Aryldiazo complexes. Structure of a hydridoaryldiazo complex of

Miescher, ref 26. (46) K. R. Grundy, C. A. Reed, and W. R. Roper, Chem. Commun., 1501. (1970). (47) See Frenz and Ibers, ref 45. (48) J. H. Enemark an...
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Aryldiazo Complexes

Inorganic Chemistry, Vol. 14, No. 11, 1975 2617

A. Cotton and G.Wilkinson, “Advanced Inorganic Chemistry”, 3rd ed, Interscience, New York, N.Y., 1972, p 713; R. D. Harcourt and J. A. Bowden, J . Inorg. Nucl. Chem., 36, 1 1 15 (1974). The typical N-0 distance in linear nitrosyl complexes is 1.17 8, (B. A. Frenz and J . A. Ibers, MTP Int. Rev. Sci.. Phys. Chem., Ser. One, 11, 33 ( I 972) which is considerably closer to that distance in free NO (1.15 8,)than to the corresponding distance in free NO+ (1.06 A). However, we prefer to view the linear nitrosyl ligand as though it were NO+ in an excited singlet state, e.g., IT+ ( N - 0 = 1.19 A); see Herzberg and Miescher, ref 26. K. R. Grundy, C. A. Reed, and W. R. Roper, Chem. Commun., 1501

(59) G. LaMonica, M. Freni, and S.Cenini, J . Organomet. Chem., 71, 57 (1974). (60) D. Giusto and G. Cova, Gazz. Chim.Ital., 102, 265 (1972). (61) C. G.Pierpont and R. Eisenberg, Inorg. Chem., 12, 199 (1973). (62) B. L. Haymore and J. A. Ibers, Inorg. Chem., in press. (63) J. H. Enemark and R. D. Feltham, Proc. Nail. Acad. Sci. U.S.A.,69, 3534 (1972). (64) W. R. Scheidt and J. L. Hoard, J . Am. Chem. SOC.,95, 8281 (1973). (65) T. E. Nappier, D. W. Meek, R. M. Kirchner, and J . A. Ibers, J . Am. Chem. Soc., 95, 4194 (1973). (66) L. Busetto, A. Palazzi, R. Rosi, and M. Graziani, Gazz. Chim. Ita/,, 100, 894 (1970). (67) D. M. P. Mingos and J . A. Ibers, Inorg. Chem., 10, 1035 (1971). (68) D. A. Snyder and D. L. Weaver, Inorg. Chem., 9, 2760 (1970). (69) C. S. Pratt, B. A. Coyle, and J. A. Ibers,J. Chem. SOC.A , 2146 (1971). (70) A. Araneo, V. Valenti, and F. Cariati, J . Inorg. Nucl. Chem., 32, I877 (1970); S. D. Robinson and M. F. Uttley, J . Chem. SOC., Dalton Trans.. 1 (1972). (71) W. Silverthorn and R. D. Feltham, Inorg. Chem., 6, 1662 (1967). (72) R. Davis, B. F. G. Johnson, and K. H. AI-Obaidi, J . Chem. SOC.,Dalton Trans., 508 (1972). (73) R. W. Adams, J. Chatt, N. E. Hooper. and G. J. Leigh, J . Chem. Soc., Dalton Trans.. 1075 (1974). (74) C. A. Reed and W. R. Roper, Chem. Commun., 1459 (1969); R. J. Fitzgerald and H. W. Lin, Inorg. Chem., 11, 2270 (1972). This structure is undoubtedly similar to the square-planar geometry found in [Ir(~-CF~C~CF~)(NO)(PP~~)]Z: J. Clemens, M. Green, M. Kuo, C. J. Fritchie, J. T. Mague, and F. G. A. Stone, J . Chem.Sm., Chem. Commun.. 53 (1972). (75) M. 1. Bruce, J . Organomet. Chem., 53, 141 (1973). (76) N. G . Connelly, Inorg. Chim. Acta, Rev.. 6, 47 (1972).

(1970).

See Frenz and Ibers, ref 45. J . H. Enemark and J. A. Ibers, Inorg. Chem., 6, 1575 (1967). G. Dolcetti, L. Busetto, and A. Palazzi, Inorg. Chem., 13, 222 (1974); W. E. Carroll, F. A. Deeney, and F. J. Lalor, J . Chem. Soc., Dalton Trans., 1430 (1974).

C. P. Brock, J. P. Collman, G. Dolcetti, P. H . Farnham, J. A. Ibers, J. E. Lester, and C. A. Reed, Inorg. Chem., 12, 1304 (1973). K. R. Laing and W. R. Roper, J . Chem. SOC.A , 2149 (1970); Chem. Commun., 1556 (1968).

To the extent of our knowledge, these compounds have not yet been prepared. W. E. Carroll. F. A. Deeney, and F. J. Lalor, J . Chem. Soc.. Dalton Trans., 1430 (1974). C. G.Pierpont and R. Eisenberg, Inorg. Chem., 11, 1094 (1972). D. M. P. Mingos and J. A. Ibers, Inorg. Chem., 10, 1479 (1971). G. R. Clark, J. M. Waters, and K. R. Whittle, Inorg. Chem., 13, 1628 (1974). See ref 32 for the structure of an analogous hydroxo complex. G. A. Reed and W. R. Roper, J . Chem. SOC.,Dalron Trans., 1014 (1973).

Contribution from the Department of Chemistry and Materials Research Center, Northwestern University, Evanston, Illinois 6020 I

Aryldiazo Complexes. Structure of a Hydrido-Aryldiazo Complex of Osmium, O s H ( C O ) ( N 2 C 6 H 5 ) ( P ( C 6 H s ) 3 ) 2 * C H 2 C 1 2 M A R T I N COWIE, BARRY L. HAYMORE, and J A M E S A. IBERS*

AlC50374V Received June 3, 1975 The structure of OsH(C0) (N~C~HS)(P(C~H~)~)~.CH~C~~ has been determined crystallographically and consists of discrete molecules of the aryldiazo complex and solvent. This complex of Os(0) is five-coordinate and has a distorted trigonal-bipyramidal coordination geometry about the osmium atom. Owing to the reduced steric requirements of the hydrido ligand, the P(1)-Os-P(2) and N ( 1)-Os-C(l) angles change from the respective idealized values of 180 and 120’ to 164.37 (6) and 138.0 (3)’ indicating a distortion toward a quasitetrahedral geometry. The singly bent, phenyldiazo ligand occupies an equatorial coordination site and possesses an unusually long osmium-nitrogen bond length with Os-N = 1.867 (6) A, N-N = 1.211 (8) A, N-C = 1.460 (10) &Os-N-N = 171.1 and N-N-C = 118.5 (7)’. Thecompound crystallizes from dichloromethane as solvated crystals in space group C,’-Pl of the triclinic system with a = 13.440 (2) A, b = 13.48 1 (1) A, c = 12.528 (2) A, 01 = 114.30 (l)’, 0 = 101.82 (l)’, y = 81.43 (1)O, and 2 = 2. Based upon 5340 unique reflections with Fo2 > 3a(F02) the structural data were refined by full-matrix, least-squares methods to R = 0.046 and RW = 0.057.

(c)’,

Introduction Much current interest has been stimulated in aryldiazo ligands, not only because of their close relationship to nitrosyl and dinitrogen ligands but also because of their varied modes of bonding and their utility as intermediates in the syntheses of aryldiazene and arylhydrazine ligands.1-9 Structural studies have shown that the aryldiazo ligand can adopt a doubly bent geometrylo,11 or a singly bent geometry12 or that it can bridge two metal atoms.13 In this regard, it is similar to the isoelectronic nitrosyl ligand; indeed, nitrosyl and aryldiazo ligands have been compared structurally in almost identical coordination environments in [RhCl(L)(PhP(CH2CHKH2PPh2)2)] [PFs] (bent Rh-N-N) and in RuCh(L)(PPh3)2l6,17 (linear Ru-N-N) where L = NNAr, NO. The geometry and chemical reactivity seem to be very sensitive to the electronic characteristics of the central metal and especially to the coordination geometry about it. For this reason, structural studies are especially useful in understanding the types of reactions which aryldiazo ligands undergo. Recently, acyl-, aroyl-, and alkyldiazo ligands have been prepared starting with dinitrogen complexes of rhenium, molybdenu ‘1, and tungsten.18 Many aryldiazo ligands, es10,14115

pecially those attached to Ru, Os, Rh, Ir, and Pt, react with coordinating and noncoordinating protonic acids to form complexes of cis-aryldiazene.2-4,19 A rhenium complex containing a singly bent aryldiazo ligand has been observed to react with H+at the nitrogen atom which is attached to the aryl group, thus forming an unsymmetrical form of phenyldiazene, Re=N=NHPh.zO In an aryldiazo complex the value of v(NN), when not vibrationally coupled with other ligand modes, is indicative of the mode of coordination of the aryldiazo group.lOJ6 Despite the relatively low value of v(NN) at 1543 cm-l for OsH(CO)(NNPh)(PPh3)2, we felt that it was indicative of a singly bent mode of coordination for the diazo ligand.21 For this reason and because this reactive complex is the first hydrido-aryldiazo complex to be synthesized we have determined its solid-state structure crystallographically and report it here. This is the third five-coordinate, aryldiazo complex to be studied crystallographically and the second one found to possess a trigonal-bipyramidalcoordination geometry about the metal.22 Experimental Section Crystal Preparation. The title complex was prepared according

2618 Inorganic Chemistry, Vol. 14, No. 11, 1975 Table I. Summary of Crystal Data and Intensity Collection

Cowie, Haymore, and Ibers

found to decrease nearly linearly by about 10% during the course of data collection, presumably as a result of crystal decomposition or desolvation. The observed intensities were modified to correct for this apparent crystal decomposition. The slightly low values of the Formula wt density for several crystals in the range 1.49-1.51 g/cm3 indicated Formula that these crystals may have lost some of the solvent of crystallization. a The calculated densities with no solvent and with one solvent molecule b 13.481 ( 1 ) A per osmium atom are 1.395 and 1.535 g/cm3, respectively. C 12.528 (2) A The intensities of 6731 reflections were measured ( h Z 0) out to a 114.30 (1)" 28 = 126' using nickel-filtered copper X-radiation: past this point 101.82 (1)" P 81.43 (1)" very few reflections were above background. The data were processed 7 V 2020 A3 in the usual way using a value of 0.04 for p.25 Only those 5340 unique 2 2 reflections with F a 2 > 3a(F0*) were used in subsequent calculations. Density 1.5 35 g/cm3 (calcd) An absorption correction was applied to the data using gaussian 1.50 (1) g/cm3 (exptl) integration.26 The R index for averaging 152 pairs of symmetry-related C: -Pi (triclinic) Space group reflections was 1.3% after the absorption correction was applied. Crystal dimensions 0.28 X 0.20 X 0.09 mm-, Structure Refinement. The structure was solved using a sharpened, Triclidc prism with {Oll), Crystal shape origin-removed Patterson synthesis to locate the osmium atom and (101 1,and {211} faces well the two trans phosphorus atoms. Subsequent refinements and difdeveloped ference Fourier syntheses using the centrosymmetric space group PI Crystal vol 0.0043 mm3 were used to locate the remaining nonhydrogen atoms as well as the Temp 22O 35 phenyl hydrogen atoms. The structure was refined using full-matrix, Radiation Cu Kor, ( h 1.54056 A) prefilleast-squares techniques. The isotropic model (seven rigid-body phenyl tered with 1 mil of Ni foil groups and no hydrogen atoms) almost converged to R indices of R Transmission factors 0.259-0.577 = CllFol - IFcI~/CIFO~ = 0.064 and Rw = [Zw(lFal- IFcI)2/ P 82.38 cm-l CwFa2]l/2 = 0.091. During the refinements the quantity minimized Receiving aperture 4.0 mm wide by 3.9 mm high; 30 cm from crystal ~, lF01 and IFc[ are the observed and was Cw(lF01 - I F C ~ )where Takeoff angle 2.8" calculated structure amplitudes and where the weights, w , are taken Scan speed 2.0" in 2e/min as ~ F O ~ / U ~ ( F Atomic O * ) . scattering factors were taken from Cromer 0.9" below K a , to 0.9" above Scan range and Waber's tabulation.27 The anomalous dispersion terms for Os, CI, and P were included in Fc.28 All phosphine phenyl groups and Ka, Background counts 10 sec also the diazo phenyl group during the first calculations were refined 20 limits 3.0-1 26.0' as rigid, planar bodies with a constant and uniform C-C distance of Final no. of variables 217 1.392 8, and with individual isotropic thermal parameters for each Unique data used, Fo2 > 3u(FO2)5310 carbon atom. Although all phenyl hydrogen atoms were located in 1.75 electrons Error in observation of unit wt the difference Fourier syntheses, their positions were idealized, and they were included as fixed contributions in final anisotropic reto the published method by deprotonating OsH(CO)(HNNPh)finements; the C-H distance was assumed to be 0.98 A,the C C H (PPh3)3+ with NaOH in acetone-methanol at -2OO.23 The resulting angle was assumed to be 120', and the isotropic thermal parameter brown, microcrystalline powder was recrystallized from dichloroof a hydrogen atom was assumed to be 1.O A* larger than the thermal methane in the dark at -10' to yield beautiful brown crystals of the parameter of the carbon atom to which it was attached. The hydrogen 1:l methylene chloride solvate. Because the crystals slowly lost solvent atoms of the solvents, H(1) and H(2), were also placed in idealized of crystallization, freshly prepared crystals were mounted in capillaries positions in a plane normal to the Cl(l)-C(2)-Cl(2) plane (C-H = in an atmosphere of the solvent in order to prevent desolvation during 1 .OO A, H-C-H = 109') and were included as fixed contributions. data collection. Except for this desolvation, the compound was stable in air under ambient conditions. Anal. Calcd for C U H ~ S C I ~ N ~ O O S P ~ :Additional refinements in which the nongroup atoms were treated anisotropically and the hydrogen atom contributions were included C, 56.59; H, 4.10; N, 3.00; CI, 7.59. Found: C, 56.80; H , 4.16; N, converged to give agreement indices of R = 0.049 and RW= 0.062. 2.76; CI, 6.86. Elemental analyses were performed by Micro-Tech Because five of the six carbon atoms in the diazo phenyl ring had large Laboratories, Inc., Skokie, Ill. As judged by a color change, brown thermal parameters (in the range 9-13 &), the six carbon atoms were to black, the powder was slightly photosensitive; however, the larger refined as individual atoms with anisotropic thermal parameters in single crystals seemed to be much less sensitive. the last cycles of refinement. The final agreement indices are R = Crystallographic Data. Preliminary film data showed the crystals 0.046 and Rw = 0.057 after convergence. to belong to the triclinic system with extinctions (hkl, h_+ k + 1 odd) A final difference Fourier synthesis of residual electron density characteristic of the space groups Cil-I1 and GI-11, which are revealed nothing interesting except one peak (2.1 e/8,3) located exactly nonstandard settings of P1 and PI. A cell reduction failed to reveal in the trigonal plane near the expected position of the hydrido ligand. a cell of higher symmetry. The centrosymmetric space group was The remaining residuals were near the phosphine phenyl groups shown to be the correct one on the basis of the following results: ( I ) (0.9-0.6 e/A3) or the solvent (0.9-0.6 e/8,3). A typical carbon atom the successful refinement of the structure with acceptable positional had a height of 4.2 e/8,3. Another difference synthesis using only parameters, thermal parameters, and agreement indices; (2) the clear data with (sin 0 ) / h 5 0.35 8,-1 caused the large peak in the trigonal and distinct location of all 35 phenyl hydrogen atoms in difference plane to decrease in height (1 .O e/A3) but its position did not change Fourier syntheses; (3) the statistical equivalence of the intensities of significantly. This electron density seems to come primarily from 152 pairs of reflections related by a center of inversion. For the sake the hydrido ligand, but its position, 1.2 8, from Os (expected Os-H of convenience, intensity data were collected using the body-centered = 1.7 8,),29 and its height are apparently altered by the presence of cell and then transformed to the primitive cell prior to the handling osmium residuals. A comparison of the observed and calculated and processing of the data.24 Using a least-squares procedure based structure amplitudes showed no need for an extinction correction. In on the angular positions of 17 hand-centered reflections in diverse order to check for the possibility of desolvation of the data crystal, regions of reciprocal space (47.6 5 20 I58.0), accurate unit cell the occupancy factor for the entire solvent molecule was refined during dimensions were determined using a narrow X-ray source. See Table most of the least-squares refinements. Because the value of this factor I for pertinent crystal information and details of data collection. The remained near unity (0.934 (6)), the value of the occupancy factor mosiacity of the crystal was found to be acceptable for the 8-28 scan was set at 1.O and not refined during the last several cycles of antechnique based on w scans performed with an open counter. isotropic refinement. All but two unobserved reflections obey the Data collection was carried out using a Picker four-circle difrelation IF$ - Fa21 < 4u(F02). There were no trends of the quantity fractometer equipped with a scintillation counter and a pulse height Cw(lFol- lFc1)2 as a function of IF& diffractometer setting angles, analyzer which was adjusted to accept 90% of the Cu Ka peak. or Miller indices. Background counts were measured at both ends of the scan range The final positional and thermal parameters of atoms and groups with both the counter and crystal stationary. The intensities of six appear in Tables 11-IV, and root-mean-square amplitudes of vibration standard reflections were measured every 100 reflections. These were Compd

Inorganic Chemistry, Vol. 14, No. 11, 1975 2619

Aryldiazo Complexes

Table 11. Positional and Thermal Parameters for the Nongroup Atoms of OsH(CO)(N,Ph)(F'Ph,),

..............:........*.*.*:. ...................................................

A $!%.*..*..i

os

0.1536201261

PI11

0.218491151

P 12 I

CLIII

Bl18

0 a 0 3 648 ( 1 5 I

0.286O0131 0.37122(161 0.15512 (171

0.3204141 0.4716(41

0.5143131 0 . 3 4 4 8 (51

0.0908161

CLIZI CIPI

0.41121121

HI11

0.2332151

0~4330llll 0 . 3 2 4 0 151

0.1623112l 0.3zai16)

a 151 19.2151 z0.11i51 6 . 2 (41

Nizi

0.~9za151 0.0575161

0 . 3 8 9 6 1 51

0.1695161

0.3438(61 0 , 3 5 0 6 (71

1.9161

7.7151 7.0161

Cl11

0.0656151

5.72121 5.901111

822

0.2072861261 0~110721151 0 , 2 6 6 5 2 I151

5.8411~1

22.

a.1151

5.7413) 6.741141 5.691131

833

7.9a131 7.221161 a.071171

!!f..

....

***%*+...*

-0.35121

0.61121

....

3L..

2.72(21

-0.ZOllOl

1.OllIlll

2.81112l

-0.i81ioi

i.oiiiii

z.53(;21

15.1131 33.0171

52~11111

-2.7131 -0.3151

6.4161

31.9181

i0.91i41 6.6151

10.41161

-a.61iz)

3.a(iz1 0.5141

1.11131 3.3141 2.8151 2.8151

9.7161

-0.4141

16.1171

-0 09 141

1.6151

4.8151 14.7161

7.9171

-0.6151

1.4151 0.215)

12.3161

14.6171

-2.115)

4.0(51

5ell61

7.5161

10.6181

-1.2151

2.1161

2.7161 -4.81101

0.0000151 0.29 7 1 171

0.1514l51

Oe3966t61

10.9161

0.4092 (71

0.4517101

CIZ C13

0.23381101

0~516911#1

0.52921101

8.4171 17~91131

0.61461131

0~63211111

zz.iii8i

15.91121 z3.41i~1

18~01131

0.24761121

ia.91i41

-7,51101 -9.51141

9.Sllll 13.01141

C14 C15 Cl6

0~31991131

0.67781101

0~6532Illl

20,21161

10.61101

13.51131

-3.71101

5.01121

0~30Z4111I

0.6504191

0~57691111

20.31141

11.71101

14.51141

-9.01101

1.91111

1.51101

0~3720110l

0.55511101

0.473619)

17m51121

14~71111

12.91111

-8.11101

4,5191

1.5191

0111

Cll

-7.01i31 -0.619)

.................................................................................................................................. 'ESTItllTEO

S T A N D l R O D E V I A T I O N S I N TME L E A S T S I G N I F I C A N T

FORM OF THE P N I S O T R O P I C

THERMAL E L L I P S O I O 1 s t E X P I - I B l l H

L R E THE T H E R H A L C O E F F I C I E N T S X

10

I N T H I S A N 0 I L L SUBSEQUENT T A B L E S . 'THE 2 2 t B 2 2 K t 5 3 3 L ~ + 2 8 1 2 H K * 2 8 1 3 M L t 2 8 2 3 K L 1 1 . THE O U P N T I T I E S G I Y E N I N T H E T l B L E

F I G U R E I S 1 PRE G I Y E N I N P A P E N T H E S E S

2

m

Figure 1. Stereoview of a unit cell of OsH(CO)(NNPh)(PPh,),.CH,C1,. The x axis is horizontal to the right, t h e y axis is almost vertical, and the z axis is perpendicular t o the paper coming toward the reader. The vibrational elipsoids are drawn at the 20% probability level. The phenyl hydrogen atoms have been omitted.

RING 4

Figure 3. Trigonal coordination plane with some bond angles and distances for OsH(CO)(NNPh)(PPh,),-CH,CI,. The approximate location of the hydrido ligand is shown. The vibrational elipsoids are drawn at the 50%probability level.

Figure 2. Perspective view of OsH(CO)(NNPh)(PPh,),.CH,CL, showing the lettering and numbering scheme. The solvent molecule and phenyl hydrogen atoms have been omitted. The vibrational elipsoids are drawn at the 50%probability level. are given in Table V. A listing of the observed and calculated structure amplitudes for those data used in the refinements is available.30

DiscussiQn Description of the Structure. The structure of OsH(CO)(NNPh)(PPh3)2.CHzClzconsists of molecules of the osmium complex and of the solvent with two molecules of the complex and two solvent molecules in the unit cell as shown in the stereodrawing of the unit cell, Figure 1. A perspective view of the complex together with the numbering scheme is shown in Figure 2. The complex has a trigonal-bipyramidal coordination geometry, but it is somewhat distorted owing to the reduced steric requirements of the hydrido ligand. Similar distortions have been observed in RhHCl(SiC13)(PPh3)2,31

RuHCl(PPh3)3,32 CoH(PF3)4,33 and RhH(PPh3)4.34 The phosphine ligands occupy the two axial sites and are approximately trans to each other. However, they both bend directly toward the hydrido ligand by somewhat differing amounts, 4.0 (4)' for P( 1) and 1 1.6 (5)' for P(2), causing the P(l)-Os-P(2) angle to decrease to 164.37 (6)' (see Table VI). This can be compared with the same angle in [Fe(C0)2(NNPh)(PPh3)2][BF4]22 at 175.85 ( 8 ) O and in Os(C0)3(PPh3)235 at 180' (symmetry imposed). The phenyldiazo, carbonyl, and hydrido ligands all lie in the trigonal plane. Figure 3 shows the trigonal coordination plane together with some pertinent bond distances and angles. The phenyldiazo and carbonyl ligands both move toward the hydrido ligand and away from each other, thus causing the C(l)-Os-N(I) angle to open up to 138.0 (3)'; compare this to the same angle in the cationic dicarbonyl complex of iron at 121.4 (3)'. The carbonyl ligand is essentially linear, but it is bent by a small, significant amount, 4.3 ( 7 ) O . The oxygen atom of the carbonyl ligand remains almost exactly in the

2620 Inorganic Chemistry, Vol. 14, No. 11, 1975

Cowie, Haymore, and Ibers

Table 111 D E R I V E D PARAMETERS F O R THE R I G I O GROUP ATONS O F OSH(CO1 (NZPHI ( P P H 3 ) Z

.....,*.Ell.*.....l.*,**~.*.**

~ ! ? , . * . * . ~ . , . ~ * . . ! . . I

.....* 9TON

0,260714)

-0.0008(41

0.3898151

4.29114)

c22

0.2811(51

-0.6089(4)

0.4995 ( 4 )

6.311211

C23

0.2589151

-0.1522(6)

0.5091151

7.45(251

224

-0.1874141 -0.1793141

0.409016l

7.76(261

C25

0.216315) 0.195915)

3.2993(51

C25

0.2181(51

-0.086015)

0.2897(4)

C31

0.3943(31

C32 C33

0.4542(4) 0.5358(41

0.067914) -0.OZblI4)

c34

c35

0.5575(4) 0.4977141

C36

0.41blI10

0.1258141

c41

0,3482 (41

0.2059(41

C4Z

0,4531 ( 4 )

0.2114I4l

c43

0.4326(31

0.2789(51

c44

0.427:15)

c45 C46

..

..,.

:.*..*

*.*.+.

E. A

CZl

.*.

!*....~....~..*f~~~......~:~~..~

0.4151 13) 0.4741 (51 0.5874 I51

O.208315I 0.140214l

5.641221

0.1889151

7.48(25)

-0.0155151 -0.0183(51

0.6418(31

0.3056151

5.981191

0.5829(4)

0.3737(4)

6.77 1211

C55 C61

-0.0033151 0.0 143 1 4 )

0.46961Cl 0 . 2 2 4 2 (41

0.3250141 0.014914l

5.94 (131

5.441181

C62

0.0308t3l

0.1579 ( 4 1

-0.0927151

5.04(16)

O.PZZZ(5I

5.961191

C63

0.1233(41

-0.1965141

5.19 I 1 9 1

0.1509~51

61121201

C64

0.072314l 0 e1673 1 4 1

0.1823(5)

6.24121)

C65

0.2208 (3)

0.1551 ( 5 1 0.2215l41

-0.1926 141 -0.0850(51

6~16120l 6.66 ( 2 1 I

0.225115)

5.611181

C66

0.0187(41

5. R 9 ( 1 9 l

4.33(141

C71

0 - 1 7 9 31 4 1 -0.G91113I

0.2560(41

0.5186(41

0.2187(4)

0. 1061 ( 5 1

4.13(141

5.553415) 0 6682 1 5 )

5.21(171

C72 C73

-0.1059(3) -0.2016(4l

Om1168141

0.1011(51

4.96(16)

6.59(211

0.0756(31

0.0569 (51

5.681161

C.340915l

0.7487(41

6.98(221

C74

-0.2824(31

0.136215l

0.0178151

5.97(191

0,3222 ( 4 1

0.3353(51

1.7140 ( 5 1

7.45(241

C75

-0.2676(41

0 . 2 3 8 1 (41

0.022815l

6.lrP(21l

0.2328131

0.2673(51

0.5990151

6.411211

C76

-0.1719t4l

@.27¶4( SI

0 .Ob69151

5.56(1EI

C51 C52 C53

0.0164(51

6.94(231

C54 C55

0.286414)

6.03IPOl 3.97113)

0.2849(5)

-0.0622(41 -0.0043(51

0.089715)

0.0139(4)

O.CGl615l

4.141141

4.15l14l

~ . , . . ~ . ~ . . ~ . ~ . ~ . * ~ . ~ . * ~ . ~ . ~ . . * . . . . ~ * . , ~ ~ ~ . . * ~ . ~ . ~ . ~ . ~ * . ~ * . * . . * . ~ C * . ' ~ . t

R I G I D GROUP P A R A N E T E R S

a

GROUP

C

*It . . l ~ * . . * . * . 1 . ' . . * ~ * . * ' . ~ . * * . ' * ~ . * . * . ~ . * ~ * ~ * . * . * . ~ * . * ~ . ~ . * ~ . ~ *

2

Y

X

C

DELTA

1.923(41

2.808 1 1 0 1

2.869(3)

0.6337(31

1.289(4)

0.2570(3)

-3.38219)

-2.767 1 3 1 -2.0 37 ( 3 1

-0.72113l 1 . 2 5 1 (4)

0.0 318 ( 3 1

'0.3994141

0.223613l

RING4

0.2734131

QING5

-0.03082(281

0.5285(31

RING6

0,12579 ( 2 8 1 -0.186761281

0.18968(291

-0.088913)

0.1775(3)

ETb

1s 672(1O)

0.23849(23)

0.47593(281 0.3877(3)

SIYG7

EPSILON

C .216(3l

RING2 RING3

-0.094113l

B

C

-1.07814L 0.370 131

0.0619131

1.216181

-1.48214l

-2.733 1 3 ) 3.037 ( 3 1

-2.92213)

~ . . . ~ . * . ~ . . . . . * * ~ . . . ~ . . . ~ * * * . * * ' . . . . ~ . ~ ~ . ' . ~ . * . I ' . " * . . . * . , . . . . . . . . . * . * . . ~ ~ . . . . . * . . ~ . . * ~ . . . . . . . * . * . . ~ * . . . . . . . . . . . i l l l C I . . * * . . * * . . . . . 1

1\

Xc,

Yc,

SILON.

LND

Z

A9E T H E F S A C T I O N A L C O O R O I N A T E S OF THE O R I G I N O F THE R I G I O GQOUP.

A V O E T A ~ R 4 D I A N S I HAVE J E E N D E F I N E D P R E V I O U S L Y 1 S . J .

LA PL4CA AN0 J.A.

Table IV. Idealized Positional Coordinates for Hvdroeen Atoms Atom

x

Y

z

Atom

x

Y

z

H(12) H(13) H(14) H(15) H(16) H(22) H(23) H(24) H(25) H(26) H(32) H(33) H(34) H(35) H(36) H(42) H(43) H(44) H(45)

0.177 0.194 0.324 0.439 0.422 0.311 0.272 0.200 0.166 0.204 0.439 0.577 0.614 0.513 0.376 0.498 0.564 0.454 0.278

0.472 0.634 0.746 0.697 0.535 0.048 -0.108 -0.251 -0.238 -0.081 -0.066 -0.127 -0.029 0.130 0.190 0.169 0.284 0.390 0.379

0.517 0.688 0.723 0.588 0.418 0.567 0.583 0.415 0.230 0.214 0.326 0.221 0.118 0,121 0.226 0.499 0.692 0.827 0.769

H(46) H(52) H(53) H(54) H(55) H(56) H(62) H(63) H(64) H(65) H(66) H(72) H(73) H(74) H(75) H(76) H(l)a H(2)a

0.211 0.026 0.002 -0.024 -0.027 -0.003 -0.034 0.036 0.196 0.285 0.216 -0.051 -0.213 -0.349 -0.324 -0.162 0.460 0.373

0.264 0.437 0.628 0.720 0.621 0.431 0.136 0.077 0.131 0.243 0.302 0.075 0.006 0.108 0.280 0.349 0.483 0.398

0.576 0.059 0.141 0.338 0.454 0.372 -0.096 -0.270 -0.264 -0.083 0.092 0.127 0.053 -0.012 -0.004 0.071 0.228 0.195

a

These hydrogen atoms are attached to the solvent molecule.

trigonal plane and bends toward the aryldiazo ligand which is a good T-acceptor ligand. Although hydrogen atoms are not easy to find, especially when they are near very heavy metal atoms, the presence of the hydrido ligand was verified through several means. (1) The largest peak of residual electron density was found in the trigonal plane very near the location expected for the hydrido ligand (see Experimental Section). (2) The coordination geometry about the osmium atom indicates the presence of a stereochemically active ligand located approximately in the trigonal plane. (3) The proton NMR spectra of dissolved single crystals of this osmium complex show a distinct 1:2:1 triplet a t T 19.5 with JPH = 21 Hz in CD2C12. (4) Infrared spectra of crushed single crystals show the Os-H stretching vibration at 2010 cm-I; v(C0) = 191 1 cm-1.

8

T H E S I G I O GROUP O B I E N T A T I O N bHGLES D E L T A .

IEERS,

LCTA C R Y S T A L L 0 G Q . r

189

EP-

511(19651.

Table V. Root-Mean-Square Amplitudes of Vibration (A) for OsH(COj(NNPh)(PPh,), .CH, C1, Atom

os P(1) P(2) N(1) N(2) C(1) O(1)

C(2) Cl(1) Cl(2) C(11) C(12) C(13) C(14) C(15) C(16)

Min

Intermed

Max

0.2073 (5) 0.215 (2) 0.207 (2) 0.221 (8) 0.238 (9) 0.221 (10) 0.244 (8) 0.283 (13) 0.336 (4) 0.396 (5) 0.235 (10) 0.247 (12) 0.240 (11) 0.239 (14) 0.223 (12) 0.259 (13)

0.2182 (5) 0.222 (2) 0.226 (2) 0.230 (8) 0.265 (8) 0.232 (10) 0.305 (8) 0.348 (15) 0.443 (5) 0.460 (5) 0.257 (10) 0.306 (14) 0.346 (18) 0.349 (16) 0.329 (15) 0.278 (12)

0.2361 (4) 0.232 (2) 0.232 (2) 0.258 (8) 0.267 (9) 0.273 (10) 0.345 (9) 0.472 (17) 0.624 (7) 0.504 (6) 0.282 (11) 0.529 (16) 0.607 (20) 0.433 (16) 0.457 (16) 0.452 (14)

The distances and angles in the osmium complex are in the range to be expected for osmium-carbonyl-phosphine complexes. Although the average Os-P distance of 2.337 (5) 8, falls in the expected range of 2.33-2.43 A, it is the shortest distance observed in osmium complexes which have two trans triphenylphosphine ligands. The average Os-P distance in [Os(CO)2(NO)(PPh3)2][C104]36 is 2.406 (4) A. The Os-C distance at 1.878 (9) A and the C-0 distance at 1.158 (9) A are typical. Both phosphine ligands adopt the common propeller conformation, and none of the Os-P-C-C torsion angles is unusual. There are no significant intramolecular interactions (