temperature lower than -10 °C. Addition of diethyl ether at -50 °C yielded a green precipitate that was washed three times with cold diethyl ether and dried in vacuo. Yield: 95 mg (71%). Anal. Calcd for C30H55NSClF3O3OsP2: C, 42.17; H, 6.48; N, 1.63; S, 3.74. Found: C, 41.83; H, 6.41; N, 1.58; S 3.77. IR (KBr, cm-1): ν(CdN) 1624 (m); νa(SO3) 1274 (s); νs-

Imine-Vinylidene-Osmium(II) Derivatives (CF3) 1236 (s); νa(CF3) 1160 (s); νs(SO3) 1031 (s); δa(SO3) 638 (s). 1H NMR (CD2Cl2, 20 °C): δ 7.81 (d, JH-H ) 11.7, 1H, OsCHdCHPh); 7.41 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.96 (t, JH-H ) 7.2, 1H, Hpara-Ph); 6.86 (d, JH-H ) 7.5, 2H, Hortho-Ph); 4.00 (br, 6H, {CH3}2CdN); 3.92 (dt, JH-H ) 11.7, JH-P ) 10.2, 1H, OsCHdCHPh); 2.82 (m, 6H, PCH); 1.37 and 1.35 (both dvt, JH-H ) 6.9, N ) 13.8, 36H, PCHCH3). 13C{1H} NMR plus APT (CD2Cl2, -40 °C): δ 160.6 (br, OsdNdC); 144.0 (t, JC-P ) 6.0, OsCHdCHPh); 137.5 (br, Os-CHdCHPh); 134.1 (s, Cipso-Ph); 127.8, 127.6 and 126.8 (all s, CPh); 120.4 (c, JC-F ) 320.0, CF3); 23.3 (vt, N ) 22.0, PCH); 19.0 and 18.8 (both s, PCHCH3); 10.6 and 8.0 (both s, {CH3}2CdN). 31P{1H} NMR (CD2Cl2, 20 °C): δ 0.1 (s). MS (FAB+): m/z ) 705 (M+). Preparationof[Os{(E)-CHdCHPh}Cl{dNdC(CH2)4CH2}(PiPr3)2][CF3SO3] (4). This complex was prepared as described for 3 starting from 100 mg (0.147 mmol) of 2, 37 mg (0.147 mmol) of Ag[CF3SO3], and 20 µL (0.196 mmol) of phenylacetylene. Yield: 92 mg (70%). Anal. Calcd for C33H59NSClF3O3OsP2: C, 44.31; H, 6.64; N, 1.56; S, 3.57. Found: C, 43.98; H, 6.53; N, 1.48; S 3.21. IR (KBr, cm-1): ν(CdN) 1617 (m); νa(SO3) 1271 (s); νs(CF3) 1235 (s); νa(CF3) 1159 (s); νs(SO3) 1030 (s); δa(SO3) 637 (s). 1H NMR (CD2Cl2, 20 °C): δ 7.84 (d, JH-H ) 10.8, 1H, Os-CHdCHPh); 7.39 (t, JH-H ) 7.2, 2H, Hmeta-Ph); 6.96 (t, JH-H ) 7.2, 1H, Hpara-Ph); 6.83 (d, JH-H ) 7.5, 2H, Hortho-Ph); 4.30 (br, 4H, {CH2}2CdN); 3.92 (br, OsCHdCHPh); 2.84 (m, 6H, PCH); 1.8-1.5 (m, 6H, Cy); 1.37 and 1.35 (both dvt, JH-H ) 6.9, N ) 13.8, 36H, PCHCH3). 13C{1H} NMR (CD2Cl2, -40 °C): δ 161.9 (br, OsdNdC); 143.6 (t, JC-P ) 5.0, Os-CHdCHPh); 137.5 (br, Os-CHdCHPh); 134.2 (s, Cipso-Ph); 128.9, 127.8 and 126.8 (all s, CPh); 120.3 (c, JC-F ) 319.7, CF3); 36.1 and 33.8 (both s, {CH2}2CdN); 24.4, 21.6 and 18.3 (all s, CH2 Cy); 22.7 (vt, N ) 24.0, PCH); 19.0 and 18.7 (both s, PCHCH3). 31P{1H} NMR (CD2Cl2, 20 °C): δ 2.1 (s). MS (FAB+): m/z ) 746 (M+). Preparation of Os{(E)-CHdCHPh}Cl2{dNdC(CH3)2}(PiPr3)2 (5). A green solution of 3 (100 mg, 0.117 mmol), in 8 mL of THF at -30 °C, was treated with NaCl (25 mg, 0.428 mmol) and was kept stirring for 3 h at this temperature. The color changed to orange, and the solvent was concentrated to dryness at -30 °C. Then 8 mL of toluene was added to eliminate by filtration the NaSO3CF3 formed and the excess of NaCl. After the toluene was removed again at -30 °C, addition of pentane at -50 °C yielded an orange precipitate, which was washed three times with cold pentane and dried in vacuo. Yield: 70 mg (80%). Anal. Calcd for C29H55NCl2OsP2: C, 47.02; H, 7.48; N, 1.89. Found: C, 46.74; H, 7.48; N, 1.75. IR (KBr, cm-1): ν(CdN) 1667 (m). 1H NMR (C6D6, 20 °C): δ 11.97 (d, JH-H ) 16.5, 1H, Os-CHdCHPh); 7.32 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 7.04 (d, JH-H ) 7.8, 2H, Hortho-Ph); 6.70 (t, JH-H ) 7.5, 1H, Hpara-Ph); 4.93 (d, JH-H ) 16.5, 1H, Os-CHd CHPh); 3.90 (br, 6H, {CH3}2CdN); 2.91 (m, 6H, PCH); 1.32 and 1.28 (both dvt, JH-H ) 6.5, N ) 12.3, 36H, PCHCH3). 13C{1H} NMR (CDCl3, 20 °C): δ 150.7 (s, OsdNdC); 139.4 (s, OsCHdCHPh); 133.4 (JC-P ) 3.5, Os-CHdCHPh); 129.0 (s, Cipso-Ph); 128.2, 127.3 and 127.0 (all s, CPh); 23.7 (vt, N ) 22.0, PCH); 19.2 and 19.1 (both s, PCHCH3); 17.8 (br, {CH3}2Cd N). 31P{1H} NMR (C6D6, 20 °C): δ -51.4 (s). MS (FAB+): m/z ) 706 (M+ - Cl). PreparationofOsCl2{(E)-CHdCHPh}{dNdC(CH2)4CH2}(PiPr3)2 (6). This complex was prepared as described for 5 starting from 125 mg (0.140 mmol) of 4 and NaCl (25 mg, 0.428 mmol). Yield: 90 mg (82%). Anal. Calcd for C32H59NCl2OsP2: C, 49.22; H, 7.62; N, 1.79. Found: C, 49.64; H, 7.50; N, 1.86. IR (KBr, cm-1): ν(CdN) 1656 (m). 1H NMR (C6D6, 20 °C): δ 11.62 (d, JH-H ) 16.0, 1H, Os-CHdCHPh); 7.35 (t, JH-H ) 7.2, 2H, Hmeta-Ph); 6.85 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.73 (t, JH-H ) 7.2, 1H, Hpara-Ph); 4.80 (d, JH-H ) 16.8, 1H, Os-CHd CHPh); 4.6 (br, 4H, {CH2}2CdN); 3.01 (m, 6H, PCH); 1.8-1.5 (m, 6H, Cy); 1.44 and 1.39 (both dvt, JH-H ) 6.5, N ) 13.2, 36H, PCHCH3). 13C{1H} NMR plus APT (CDCl3, 20 °C): δ

Organometallics, Vol. 19, No. 25, 2000 5461 152.6 (s, OsdNdC); 138.9 (t, JC-P ) 2.8, Os CHdCHPh); 138.7 (s, Cipso-Ph); 137.5 (s, Os CHdCHPh); 128.9, 127.8 and 126.8 (all s, CPh); 120.3 (c, JC-F ) 319.7., CF3); 27.6 (br, {CH2}2Cd N); 25.5 and 24.0 (both s, CH2 Cy) 23.3 (vt, N ) 23.5, PCH); 19.0 and 18.7 (both s, PCHCH3). 31P{1H} NMR (C6D6, 20 °C): δ -49.6 (s). MS (FAB+): m/z ) 746 (M+). Preparation of OsCl2(dCdCHPh){NHdC(CH3)2}(PiPr3)2 (7). A green solution of 3 (100 mg, 0.117 mmol) in a mixture of THF (10 mL) and methanol (2 mL) was treated with NaCl (25 mg, 0.428 mmol) and was kept stirring for 3 h at room temperature. Then the solvent was removed and dichloromethane (10 mL) was added to filter the ionic salts. The resulting orange solution was evaporated to dryness, and addition of methanol (2 mL) yielded an orange solid, which was washed with methanol (2 × 2 mL) and pentane (3 × 3 mL) and dried in vacuo. Yield: 70 mg (80%). Anal. Calcd for C29H55NCl2OsP2: C, 47.02; H, 7.48; N, 1.89. Found: C, 47.03; H, 7.45; N, 2.02. IR (KBr, cm-1): ν(N-H) 3216 (m); ν(CdN) 1661 (s); ν(OsdCdC) 1611 (s). 1H NMR (C6D6, 20 °C): δ 11.30 (br, 1H, N-H); 7.40 (d, JH-H ) 7.5, 2H, Hortho-Ph); 7.30 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.80 (t, JH-H ) 7.5, 1H, Hpara-Ph); 2.86 (m, 6H, PCH); 1.98 (t, JH-P ) 1.5, 1H, OsdCdCHPh); 1.67 and 1.48 (both s, 6H, {CH3}2CdN); 1.35 and 1.30 (both dvt, JH-H ) 6.6, N ) 13.2, 36H, PCHCH3). 13C{1H}-APT NMR (C6D6, 20 °C): δ 295.3 (t, JC-P ) 10.0, OsdC); 177.0 (s, CdN); 131.0 (s, Cipso-Ph); 127.3, 126.2 and 123.7 (all s, CPh); 113.9 (t, JC-P ) 3.2, OsdCdC); 30.0 and 24.8 (both s, {CH3}2CdN); 23.8 (vt, N ) 22.0, PCH); 19.8 and 19.6 (both s, PCHCH3). 31P{1H} NMR (C6D6, 20 °C): δ -21.1 (s). MS (FAB+): m/z ) 705 (M+ - HCl). Preparation of OsCl2(dCdCHPh){NHdC(CH2)4CH2}(PiPr3)2 (8). This complex was prepared as described for 7 starting from 125 mg (0.140 mmol) of 4 and 25 mg (0.428 mmol) of NaCl. Yield: 85 mg (78%). Anal. Calcd for C32H59NCl2OsP2: C, 49.22; H, 7.62; N, 1.79. Found: C, 49.04; H, 7.54; N, 1.72. IR (KBr, cm-1): ν(N-H) 3202 (m); ν(CdN) 1656 (m); ν(OsdCdC) 1610 (s). 1H NMR (C6D6, 20 °C): δ 11.07 (br, 1H, N-H); 7.09 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.94 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.67 (t, JH-H ) 7.5, 1H, Hpara-Ph); 2.78 (m, 6H, PCH); 2.59 and 2.48 (both m, 4H, {CH2}2CdN); 1.82 (t, JH-P ) 2.0, 1H, OsdCdCHPh); 1.71 (m, 2H, Cy); 1.58 (m, 4H, Cy); 1.31 and 1.27 (both dvt, JH-H ) 6.9, N ) 12.9, 36H, PCHCH3). 13C{1H}-APT NMR (C D , 20 °C): δ 295.1 (t, J 6 6 C-P ) 8.3, Osd C); 182.7 (s, CdN); 130.2 (s, Cipso-Ph); 127.3, 125.7, and 122.8 (all s, CPh); 113.3 (t, JC-P ) 3.7, OsdCdC); 42.9, 34.4, 26.2, 25.5, and 24.2 (all s, CH2 Cy); 23.4 (vt, N ) 22.1, PCH); 19.6 and 19.4 (both s, PCHCH3). 31P{1H} NMR (C6D6, 20 °C): δ -20.8 (s). MS (FAB+): m/z ) 745 (M+ - HCl). Preparation of [OsCl(dCdCHPh){NHdC(CH3)2}(H2O)(PiPr3)2][CF3SO3] (9). A green solution of 3 (125 mg, 0.146 mmol) in THF (10 mL) at -20 °C was treated with H2O (25 µL, 1.39 mmol) and was kept in the freezer at -20 °C for 3 days. The color changed to red, and after the solvent was removed at -20 °C, addition of cold diethyl ether yielded a mycrocristalline red solid, which was washed with diethyl ether (3 × 2 mL) and dried in vacuo. Yield: 90 mg (70%). Anal. Calcd for C30H57NSClF3O4OsP2: C, 41.30; H, 5.59; N, 1.61; S, 3.67. Found: C, 41.12; H, 5.34; N, 1.72; S, 3.72. IR (KBr, cm-1): ν(H2O) 3254 (br); ν(N-H) overlapped by H2O; ν(CdN) 1662 (s); ν(OsdCdC) 1617 (s); νa(SO3) 1297 (s); νs(CF3) 1234 (s); νa(CF3) 1167 (s); νs(SO3) 1028 (s); δa(SO3) 639 (s). 1H NMR (CD2Cl2, -60 °C): δ 10.42 (br, 1H, N-H); 7.15 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.86 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.74 (t, JH-H ) 7.5, 1H, Hpara-Ph); 5.45 (br, 2H, H2O); 2.59 (m, 6H, PCH); 2.57 and 2.25 (both s, 6H, {CH3}2CdN); 2.45 (br, 1H, OsdCd CHPh); 1.4-1.2 (br, 36H, PCHCH3). 13C{1H} NMR (CD2Cl2, -30 °C): δ 299.0 (t, JC-P ) 10.6, OsdC); 185.2 (s, CdN); 129.0, 127.3, 125.1, and 123.5 (all s, CPh); 120.1 (c, JC-F ) 316.6, CF3); 112.6 (s, OsdCdC); 28.8 and 27.1 (both s, {CH3}2CdN); 23.5

5462


(br, PCH); 19.2 and 18.6 (both s, PCHCH3). 31P{1H} NMR (CD2Cl2, -60 °C): δ -15.3 (s). MS (FAB+): m/z ) 705 (M+ - H2O). Preparation of [OsCl2(dCdCHPh){NHdC(CH2)4CH2}(H2O)(PiPr3)2][CF3SO3] (10). This complex was prepared as described for 9 starting from 125 mg (0.140 mmol) of 4 and 25 µL of H2O (1.39 mmol). Yield: 95 mg (74%). Anal. Calcd for C33H61NSClF3O4OsP2: C, 43.43; H, 6.74; N, 1.53. Found: C, 43.14; H, 6.42; N, 1.59. IR (KBr, cm-1): ν(H2O) 3237 (br); ν(N-H) overlapped by the ν(H2O); ν(CdN) 1655 (s); ν(OsdCd C) 1617 (s); νa(SO3) 1302 (s); νs(CF3) 1237 (s); νa(CF3) 1164 (s); νs(SO3) 1029 (s); δa(SO3) 638 (s). 1H NMR (CD2Cl2, -40 °C): δ 10.30 (br, 1H, N-H); 7.13 (t, JH-H ) 7.2, 2H, Hmeta-Ph); 6.87 (d, JH-H ) 7.2, 2H, Hortho-Ph); 6.72 (t, JH-H ) 7.2, 1H, Hpara-Ph); 5.30 (br, 2H, H2O); 2.42 (br, 1H, OsdCdCHPh); 2.84 and 2.38 (both m, 4H, {CH2}2CdN); 2.60 (m, 6H, PCH); 1.73 (m, 2H, Cy); 1.60 (m, 4H, Cy); 1.28 (br, 36H, PCHCH3). 13C{1H} NMR (CD2Cl2, -40 °C): δ 299.1 (t, JC-P ) 10.5, OsdC); 190.0 (s, CdN); 129.1, 127.4, 125.0, and 122.0 (all s, CPh); 112.6 (s, Osd CdC); 40.4, 35.4, 26.4, 26.1, and 24.1 (all s, Cy); 24.1 (br, PCH); 20-18 (br, PCHCH3). 31P{1H} NMR (CD2Cl2, -40 °C): δ -15.0 (s). MS (FAB+): m/z ) 746 (M+ - H2O). Reaction of 3 with H2O: Preparation of [Os{(E)-CHd CHPh}Cl{dNdC(CH3)2}(H2O)(PiPr3)2][CF3SO3] (11). A solution of 3 (25 mg, 0.029 mmol) in 0.5 mL of dichloromethaned2 in an NMR tube at -90 °C was treated with H2O (1 µL, 0.055 mmol). The NMR tube was sealed under argon, and measurements were made immediately. 1H NMR (CD2Cl2, -90 °C): δ 10.65 (d, JH-H ) 15.6, 1H, Os-CHdCHPh); 7.30 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.94 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.84 (t, JH-H ) 7.5, 1H, Hpara-Ph); 5.63 (br, 2H, H2O); 4.72 (d, JH-H ) 15.6, 1H, Os-CHdCHPh); 3.88 and 3.82 (both s, 6H, {CH3}2Cd N); 2.51 (m, 6H, PCH); 1.21 (br, 36H, PCHCH3). 31P{1H} NMR (CD2Cl2, -90 °C): δ -36.0 (s). Reaction of 4 with H2O: Preparation of [Os{(E)-CHd CHPh}Cl{dNdC(CH2)4CH2}(H2O)(PiPr3)2][CF3SO3] (12). This complex was prepared as described for 11 starting from 25 mg (0.028 mmol) of 4 and 1 µL (0.055 mmol) of H2O. 1H NMR (CD2Cl2, -90 °C): δ 10.70 (d, JH-H ) 15.9, 1H, Os-CHd CHPh); 7.37 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 7.02 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.90 (t, JH-H ) 7.5, 1H, Hpara-Ph); 5.71 (br, 2H, H2O); 4.81 (d, JH-H ) 15.9, 1H, Os-CHdCHPh); 3.9-3.7 (m, 4H, {CH2}2CdN); 2.77 (m, 6H, PCH); 2-1 (m, 6H, Cy); 1.29 (br, 36H, PCHCH3). 31P{1H} NMR (CD2Cl2, -90 °C): δ -35.6 (s). Preparationof[OsCl(dCdCHPh){NHdC(CH3)2}(NCCH3)(PiPr3)2][CF3SO3] (13). A green solution of 3 (125 mg, 0.146 mmol) in CH3CN (10 mL) was stirred for 4 h at room temperature. The color changed to brown. The solvent was concentrated to ca. 1 mL, and addition of diethyl ether yielded a brown precipitate, which was decanted, washed twice with diethyl ether, and dried in vacuo. Yield: 80 mg (61%). Anal. Calcd for C32H58N2SClF3O3OsP2: C, 42.92; H, 6.53; N, 3.13; S, 3.58. Found: C, 42.81; H, 6.37; N, 3.22; S, 3.41. IR (KBr, cm-1): ν(N-H) 3240 (br); ν(CtN) 2301 (w); ν(CdN) 1687 (s); ν(OsdCdC) 1618 (s); νa(SO3) 1260 (s); νs(CF3) 1223 (s); νa(CF3) 1154 (s); νs(SO3) 1031 (s); δa(SO3) 638 (s). 1H NMR (acetoned6, 20 °C): δ 10.17 (br, 1H, N-H); 7.30 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 7.00 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.90 (t, JH-H ) 7.5, 1H, Hpara-Ph); 3.22 (s, 3H, NCCH3); 2.81 (m, 6H, PCH); 2.65 and 2.52 (both s, 6H, {CH3}2CdN); 2.62 (t, JH-P ) 2.4, 1H, OsdCdCHPh); 1.37 and 1.35 (both dvt, JH-H ) 6.9, N ) 13.5, 36H, PCHCH3). 13C{1H}-APT NMR (acetone-d6, 20 °C): δ 304.6 (t, JC-P ) 9.2, OsdC); 185.7 (s, CdN); 130.7 (s, Cipso-Ph); 126.7, 125.4 and 123.6 (all s, CPh); 125.1 (s, NtC-CH3); 121.1 (c, JC-F ) 316.6, CF3); 111.6 (s, OsdCdC); 29.1 and 24.1 (both s, {CH3}2CdN); 22.0 (vt, N ) 23.3, PCH); 17.5 and 17.2 (both s, PCHCH3); 1.9 (s, NtC-CH3). 31P{1H} NMR (acetone-d6, 20 °C): δ -10.2 (s). MS (FAB+): m/z ) 706 (M+ - NCCH3).

Castarlenas et al. Preparation of [OsCl(dCdCHPh){NHdC(CH2)4CH2}(NCCH3)(PiPr3)2][CF3SO3] (14). This complex was prepared as described for 13 starting from 125 mg (0.140 mmol) of 4. Yield: 85 mg (64%). Anal. Calcd for C35H62N2SClF3O3OsP2: C, 44.94; H, 6.68; N, 2.99; S, 3.43. Found: C, 44.75; H, 6.55; N, 2.82; S, 3.31. IR (KBr, cm-1): ν(N-H) 3246 (br); ν(CtN) 2303 (w); ν(CdN) 1686 (s); ν(OsdCdC) 1626 (s); νa(SO3) 1261 (s); νs(CF3) 1223 (s); νa(CF3) 1149 (s); νs(SO3) 1031 (s); δa(SO3) 637 (s). 1H NMR (acetone-d6, 20 °C): δ 10.18 (br, 1H, N-H); 7.31 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.99 (d, JH-H ) 7.2, 2H, Hortho-Ph); 6.92 (t, JH-H ) 7.5, 1H, Hpara-Ph); 3.24 (s, 3H, NCCH3); 2.91 and 2.81 (both m, 4H, {CH2}2CdN); 2.79 (m, 6H, PCH); 2.63 (t, JH-P ) 2.0, 1H, OsdCdCHPh); 1.86 (m, 2H, Cy); 1.72 (m, 4H, Cy); 1.34 and 1.32 (both dvt, JH-H ) 6.9, N ) 13.5, 36H, PCHCH3). 13C{1H}-APT NMR (acetone-d6, 20 °C): δ 307.4 (t, JC-P ) 9.1, OsdC); 192.2 (s, CdN); 136.6 (s, Cipso-Ph); 129.5, 128.2, and 126.2 (all s, CPh); 127.9 (s, NtC-CH3); 114.6 (s, OsdCdC); 43.4, 36.4, 27.6, 27.1, and 25.0 (all s, CH2 Cy); 24.9 (vt, N ) 23.4, PCH); 20.5 and 19.7 (both s, PCHCH3); 8.8 (s, N/CtCH3). 31P{1H} NMR (acetone-d6, 20 °C): δ -7.8 (s). MS (FAB+): m/z ) 787 (M+); 746 (M+ - NCCH3). Reaction of 3 with CH3CN: Preparation of [Os{(E)CHdCHPh}Cl{dNdC(CH3)2}(NCCH3)(PiPr3)2][CF3SO3] (15). A solution of 3 (25 mg, 0.029 mmol) in 0.5 mL of dichloromethane-d2 in a NMR tube at -20 °C was treated with CH3CN (2 µL, 0.035 mmol). The NMR tube was sealed under argon, and measurements were made immediately. 1H NMR (CD2Cl2, -20 °C): δ 10.93 (d, JH-H ) 16.0, 1H, Os-CHd CHPh); 7.38 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 7.08 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.88 (t, JH-H ) 7.5, 1H, Hpara-Ph); 5.22 (d, JH-H ) 16.0, 1H, Os-CHdCHPh); 3.63 and 3.56 (both s, 6H, {CH3}2CdN); 3.44 (s, 3H, NCCH3); 2.86 (m, 6H, PCH); 1.40 (br, 36H, PCHCH3). 13C{1H} NMR (CD2Cl2, -20 °C): δ 155.9 (s, CdN); 138.2 (s, NtC-CH3); 137.9 (s, Os-CHdCHPh); 137.2 (s, Cipso-Ph); 127.8, 127.4, and 127.0 (all s, CPh); 123.1 (s, Os-CHdCHPh); 121.1 (c, JC-F ) 318.2, CF3); 22.0 (vt, N ) 23.0, PCH); 19.0 and 18.7 (both s, PCHCH3); 5.7 (s, NtCCH3); 4.2 and 3.9 (both s, ({CH3}2CdN). 31P{1H} NMR (CD2Cl2, -20 °C): δ -36.4 (s). Reaction of 4 with CH3CN: Preparation of Os{(E)CHdCHPh}Cl{dNdC(CH2)4CH2}(NCCH3)(PiPr3)2][CF3SO3] (16). This complex was prepared as described for 15 starting from 25 mg (0.028 mmol) of 4 and CH3CN (2 µL, 0.035 mmol). 1H NMR (CD2Cl2, -20 °C): δ 10.72 (d, JH-H ) 15.9, 1H, Os-CHdCHPh); 7.35 (t, JH-H ) 7.5, 2H, Hmeta-Ph); 6.95 (d, JH-H ) 7.5, 2H, Hortho-Ph); 6.88 (t, JH-H ) 7.5, 1H, Hpara-Ph); 5.04 (d, JH-H ) 15.9, 1H, Os-CHdCHPh); 3.64 and 3.57 (both s, 4H, {CH2}2CdN); 3.16 (s, 3H, NCCH3); 2.73 (m, 6H, PCH); 2-1 (m, 6H, Cy); 1.35 (br, 36H, PCHCH3). 13C{1H} NMR (CD2Cl2, -20 °C): δ 156.3 (s, CdN); 138.2 (s, Os-CHdCHPh); 137.5 (s, Cipso-Ph); 135.3 (s, NtC-CH3); 127.5, 127.0, and 126.9 (all s, CPh); 123.3 (s, Os-CHdCHPh); 121.1 (c, JC-F ) 318.2, CF3); 26.2, 26.0, 16.5, 14.7 (all s, Cy); 22.9 (vt, N ) 23.0, PCH); 18.8 and 18.7 (both s, PCHCH3); 4.9 (s, NtC-CH3). 31P{1H} NMR (CD2Cl2, -20 °C): δ -36.6 (s). Crystal Data for OsCl2(dCdCHPh){NHdC(CH3)2}(PiPr3)2 (7) and [OsCl(dCdCHPh){NHdC(CH3)2}(H2O)(PiPr3)2][CF3SO3] (9). Crystals suitable for X-ray diffraction analysis were mounted onto a glass fiber and transferred to an Bruker-Siemens-STOE AED-2 (7, T ) 298.0(2) K) and Bruker-Siemens P-4 (9, T ) 173.0(2) K) automatic diffractometers (Mo KR radiation, graphite monocromator, λ ) 0.71073 Å). Accurate unit cell parameters were determined by leastsquares fitting from the settings of high-angle reflections. Data were collected by the ω/2θ scan method. Lorentz and polarization corrections were applied. Decay was monitored by measuring three standards throughout data collection. Corrections for decay and absortion (semiempirical ψ-scan method) were also applied.

Imine-Vinylidene-Osmium(II) Derivatives The structures were solved by Patterson methods and refined by full matrix least-squares on F2 (7 and 9).37 For 7, non hydrogen atoms were anisotropically refined, and the hydrogen atoms were observed or included at idealized positions. The imine and vinylidene hydrogen atoms H(01) and H(5) were located in the difference Fourier maps and refined isotropically. For 9, the triflate anion and the THF solvent molecules were observed disordered. Both molecules were refined with two moieties, complementary occupancy factors, isotropic atoms, and restrained geometry.37 The rest of the nonhydrogen atoms were anisotropically refined, and hydrogen atoms were observed or included at idealized positions. In this case, only the water hydrogen atoms could be refined freely as isotropic atoms. (37) Sheldrick, G. M. SHELX-97; Go¨ttingen, 1997.


Acknowledgment. Financial support from the DGES of Spain (Project PB98-1591) is acknowledged. R.C. thanks the “Ministerio de Ciencia y Tecnologıá” for a grant.

Supporting Information Available: Tables of atomic coordinates and equivalent isotropic displacement coefficients, anisotropic thermal parameters, experimental details of the X-ray studies, and bond distances and angles for 7 and 9. This material is available free of charge via the Internet at http://pubs.acs.org. OM0005295

Formation of Imine− Vinylidene− Osmium (II) Derivatives by Hydrogen

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