Organometallics 1990, 9, 2234-2242
2234
Chemistry of Phosphide-Bridged Mixed-Metal Complexes. Insertion of Atkynes into the Phosphido Bridge of (CO),RU(~-PP~,)CO(CO)~.X-ray Structures of (CO)aRu(p-Ph,PC(O)C(Ph) =C(Ph))Co(CO),, (CO),Ru(p-Ph,PC(O)C(SiMe,) =C( H))Co(CO),, and (CO) ~ R up-Ph2PC ( (Ph) =C(Ph))CO(CO)3 Rachid Regragui and Pierre H. Dixneuf" Laboratolre de Chimle de Coordination Organique, URA CNRS DO4 15, Campus de Beaulieu, Universitg de Rennes, 35042 Rennes Cedex, France
Nicholas J. Taylor and Arthur J. Carty" Guelph-Waterloo Centre for Graduate Work in Chemlstry, Waterloo Campus, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 361 Received November 30, 1989
The synthesis and characterization of two series of heterobinuclear Ru-Co complexes are described:
(OC)3Ru(~-q3-Ph2PCOC(R1)=C(R2))Co(C0)3 (2; R', R2 = Ph, Ph (a), Ph, CECPh (b),H, Ph (c), H, tBu (3a-d). Complexes 2 result from (a),SiMe3,H"(e),H, H (E))and (OC),RU(~-~~-P~~PC(R')=C(R~))CO(CO)~
1, which has a very the regioselective reaction at 30-35 "C of alkynes a-f with (OC)4R~(p-PPh2)Co(C0)3 reactive phosphido bridge. Decarbonylation of complexes 2a-d at 60-65 "C affords complexes 3a-d. The reversibility of the insertion of the alkyne in 2a is shown by its reaction with tBuC=CH, which leads to 2d. Complexes 2a, 2c, and 2e react with Ph2PH to give the carbonyl monosubstitution products (Ph2PH)(CO)2Ru(Ph2PCOC(R1)=C(R2))Co(CO), (4). Molecular structures of 2a, 2e, and 3a have been determined by X-ray diffraction. Crystal data: 2a, triclinic, space group PI,a = 8.280 (1) A, b = 12.419 (2) A, c = 14.966 (2) A, CY = = 99.55 (l)", y = 90.10 (I)",2 = 2; 2e, monoclinic, space group I2/a, a = 17.054 (2) A, b = 99*58 10.846 (2) , c = 30.671 (4) A, 0 = 107.81 (l)",2 = 8; 3a, monoclinic, space group P2,/c, a = 17.041 (2) A, b = 10.721 (1) A, c = 17.511 (2) A, 6 = 101.56 (l)",2 = 4. Each structure shows a bonding Ru-Co interaction (2a, 2.6577 (4) A; 2e, 2.6710 (6) A; 3a, 2.6479 (7) A), Ru-C(R2) and Ru-P linkages, and the resence of a five-membered (2a, 2e) or four-membered metallacycle (3a) with coordination of the C(R!=C(R2) double bond to the cobalt atom.
(l)",l
Introduction The participation of phosphido groups in the chemistry of bi- and polynuclear p P R 2 complexes is now well established,' and insertion of small molecules into M-(pPR2)-M systems has provided routes to some novel bridging ligands, including the general class p-&P=X (X = O,, X = CH2 or CRR',v4), alkenyl- and butadienylphosphines? and diphosphinesa6 We have been exploring in detail the chemistry of the binuclear p-PPh, mixedmetal complex (OC)4Ru(p-PPh2)Co(CO),(1),7-" and in a (1) For a selection of recent references to phosphido bridge reactivity see: (a) Roaenberg, S.; Geoffroy, G. L.; Rheingold, A. L. Organometallics 1985, 4, 1184. (b) Nucciarone, D.; MacLaughlin, S. A.; Taylor, N. J.; Carty, A. J. Organometallics 1988, 7, 106. (2) Klingert, B.; Werner, H. J. Organomet. Chem. 1983, 252, C47. (3) (a) Yu, Y. F.; Chan, C. N.; Wojcicki, A.; Calligaris, M.; Nardin, G.; Balducci, G. J. Am. Chem. SOC.1984,106,3704. (b) Yu, Y. F.; Galluci, J.; Wojcicki, A. J. Chem. Soc., Chem. Commun. 1984,653. (c) W n b e r g , S.; Whittle, R. R.; Geoffroy, G. L. J. Am. Chem. SOC.1984,206,5934. (d) Rosenberg, S.; Geoffroy, G. L.; Rheingold, A. L. Organometallics 1985, 4, 1184. (4) (a) Werner, H.; Zolk, R. Organometallics 1985,4,601. (b) Werner, H.; Zolk, R. Chem. Ber. 1987, 220, 1003. ( 5 ) (a) Henrich, K.; Iggo, J. A.; Mays, M. J.; Raithby, P. R. J. Chem. Soc., Chem. Commun. 1984,209. (b) Henrick, K.; McPartlin, M.; Iggo,
J. A.; Kemball, A. C.; Mays, M. J.; Raithby, P. R. J. Chem. Soc., Dalton Trans. 1981, 2669. (c) Horton, A. D.; Mays, M. J.; Raithby, P. R. J. Chem. Soc., Chem. Commun. 1985, 247. (6) (a) Yu, Y. F.;Chan, C. N.; Wojcicki, A.; Calligaris, M.; Nardin, G.; Balducci, G. J. Am. Chem. SOC.1984,106, 3104. (b) Yu, Y. F.; Wojcicki, A.; Calligaris, M.; Nardin, G. Organometallics 1986, 5 , 47. (7) (a) Regragui, R.; Dixneuf, P. H. J. Organomet. Chem. 1982,239, C12. (b) Regragui, R.; Dixneuf, P. H.; Taylor, N. J.; Carty, A. J. Or-
ganometallics 1984,3, 1020.
(8) Regragui, R.; Dixneuf, P. H.; Taylor, N. J.; Carty, A. J. Organo-
metallics 1986, 5 , 1.
preliminary communication we described the insertion of diphenylacetylene and CO into the phosphido bridge, affording (alkenylcarbony1)phosphineand alkenylphosphine ligands.l0 Although examples of P-C coupling reactions involving phosphido groups and acetylenes have been rare until recently,12-14there has been an increasing number of reports of alkyne insertions into both p-PR, and p-PR bridges.15-18 Such reactions have potential for the generation of new P-C bonds and for the introduction of carbon fragments into clusters. In this paper we describe in detail the reactions of 1 with mono- and disubstituted acetylenes R'C=CR2 to generate the complexes RuCoC(R')=C (R2)) (2) and their decarbo(CO),( p-PPh,C (0) nylation products RuCo(C0),(p-PPh2C(R')=C(R2))(3), (9) (a) Guesmi, S.; Dixneuf, P. H.; Taylor, N. J.; Carty, A. J. J. Organomet. Chem. 1986.303. C47. (b) Guesmi. S.: Dixneuf. P. H.: Suss-Fink. G.; Taylor, N. J.; C&ty,'A. J. Or&nometnllics 1989,s; 307. (c) Guesmi; S.; Taylor, N. J.; Dixneuf, P. H.; Carty, A. J. Organometallics 1986, 5 , 1964.
(10) Regragui, R.; Dixneuf, P. H.; Taylor, N. J.; Carty, A. J. Organometallics 1984, 3, 814. (11) (a) Regragui, R.; Dixneuf, P. H. J. Organomet. Chem. 1988,344, C11. (b) Regragui, R.; Dixneuf, P. H. New J. Chem. 1988, 12, 547. (12) (a) Yasufuku, K.; Yamazaki, H. J. Organomet. Chem. 1972,35, 367. (b) Bamett, B.; Kruger, C. Cryst. Struct. Commun. 1973, 2, 347. (13) Smith, W. F.; Taylor, N. J.; Carty, A. J. J. Chem. Soc., Chem. Commun. 1976,896. (14) Carty, A. J. Adu. Chem. Ser. 1982, No. 296, 163. (15) Zolk, R.; Werner, H. J. Organomet. Chem. 1983, 252, C53. (16) Knoll, K.; Orama, A.; Huttner, G. Angew. Chem., Znt. Ed. Engl. 1984, 23, 976. (17) Lunniss, J.; MacLaughlin, S. A.; Carty, A. J.; Sappa, E. Organometallics 1985, 4, 2066.
(18) For a recent review of reactions of alkynes with phosphinidene clusters see: Knoll, K.; Huttner, G. Angew. Chem., Znt. Ed. Engl. 1987, 26, 743.
0276-7333/90/2309-2234$02.50/0 0 1990 American Chemical Society
Organometallics, Vol. 9,NO.8, 1990 2235
Phosphido-Bridged Mixed-Metal Complexes
the exchange of alkynes in 2, and the X-ray structures of 2a (R' = R2= P h ) , 2e (R' = SiMe,, R2= H), and 3a (R' = R2 = Ph). Experimental Section General P r d u r e s . Standard techniques, with Schlenk type equipment for the manipulation of air-sensitive compounds under a blanket of nitrogen, were employed. All solvents were dried (sodium benzophenone ketyl for T H F and ether, CaH2 for hexane and benzene, and P205for CH2C12)and nitrogen-saturated prior to use. Chromatographic separations were made on thick-layer plates of Merck silica gel. Instrumentation. Infrared spectra were recorded on Perkin-Elmer 225 and 457 instruments using either Nujol mulls or cyclohexane solutions in matched 0.5-mm NaCl cells. 'H and 31P NMR spectra were generally measured on a Bruker WP-80 spectrometer operating at 80 MHz for 'H, 32.38 MHz for 31P,and 20.115 MHz for '% or on a Bruker AC 300 spectrometer operating a t 300.13 MHz for 'H. 31Pspectra were proton noise decoupled, and shifts are reported relative to external 85% H3P04. 'H and shifts are relative to Me4%. Microanalyses were obtained from the CNRS laboratory, Villeurbanne, France. Syntheses. Synthesis of (CO)3Ru(p-Ph2PC(0)C(R1)=C(R*))Co(CO), (2). Complex l7(1mmol, 0.54 g) and 1mmol of an alkyne were dissolved in 60 mL of THF. The orange mixture was stirred a t 30-35 "C and became progressively red. The reaction was monitored by infrared spectra of cyclohexane solutions and by thin-layer chromatography on silica gel plates (eluant hexane). The residual orange complex 1 migrates first, followed by a small amount of the orange derivative 3 and then by the yellow-orange major product 2. After 12 h a t 30-35 OC the solvent was removed under vacuum. The products were dissolved in 2-3 mL of dichloromethane and chromatographed on a column of Florisil. To eliminate residual complexes 1 and 3 from 2, hexane was used as the eluant and then a dichloromethane-hexane mixture eluted complex 2, which was recrystallized from a dichloromethane-ether mixture. Complex 2a was obtained from 0.18 g (1 mmol) of diphenylacetylene in 80% (0.58 g) yield; mp 168-170 "C. Anal. Calcd for C3Hm07PCoRu: C, 55.10; H, 2.80; P, 4.30. Found: C, 55.21; H, 2.74; P , 4.40. MS: m / e 664 ([M - 2CO]+), 636 ([M 3CO]+), 608 ([M - 4CO]+),580 ([M - 5CO]+), 552 ([M - 6CO]+), 523.966 (calcd for [M - 7COI' (C26H2$Co'02R~)523.968). In addition ions corresponding to the formation of 1 ( m / e 542 (M1+ = [RuCo(C0),(PPh2)]+), 513.860 (calcd for [M - CO]+ (C18Hlo06PCo'02Ru)513.859)) were observed. IR (C6H12, VCO, cm-'): 2093 (m), 2039 (s), 2022 (m), 1994 (m), 1878 (w) 1608 (vs). 31P(1H)NMR (32:38 MHz, CDzC12,300 K, 6 (ppm)): +38.6. 'H NMR (80.00 MHz, CD2C12,300 K, 6 (pprn)): 7.45 (m, C&5]. Complex 2b was obtained from 0.20 g (1 mmol) of 1,4-d1phenylbutadiyne in 70% (0.52 g) yield; mp 160-165 "C. IR (C&, vm, cm-'): 2130 (w),2096 (m), 2042 (s), 2022 (m), 2007 (m), 1898 (w), 1611 (w). 31P(1H)NMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): +39.4. 'H NMR (80.00 MHz, CD2C12,300 K, 6 (pprn)): 7.43 (m, C&)* Complex 2c was obtained from 0.10 g (1 mmol) of phenylacetylene in 80% (0.50 g) yield; mp 163-165 "C. IR (C&12, VCO, cm-'): 2094 (m),2045 (s), 2025 (m), 2008 (m), 1900 (w), 1606 (vs). 31P(1HJNMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): 42.9. 'H NMR (80.00 MHz, CD2C12,300 K, 6 (pprn)): 7.44 (m, c6H5);5.43 (d, 3 J p = ~ 38 HZ, P-co-cff=). Complex 2d was obtained from 0.08 g (1 mmol) of 3,3-dimethylbutyne in 70% (0.44 g) yield; mp 172-175 "C. IR (C6H12, uc0, cm-'): 2096 (m), 2045 (s), 2022 (m), 2008 (m), 1897 (w), 1610 (vs). 31P(1HJNMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): +42.9. 'H NMR (80.00 MHz, CDZClz,300 K, 6 (pprn)): 7.45 (m, C&); 5.44 (d, 3 J p ~= 38 Hz, P-cO-CH=); 1.27 (9, %u). Complex 2e was obtained from 0.10 g (1 mmol) of (trimethylsily1)acetylene in 85% (0.54 g) yield. The same yield was obtained when the mixture was heated for 6 h a t 65 OC instead of 12 h at 30-35 "C; mp 190-200 "C dec. Anal. Calcd for C24H2007PSiCoRu:C, 45.08; H, 3.15; P, 4.84; Si, 4.39. Found: C, 45.44; H, 3.17; P, 4.82; Si, 3.87. IR (C6H12, uco, cm-'): 2090 (m), 2035 (s), 2018 (m), 1994 (m), 1893 (m, broad), 1602 (w). 31P(1H)NMR (32.38 MHz, CDCl,, 300 K, 6 (pprn)): +50.50. 'H
NMR (300.13 MHz, CDC13, 300 K, 6 (ppm)): 8.65 (d, Ru-CH=,
'JPH = 1.3 Hz); 7.95-7.20 (m, C6H5);0.26 (s, SiMe3). Complex 2f was obtained by reaction of 1 mmol of 1 in 60 mL of T H F with an excess of acetylene (1atm) for 7 days a t room temperature. Red crystals were obtained in 90% (0.51 g) yield; mp 165-170 "C dec. Anal. Calcd for C21H1207PC~R~: C, 44.46 H, 2.13; P, 5.46. Found C, 44.52; H, 2.15; P , 5.44. IR (CgH12, uc0, cm-'): 2092 (m), 2036 (s), 2018 (m), 2000 (m), 1900 (w), 1625 (w). 31P('HJNMR (32.38 MHz, CDC13, 300 K, 6 (ppm)): +37.40 (9). 31PNMR (6 (ppm)): +37.40 (d, , J ~ H = 39.6 Hz). 'H NMR (300.13 MHz, CDCI3, 300 K, 6 (pprn)): 8.19 (dd, Ru-CH=, 3Jm = 6.6 Hz, 'JpH = 1.1 Hz); 7.95-7.25 (m, C6H5);5.43 (dd, =CH3J" = 6.6 HZ, 3 J p = ~ 38.00 HZ). Synthesis of (OC)&U(~-$-P~~C(R')=C(R~))CO(CO)~ (3). Method A from Complex 1. Complex 1' (1 mmol, 0.54 g) and 1 mmol of an alkyne were dissolved in 60 mL of THF, and the mixture was stirred a t 60-65 "C for 6 h. The solvent was evaporated, and the products were dissolved in 2-3 mL of dichloromethane and chromatographed on a column of Florisil (eluant hexane). A first red fraction contained the residual complex 1, and then complex 3 was eluted. Complexes 3 were recrystallized from hexane. Method B from Complexes 2. Complex 2 (0.5 mmol) was dissolved in 40 mL of THF, and the mixture was heated for 6 h a t 60-65 "C. The reaction products were chromatographed on a column of Florisil (eluant hexane), and the orange isolated complex 3 was recrystallized from hexane. Complex 3a (R' = R2 = Ph). Method A. From 0.54 g of 1 and 0.18 g of diphenylacetylene, 0.40 g (60%) of yellow-orange crystals of 3a was obtained. Method B. From 0.36 g (0.5 mmol) of 2a, 0.19 g (55%) of 3a was obtained; mp 180-182 "C. Anal. Calcd for C32Hm06PCoRu: C, 55.58; H, 2.91; P, 4.48. Found: C, 55.38; H, 2.94; P, 4.19. MS: m/e 692 ([MI+),663.945 (calcd for [M - CO]' (C3,Hm05PCo'%u) 663.942), 636 ([M - 2CO]+),608 ([M - 3CO]+),580 ([M - 4CO]+), 552 ([M - 5CO]+), 524 ([M - 6CO]+), 496 ([M - 7CO]+). Ions corresponding to the decomposition products of complexes 3 were also found R U ~ ( ~ - P P ~ ~ ) m ~ (/ eC742 O ) ([MI+), ~, 713.884 (calcd for [M - CO]+ (CzsHzo05P2Ru2) 713.887). IR (C6H12, VCO, cm-'1: 2080 (m), 2027 (s), 2021 (m), 2007 (w), 1984 (m), 1897 (w). 31P(1HJ NMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): -28.6. 'H NMR (80.00 MHz, CD2C12,300 K, 6 (ppm)): 7.42 (m, C6H5). Complex 3b (R' = P h ; R2 = -C=CPh). Method A. From 0.54 g of 1 and 0.2 g (1mmol) of 1,4-diphenylbutadiyne, 0.46 g (65%) of 3b was obtained. Method B. From 0.37 g (0.5 mmol) of 2b, 0.21 g (60%) of 3b was obtained; mp 170-175 "C. IR (C8Hl2,VCO, cm-'): 2079 (m), 2033 (s), 2021 (m), 2006 (m), 1993 (m), 1908 (vs). 31P(1H)NMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): -21.7. 'H NMR (80.00 MHz, CD2C12,300 K, 6 (ppm)): 7.43 (m, C6H5). Complex 3c (R' = H,R2 = Ph). Method A. From 0.54 g of 1 and 0.10 g of phenylacetylene, 0.40 g (65%) of red-brown crystals of 3c was obtained. Method B. From 0.33 g (0.5 mmol) of 2c, 0.20 g (60%) of 3c was obtained; mp 178-185 "C. IR (CeH12, YCO, cm-'): 2078 (m), 2029 (s), 2018 (m), 1994 (ws), 1980 (m), 1890 (vs). 31P('HJNMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): -30.6 (s). 'H NMR (80.00 MHz, CD2C12,300 K, 6 (ppm)): 7.42 (m, C6H5);5.10 (d, P-CH=, 2JpH= 6.0 Hz). Complex 3d (R' = H,R2 = tBu). Method A. From 0.54 g of 1 and 0.08 g (1mmol) of 3,3-dimethylbutyne, 0.36 g (60%) of dark red crystals was obtained. Method B. From 0.31 g (0.5 mmol) of 2d, 0.15 g (50%)of 3d was obtained; mp 185-190 "C. IR (C6H12, VCO, cm-'): 2080 (m), 2032 (s), 2015 (m), 1992 (w), 1979 (m), 1910 (vs). 31P('HJNMR (32.38 MHz, CD2C12,300 K, 6 (pprn)): -34.45 (s). 'H NMR (80.00 MHz, CD2C12,300 K, 6 (pprn)): 7.43 (m, C6H5);4.90 (d, P-CH=, 'JPH = 6 Hz); 1.23 (s, t B ~ ) . Preparation of Complex 2d from 2a. Complex 2a (1mmol, 0.72 g) was dissolved in 60 mL of THF, and the solution was cooled to -30 "C for the introduction of 1 mmol of 3,3-dimethylbutyne via a syringe. The reaction mixture was stirred at 50 "C for 6 h, until the monitoring of the reaction by infrared spectroscopy indicated that the ratio 2d/2a remained constant. The products were chromatographed on a column of Florisil (eluant dichloromethane). From the first eluted fraction, dark red crystals of 2d
co-,
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Organometallics, Vol. 9, No. 8, 1990
Regragui et al.
Table I. Crystal Data, Intensity Collection, Reduction, and Refinement 2a 2e 3a formula CSRH~~O~PCORU Cz4Hm0,PSiCoRu C~~H~O~PCORU*O.~CH~C~~ formula 639.55 734.02 719.56 mol wt monoclinic monoclinic triclinic cryst syst Pi I2/a p21lC space group 17.054 (2) 17.041 (2) 8.280 (1) a, A 10.846 (2) 10.721 (1) 12.419 (2) b, A 30.671 (4) 17.511 (2) 14.966 (2) c, A 90 90 99.58 (1) a , deg 107.81 (1) 101.56 (1) 99.55 (1) P, deg 90 90 90.10 (1) 1,deg 8 4 2 z 5401 (1) 3134.3 (5) 1495.8 (4) v, A3 1.573 1.555 1.597 d(calcd), g/cm3 13.28 12.00 11.73 ~(MK Oa ) , cm-' graphite-monochromated Mo K a (A = 0.71609 A) radiation Syntex P21 diffractometer 0.23 X 0.24 X 0.27 0.27 X 0.29 X 0.30 0.24 X 0.25 X 0.28 cryst size, mm 8/28 8/20 8/20 scan type 546 545 550 28 range, deg 2.93-29.30 3.45-29.30 2.55-29.3 scan speed, deg/min 0.8' below K a , to 0.8" above K a 2 scan width 723; 0016 008; 800 137; 410 std rflns -2 -2 -2 change in stds, % 3779 4132 5281 no. of data measd 3051 3465 4191 no. of data obsd ( I Z S u ( 0 ) 0.61-0.76 0.68-0.81 0.67-0.80 transmissn factors 397 464 469 no. of variables 0.025 0.033 0.029 0.039 1.86 - 0.03421F01+ 0.00Ot$llFoIz 2.1 - 0.0281FJ + 0.000381F,12 2.96 - 0.0268)F01+ 0.000441F,12 weighting scheme 0.28 0.82 (solvent C1) electron dens level in final diff map, e/A3 0.51 0.24 g (60%) of complex 4e was obtained; mp 160-165 OC dec. were isolated in 60% (0.40 g) yield. From the second fraction IR (CBH12,uc0, cm-'): 2041 (w), 2022 (vs), 1983 (s), 1974 (s), 1863 0.18 g (25%) of complex 2a was recovered. (m, broad), 1616 (w). 31P(1H)NMR (32.38 MHz, CDCl,, 300 K, Preparation of (Ph2PH)(CO)2Ru(p-~3-Ph2PCO(R1)=Cd (ppm)): trans isomer (95%) 50.05 (d, PCO), 26.14 (d, Ph2PH), (R2)}Co(CO),(4). A solution was prepared with 0.5 mmol of VPp= 249.0 Hz; cis isomer (5%) 48.41 (d, PCO), 26.79 (d, Ph2PH), complex 2 and 40 mL of THF and was stirred while 1m o l (0.18 *JPp= 24.9 Hz. ,'P NMR (6 (pprn)): trans isomer 50.05 (d), 26.14 g) of diphenylphosphine was added with a syringe. The reaction (dd, 'JpH= 368.3 Hz). The 'JpHvalue for the cis isomer was not was monitored by infrared spectra in cyclohexane solution or by observed due to the weak intensity of the signals. 'H NMR (300.13 thin-layer chromatography (eluant 111 dichloromethanehexane). MHz, CDCl,, 300 K, 6 (ppm)): 8.3-7.0 (m, C,H5); trans isomer The solvent was removed under vacuum. Approximately 3-4 mL 5.88 (dd, Ph2PH, 'JpH = 364.0 Hz, 3JpH = 3.1 Hz), 0.07 (s,SiMe,); of Florisil and 10 mL of dichloromethane were added to the oily = 386.0 Hz, ,JpH = 12.5 Hz), cis isomer 5.23 (dd, Ph2PH, ' J ~ H red reaction products; the heterogeneous mixture was stirred while 0.09 (s, SiMe,). The alkyne proton was masked by the phenyl dichloromethane was evaporated. The residual solid powder was proton signals. placed at the top of a column of Florisil. Elution with a mixture X-ray S t r u c t u r e Analyses. Collection a n d Reduction of of hexane and dichloromethane gave first a fraction containing X-ray Data. Crystals of 2a were grown from CH2ClZ-hexaneas the residual complex 2, then a fraction containing a small amount orange-yellow prisms. Recrystallization of 2e from n-hexane of an unidentified product, and finally the complex 4. Complexes afforded orange prisms, and crystals of 3a were obtained from 4 were recrystallized from a dichloromethane-hexane mixture. n-hexane as orange-yellow hexagonal prisms. A suitable crystal 4a (R' = R2 = Ph). From 0.36 g (0.5 mmol) of 2a, after 10 was attached to a goniometer head via a glass fiber on a brass h of reaction a t room temperature, the orange complex 4a was pin and mounted on a Syntex P2', Data General Nova controlled isolated in 70% yield (0.30 g); mp 150-155 "C. IR (CsH12,UCO, automatic diffractometer for preliminary examination. Polaroid cm-'): 2040 (w), 2019 (vs), 1985 (m), 1969 (s), 1856 (m, broad), rotation photographs in combinations with the Syntex autoin1620 (w). 31P11H]NMR (32.38 MHz, CDCl,, 300 K, 6 (pprn)): dexing and cell refinement procedures were used to identify +42.80 (d, PCO); 23.88 (d, PhZPH); 'Jpp = 256.3 Hz. 31PNMR possible unit cells. Space group and crystal data for cells refined (6 (ppm)): 42.80 (d), 23.88 (dd, 'JpH = 366.0 Hz). 'H NMR (300.13 with 15 reflections well dispersed in reciprocal space are given MHz, CDCl,, 300 K, 6 (pprn)): 8.1-6.9 (m, C,H,); cis isomer (2%) in Table I. For complex 2a, the choice of the centric space group 5.69 (dd, PH, 'JpH = 379.2 Hz, 3JpH= 3.2 Hz); trans isomer (98%) Pi was initially based on centric E statistics and a Patterson map 5.24 (dd, PH, *JPH = 375.5 Hz, ,JPH= 3.9 Hz). consistent with single occupancy of the asymmetric unit. The 4c (R' = H, R2 = Ph). From 0.32 g (0.5 mmol) of 2c, after choice of space group 12/a rather than acentric l a was based on either 12 h of reaction a t 25 "C or 6 h of reaction a t 50 "C, the similar reasoning. The correctness of both of these assignments orange complex 4c was isolated in 60% yield (0.24 g); mp 160-165 was confirmed by the solution and refinement of the structures. "C. IR (C6H12,uco, cm-I): 2040 (w), 2021 (vs), 1984 (s), 1974 (s), 1870 (m, broad), 1618 (m). 31P{1HJ NMR (32.38 MHz, CDCl,, 300 Intensity data were collected on the P2' diffractometer for appropriate crystals as indicated in Table I. Intensities were K, d (pprn)): trans isomer (62%) 42.27 (d, PCO), 29.31 (d, Ph,PH, measured via 8/28 scans with a variable scan rate set to optimize VPp= 253.9 Hz); cis isomer (38%) 44.97 (d, PCO), 13.57 (d, measurements on weak and strong reflections. Background NMR (6 (pprn)): trans isomer 42.27 PhzPH, 2Jpp = 21.9 Hz). measurements were made a t the beginning and end of each scan (d), 29.31 (dd, lJpH = 372.9 Hz); cis isomer 44.97 (d), 13.57 (dd, for a time equal to half of the total scan. For each crystal, 'JPH= 373.1 Hz). 'H NMR (300.13 MHz, CDCl,, 300 K, d (pprn)): instrumental and compound stability were monitored by mea8.1-7.0 (m, C,H& trans isomer 5.70 (d, =CH, 3JpH= 36.3 Hz), surement of two standard reflections after every 100 reflections. 5.10 (dd, PH, 'JPH = 372.9 Hz, ,JpH = 4.5 Hz); cis isomer 5.50 None of the three compounds exhibited any significant decay over (dd, PH, 'JPH= 373.1 Hz, 3 J p = ~ 7.2 Hz), 5.48 (dd, =CH, ,JPH the period of data collection. Measured reflections were flagged = 37.8 Hz, 4 J p ~= 0.8 Hz). as unobserved when I 5 3u(I), where u was determined from 4e (R' = SiMe,, R2 = H). From 0.32 g (0.5 mmol) of 2e, after counting statistics. Data were corrected for Lorentz and polar6 h of reaction at 50 " C (no reaction occurred at 25 "C for 6 h),
Phosphido-Bridged Mixed-Metal Complexes Table 11. Atomic Positional Parameters (Fractional, XIO') for 2a atom X Y 2 2221.0 (2) 730.6 (3) 2256.2 (2) Ru 2321.8 (3) 3415.6 (5) 1082.6 (3) 3226.2 (6) 1643.6 (5) 2624.0 (10) 456 (2) 2237 (3) -1799 (3) 2986 (2) 784 (3) -1528 (3) 4394 (2) 3202 (2) -421 (4) 1019 (2) 752 (2) 5723 (4) 1058 (2) 812 (3) -163 (2) 3215 (2) -804 (2) 4246 (4) 2212 (2) 3370 (2) 5901 (3) 1105 (2) -898 (4) 2216 (3) 1335 (3) 2746 (2) -680 (4) 2838 (2) -30 (4) 3595 (3) 1491 (3) 896 (3) 4791 (4) 1571 (2) 1596 (4) 512 (3) 2912 (2) 3912 (5) -44 (3) 2400 (2) 3067 (2) 4608 (4) 2235 (2) 3304 (2) 2789 (4) 3207 (2) 2600 (2) 4376 (4) 4253 (2) 2515 (4) 2136 (3) 1172 (3) 4483 (2) 1989 (4) 1106 (4) 5381 (3) 1830 (5) 2011 (4) 6055 (3) 2163 (5) 5833 (3) 2983 (4) 2630 (5) 4940 (2) 2810 (4) 3046 (3) 2724 (3) 3975 (2) 5807 (4) 1903 (3) 4466 (2) 6313 (4) 5205 (3) 2082 (4) 7577 (5) 5470 (3) 3089 (4) 8364 (5) 3905 (3) 4983 (3) 7891 (5) 3724 (3) 4246 (3) 6627 (5) 1772 (2) 4695 (2) 2336 (4) 2405 (3) 5442 (3) 3345 (5) 2502 (3) 6543 (3) 3026 (6) 1982 (3) 6904 (3) 1707 (6) 1356 (4) 6178 (4) 686 (7) 1247 (3) 990 (6) 5077 (3) 475 (2) 3031 (4) 2880 (2) -135 (2) 2002 (3) 2284 (4) -1010 (2) 1748 (3) 2699 (5) 2372 (4) -1256 (3) 3865 (6) -651 (3) 3250 (4) 4617 (6) 213 (3) 4207 (5) 3514 (3) ization effects, but with small values of p(Mo KG)no corrections for absorption were deemed necessary. Observed intensities were reduced to structure factors in the normal way. Solution and Refinement of X-ray Data All three structures were solved by heavy-atom methods, the cobalt and ruthenium atoms being identified in Patterson maps and light atoms via subsequent Fourier syntheses. Least-squares refinement of positions and isotropic thermal parameters for non-hydrogen atoms afforded R values (R = CIFoI - ~ F c ~ / ~of~0.62 F ofor ~ 2a, ) 0.077 for 2e, and 0.076 for 3a. Conversion to anisotropic temperature factors and further cycles of refinement followed by a difference Fourier calculation in each case allowed the identification of all hydrogen atoms in the three molecules. In subsequent refinement to convergence hydrogens were included and isotropic temperature factors refined. For complex 3a, the asymmetric unit contains a half molecule of the solvent of crystallization (CH2C12) disordered about an inversion center. Carbon atom C(33) was refined with 50% occupancy. Appropriate weighting schemes (Table I) were used in the final cycles. Final difference maps were featureless, with residual electron density levels listed in Table I. Final R and R, (R, = [x.w(lFoI- IFc1)2/~.wlFo12]1/2) values for 2a, 2e, and 3a were respectively 0.028 and 0.031,0.025 and 0.029, and 0.033 and 0.039 All calculations used the full matrix and were carried out on IBM 4341 systems in the University of Waterloo Computer Centre. Scattering factors for heavy atoms were taken from ref 19 and for hydrogen atoms from the data of Stewart et a1.20 Programs used in the calculations are those described (19) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, England, 1974; Vol. IV.
Organometallics, Vol. 9, No. 8,1990 2237 Table 111. Ru-CO Ru-C( 1) Ru-C(3) Ru-C(8) CO-c(5) Co-C(8) P-C(7) P-C(28) C(2)-0(2) C(4)-0(4) C(6)-0(6) C(7)-C(9) C(8)-C(l0)
Selected Bond Lengths (A) 2.6577 (4) Ru-P 1.958 (3) Ru-C(2) 1.923 (4) Ru-C(5) 2.152 (3) Co-C(4) 1.789 (4) Co-C(6) 2.008 (3) Co-C(9) 1.865 (3) P-C(22) 1.818 (3) C(1)-O(1) 1.121 (5) C(3)-0(3) 1.125 (5) C(5)-0(5) 1.129 (4) C(7)-0(7) 1.463 (4) C(8)-C(9) 1.500 (4) C(9)-C(16)
for 2a 2.3335 (8) 1.972 (4) 2.380 (4) 1.809 (4) 1.788 (4) 2.180 (3) 1.822 (3) 1.128 (4) 1.126 (5) 1.157 (5) 1.225 (4) 1.426 (4) 1.496 (4)
Table IV. Selected Bond Angles (des) for 2a CO-Ru-P 74.68 (2) Co-Ru-C(l) 124.3 (1) Co-Ru-C(2) 99.3 (1) c o - ~ ~ - c i ~ j138.6 i i j 41.1 (1) Co-Ru-C(8) 47.9 (1) CO-Ru-C (5) 174.0 (1) 92.0 (1) P-Ru-C(2) P-Ru-C( 1) 94.1 (1) P-Ru-C (5) P-Ru-C(3) 90.8 (1) 92.1 (1) C(1)-Ru-C (2) 81.6 (1) P-Ru-C(8) 94.1 (1) C(l)-Ru-C( 5) 88.3 (1) C(l)-Ru-C(3) 171.1 (1) C(2)-Ru-C (3) 93.3 (1) C(l)-Ru-C(8) 93.8 (1) C(2)-Ru-C(8) C(2)-Ru-C(5) 81.6 (1) 92.2 (1) 174.5 (1) C( 3)-Ru-C (8) C(3)-Ru-C(5) 125.9 (1) 85.9 (1) Ru-Co-C(4) C(5)-Ru-C(8) 129.2 (1) Ru-Co-C(5) 61.1 (1) Ru-CO-C (6) 52.5 (1) Ru-Co-C(9) 79.9 (1) Ru-Co-C (8) 101.4 (1) 97.8 (1) C(4)-Co-C(6) C(4)-Co-C(5) 102.1 (1) C(4)-Co-C (8) 140.0 (1) C(4)-Co-C(9) 108.9 (1) 98.9 (1) C(5)-Co-C(8) C(5)-Co-C (6) 140.7 (1) C(6)-Co-C (8) 103.1 (1) C(5)-CO-C(9) 109.7 (1) C(8)-Co-C(9) 39.6 (1) C(6)-Co-C (9) 114.9 (1) 103.8 (1) Ru-P-C (2 2) Ru-P-C(7) 105.1 (1) 123.1 (1) C(7)-P-C(22) Ru-P-C (28) 102.9 (1) 105.5 (1) C(22)-P-C(28) C(7)-P-C(28) 175.4 (1) 176.6 (1) Ru-C( 2)-O( 2) Ru-C(l)-O( 1) 175.1 (1) 177.6 (1) co-c(4)-0(4) Ru-C (3)-0( 3) 127.5 (1) 77.8 (1) Ru-C(5)-0(5) Ru-C (5)-Co 174.2 (1) 154.6 (1) C0-C(6)-0(6) co-c(5)-0(5) 112.0 (1) 120.5 (1) P-C(7)-C(9) P-C(7)-0(7) 79.3 (1) 127.4 (1) Ru-C (8)-Co C(9)-C(7)-0(7) 120.1 (1) 120.5 (1) Ru-C(8)-C( 10) Ru-C(8)-C(9) 129.1 (1) 76.7 (1) Co-C(8)-C( 10) Co-C(8)-C(9) 90.2 (1) C(9)-C(8)-C(lO) 117.4 (1) CO-C(9)-C(7) 126.6 (1) 63.7 (1) CO-C (9)-C (16) Co-C(9)-C(8) 120.6 (1) C(7)-C(9)-C(16) 115.8 (1) C(7)-C(9)-C(8) C(8)-C (9)-C (16) 122.7 (1) elsewhere.21 For the three molecules 2a, 2e, and 3a, respectively, atomic positional parameters are listed in Tables 11,V, and VI11 along with compilations of pertinent bond lengths (Tables 111, VI, and IX) and angles (Tables IV, VII, and X). Anisotropic thermal parameters (Tables S1, S4, and S7), hydrogen atomic positions and isotropic thermal parameters (Tables S2, S5, and S8), and additional bond lengths and angles (Tables S3, S6, and S9) are available as supplementary data,n as are structure factors for the three molecules (Tables S10, S11, and S12).
Results and Discussion Synthesis and Spectroscopic Properties of Complexes 2a-f. The phosphido-bridged 'carbonyl complex 1 reacts readily with mono- and disubstituted alkynes at 35 "C in THF as shown in Scheme I. The principal products formed under these mild conditions are the yellow-orange complexes 2a-f. For the alkynes R 1 C S R 2 (R' = R2 = P h ; R1= Ph, R2 = C E C P h ; R' = Ph, R2 = H; R1= tBu, R2 = H)smaller amounts of the second products 3a-d were also obtained. At 65 O C , the complexes 3a-d were the major products. Subsequent experiments con(20) Stewart, R. F.; Davidson, E. R.; Simpson, W. T. J. Chem. Phys. 1965, 42, 3175. (21) Carty, A. J.; Mott, G. N.; Taylor, N. J.; Yule, J. E. J. Am. Chern. SOC.1978, 100, 35. (22) See paragraph on supplementary material at the end of the paper.
Regragui et al.
2238 Organometallics, Vol. 9, No. 8, 1990 Table V. Atomic Positional Parameters (Fractional, XlO') for 2e atom
31
N
2
3509.2 (2) 2910.1 (3) 2104.4 (5) 1691.1 (7) 4258 (2) 5134 (2) 3564 (2) 3914 (2) 3826 (3) 1613 (2) 859 (1) 3980 (2) 4563 (2) 3545 (2) 3555 (2) 3466 (3) 2104 (3) 1592 (2) 2992 (2) 2161 (2) 1137 (4) 964 (4) 2526 (3) 1604 (2) 1321 (2) 944 (3) 845 (3) 1123 (3) 1503 (3) 1696 (2) 2197 (2) 1857 (3) 1023 (3) 524 (2) 854 (2)
1852.6 (3) -414.3 (5) 2029.4 (8) -136.0 (10) 2596 (3) 1087 (3) 4436 (3) -475 (3) -2320 (4) -1685 (3) 893 (2) 2341 (4) 1393 (4) 3477 (4) -224 (4) -1563 (5) -1195 (4) 1057 (3) 982 (3) 622 (3) -1564 (5) 993 (6) -502 (6) 3516 (3) 4213 (4) 5336 (4) 5770 (4) 5092 (4) 3968 (4) 1521 (3) 1332 (4) 998 (5) 845 (4) 1021 (4) 1364 (4)
1257.0 (1) 1278.6 (2) 833.0 (3) 2020.7 (4) 496 (1) 1968 (1) 1641 (1) 679 (1) 1900 (2) 570 (1) 1047.0 (8) 770 (1) 1693 (1) 1501 (1) 929 (1) 1672 (2) 845 (2) 1178 (1) 1717 (1) 1608 (1) 1771 (2) 2149 (2) 2553 (2) 829 (1) 436 (1) 446 (1) 843 (2) 1237 (2) 1230 (1) 242 (1) -31 (1) -486 (1) -665 (1) -397 (1) 53 (1)
Table VII. Selected Bond Angles (deg) for 2e CO-Ru-P Co-Ru-C(2) Co-Ru-C(B) P-Ru-C (2) P-Ru-C(8) C(l)-Ru-C(3) C(2)-Ru-C(3) C(3)-Ru-C(8) Ru-CO-C(~) Ru-Co-C(8) C(4)-Co-C(5) C(~)-CO-C(~) c(5)
