Structure of [Co(CNC6H5)sI ClOkHCC13 reduction, negatives) containing all of the supplementary material for papers in this issue may be obtained from the Journals Department, American Chemical Society, 1155 16th St., N.W., Washington, D.C. 20036. Remit check or money order for $3.00 for photocopy or $2.00 for microfiche, referring to code number AIC405976.
References and Notes (1) A. Davison, N. Edelstein, R. W. Holm, and A. A. Maki, J. Amer. Chem. SOC.,85, 2029 (1963). (2) R. Eisenberg, Progr. Inorg. Chem., 12, 295 (1970). (3) J. A. McCleverty, Progr. Inorg. Chem., 10, 219 (1968). (4) A. L. Balch and R. H. Holm, J . Amer. Chem. SOC.,88, 5201 (1966). (5) G. S,Hall and R. H. Soderberg, Inorg. Chem., 7, 2300 (1968). (6) F. Rohrscheid, A. L. Balch, and R. H. Holm, Inorg. Chem., 5, 1542 (1966). (7) A. L. Balch, F. Rohrscheid, and R. H. Holm, J. Amer. Chem. Soc., 87, 2301 (1965). (8) A. L. Balch and J. E. Parks, J. Amer. Chem. SOC.,96,4114 (1974). (9) M. G. Miles, M. B. Hursthouse, and A. G. Robinson, J. Inorg. Nucl. Chem., 33, 2015 (1971). (10) F. R. Hartley, “The Chemistry of Platinum and Palladium,” Wiley, New York, N.Y., 1973, pp 462-463. (1 1) S.D. Ittel, Ph.D. Thesis, Northwestern University, Evanston, Ill., 1974. (12) J. W. Lauher and J. E. Lester, Inorg. Chem., 12, 244 (1973). (13) D. Cahen, J. R. Hahn, and J. R. Anderson, Rev. Sci. Instrum., 44, 1567 (1973). (14) P. W. R. Corfield, R. J. Doedens, and J. A. Ibers, Inorg. Chem., 6, 197 (1967); R. J. Doedens and J. A. Ibers, ibid., 6, 204 (1967).
Inorganic Chemistry, Vol. 14, No. 3, 1975 645 (15) In addition to various local programs for the CDC 6400 computer, modified versions of the following programs were employed: Zalkin’s FORDAP Fourier summation program, Busing and Levy’s ORFFE error function program, and Johnson’s ORTEP thermal ellipsoid plotting program. Our full-matrix least-squares program NUCIS, in its nongroup form, closely resembles the Busing-Levy O R F E program. Our absorption program is AGNOST. (16) D. T. Cromer and J. T. Waber, “International Tables for X-ray Crystallography,”Vol. IV, Kynoch Press, Birmingham, England, 1974, Table 2.2A; D. T. Cromer and D. Liberman, J . Chem. Phys., 53, 1891 (,-1970) -I
See paragraph at end of paper regarding supplementary material. L. Pauling, “The Nature of the Chemical Bond,” Cornell University Press, Ithaca, N.Y., 1960, p 362. J. M. Robertson and I. Woodward, J . Chem. SOC.,36 (1940). W. C. Hamilton and J. A. Ibers, “Hydrogen Bonding in Solids,” W. A. Benjamin, New York, N.Y., 1968, pp 259-265. K. A. Jensen, 2. Anorg. Allg. Chem., 231, 365 (1937). R. D. Gilliard and G. Wilkinson, J . Chem. SOC.,2835 (1964). R. A. Walton, Can. J . Chem., 46, 2347 (1968). J. R. Halden and N. C. Baenziger, Acta Crystallogr., 9, 194 (1956). F. R. Hartley, “The Chemistry of Platinum and Palladium,” Wiley, New York, N.Y., 1973, pp 490-519. B. R. Penfold and W. N. Lipscomb, Acta Crystdogr., 14, 589 (1961). K. Plumlee and J. A. Ibers, unpublished work. H. Behrens and A. Muller, 2. Anorg. Allg. Chem., 341, 124 (1965). W. Geiger, Southern Illinois University, and M. Suchanski, Northwestern University, personal communication. D. Cahen, Ph.D. Thesis, Northwestern University, Evanston, Ill., 1973.
Contribution from the Department of Chemistry, University of California, Berkeley, California 94720
Structure of the Chloroform Adduct of Pentakis( phenyl isocyanide)cobalt(I) Perchlorate, [CotCNCsHs) 51ClOpHCC131 LEO D. BROWN,2 DOUGLAS R. GREIG, and K E N N E T H N. RAYMOND* Received August 25, 1974
kIC406051
The structure of [Co(CNCsHs)s]ClOcHCCb has been determined from three-dimensional X-ray diffraction data collected by counter methods. The coordination geometry around the d* Co(1) ion is approximately square pyramidal. The complex is situated on a mirror plane. The apical Co-C bond distance is 1.88 (3) A; the two independent basal Co-C bond distances average 1.83 (2) A. The trans Cbasal-Co-cbasal bond angle is 156.5 (lo)’. There is no coordination in the position trans to the apical ligand. For a series of five-coordinate complexes of d8 ions there is a strong corrclation between the relative bond lengths of these complexes and the distance of the central metal ion from the basal plane; as the bond lengths become equal, the metal ion moves out of the basal plane. Comparison of the geometries of the cobalt(1) and cobalt(I1) pentakis(pheny1 isocyanide) complexes gives a direct measurement of the structural effects of a oneelectron oxidation-reduction. The yellow. needlelike crystals of [Co(CNC6H5)5]ClQcHCC13 conform to space group R i / m (C2h2) with a = 10.849 (8) A, b = 17.741 (14) A, c = 11.396 (9) A, and @ = 121.00 (3)’; Z = 2; pcalcd = 1.40 and pobsd = 1.39 g/cm3. The structure has been refined with full-matrix least squares using 647 reflections with Fz > 2a(P) to a final weighted R factor of 8.7%.
Introduction Isocyanide complexes of cobalt and other transition metals have received much interest in recent years. The general area has been reviewed by Malatesta and Bonati3 and more recently by Treichel.4 Of immediate interest are the cobalt(1) and cobalt(I1) isocyanide complexes because of their structural relationship to the analogous pentacoordinate cyanide complex [Co(CN)s]3-. A l t h o u g h the dimer of the [Co(CN)s]3- ion has been known for years and has recently been structurally characterized,s the monomer has eluded isolation until very recently.6 Relatively little structural data are available for a comparison of the isocyanide and cyanide complexes of cobalt. Cotton, Dunne, and Wood have reported the structures of the trigonal-bipyramidal [Co(CNCH3)s]+ ion7 and the corresponding dimer* [Co2(CNCH3)io]4+. More recently, the structure of the cobalt(I1) complex [Co(CNCsHs)s]2+ has been determined;g a discussion of the different forms of the cobalt(I1) phenyl isocyanide system is presented in the structure report9 and elsewhere.l@13 Structure analysis of the [Co(CNCsHs)s]2+ and [Co(C‘NC6Hs)s] + ions presents an op-
portunity to follow the structure and bonding changes in these pentacoordinate transition metal complexes as a one-electron oxidation-reduction takes place. For this reason and for the additional comparisons to be made with other pentacoordinate d* complexes, the structure of [Co(CNCsHs)s]ClO&HCC13 was undertaken. Experimental Section Preparation of [ C O ( C N C ~ A ~ ) ~ ] C ~ ~ ~ All .HC preparative CI~. operations involved were carried out under dry nitrogen atmosphere using Schlenk apparatus. All solvents were reagent grade and deaerated with N2 before use. A mixture of [C0(CNCsH5)5](C104)2~,~~ (0.139 g, 1.80 X 10” mol) and Na2S03 (0.024 g, 1.9 X 10-4 mol) in an ethanol slurry (20 ml) was stirred for several hours at room temperature. As the reduction of the Co(I1) salt proceeded, the blue suspension slowly changed to a clear yellow solution. The reaction mixture was filtered to remove excess Na2S03; the yellow filtrate was reduced in volume by vacuum evaporation and then cooled to -1 5 ” . Thc bright yellow crystalline powder of [Co(CNCsHs)s]C104 was collected and dried under Nz atmosphere. A small amount of the dry [Co(CNCsH5)5]C104 product was
Brown, Greig, and Raymond
646 Inorganic Chemistry, Vol. 14, No. 3, 1975
orientation were determined by a least-squares refinement using the settiiig angles for eight carefully centered reflections. The crystal gave w scan widths at half-heighl of 0.08' for several low-angle reflections. The density of several crystals was determined by the flotation mzt1iotP in toluene-carbon tetrachloride solutions. The measured density was 1.39 g/cir13; the calculated density is I .40 g/cm3 for two formnla units per cell. Crystal data are summarized in Table I. 'The structure was solved by a combination of heavy-atom tech es and direct methods of phasing.l-0 Full-matrix Ieast-squares refinements were carried out for the 647 reflections with F2 > 2 ~ . ( @ ) . 2 1 - 2 4 The positions of the Co and the C1 from the perchlorate were found from the threedimensional Patterson map. Further phasing was accomplished using ~ soiotioii with thc greatest absolute figure the program M U L T A N . ~The of merit determined the positions of I4 atoms. Subsequent difference Follrier and least-,squares calculations located the remainder of the nonhydrogen atoms. The phenyl rings werc refined as rigid groups with a C-C bond length of 1.395 11. All nongroup atoms were refined anisotropically, while group atoms ivere assigned isotropic thermal parameters. Due to the low resolution of the data set, the C-N bond lengths for the three crystallographicdbj Ladependent phenyl isocyanide ligands were constrained, as discussed elsewhere,2~J6to be 1 16 A. After all of the nonhydrogen atoms had refined, the phenyl hydrogens were positioned assuming an ideal D6h geometry for the phenyl rings. The (3-W bond distance was Fixed a i 1.O A with a thermal parameter fixed a t 1 A2 plus the thcrm.al paramcter of the carbon atom to which that hydrogen atom v m bonded. In addition, the H atom for the one6 assuming sp3 bonding at 1.0 i& from the C atom with a thermal parameter of 8.0 &2, With the fixed contribution of all the 1% atoms, the structure refined to Ai := 10.3% and pi2 = 8.'7%.71 The final error in an observation of unit weight is 1.94. The relatively large residuals are dire to the large thermal motion in the structurc. The final difference Fourier showed no peak greater than 0.38 e/A3 (approximately 10% of a carbon atom). 'Table I1 gives the positional and thermal parameters for the nongroup atoms. Group parameters and isotropic thermal parameters for the individual group
Table I. Summary of Crystal Data Molecular formula Mol wt Space group Cell constants' a b
[CO(CNC, W,),]C10 ,.I.ICCl, 793.39 P2,h 10.849 (8) A 17.741 (14) A 11.396 (9) A 121.00 (3)" 1880.2 A 3 2 1.40 g/cm' 1.39 g/cm3 0.012 X 0.016 7.96 cm"
C
P Cell vol Formula units/cell Calcd density Obsd density Crystal dimensions Linear absorption coeff, p a
X
0.027 cni
Ambient temperature of 23"; M o Ma, radiation, h 0.70926 A.
dissolved in chloroform and placed in a Schlenk vessel connected with a glass U tube to another Schlenk vessel containing diethyl ether. As the ether vapor slowly diffused and condensed in the chloroform solution, yellow crystals of [Co(CNCsHs)j]e104.HCel3 suitable for use in X-ray diffraction studies were deposited.15 The crystals are stable in air in the absence of solvent but slowly lose their solvent of crystallization over long periods of time. Anal. Calcd for [Co(CNCsWs)s]C1~3~HCCl3 (mol wt 793.39): C, 54.50; H, 3.30; K, 8.83; C1, 17.87. Found: C, 54.72; H, 3.43; N, 8.83; GI, 18.06. 63d aid Diffi.aSabIl a h . A series of precession photographs showed that the crystal was monoclinic and cxhibiied the absences OkO, k # 2n. These absences are consistent with space groups P21 (C22, No. 4) and P21/m (C2h2,No. 11).16 As shown by the subsequent solution of the structure, P21/m is the correct space group. Intensity data were collected on an automated Picker FACS-1 four-circle diffractometer as previously described.17-19 The data crystal was a yellow needle approximating a regular parallelepiped with dimensions 0.012 X 0.016 X 0.027 cm. The crystal was mounted in a thin-walled glass capillary with the needle axis nearly parallel to the 4 axis of the diffractometer. The unit cell constants and crystal
I
Table 11. Positional Parameters and Anisotropic Thermal Parameters (X l o 3 ) for the Nongroup Atoms Y
X
Z
Pila
0.9121 (5) 0.4530 (15) 0.448 (3) 0.563 (5) 0.348 (4) 0.9838 (11) 0.0337 (16) 0.057 (4) 0.773 (3) 0.6764d 0.8595 (26) 0.8244d 0.0247 (22) 0.0987d
11.8 (9) 17.5 (25) 67 (8) 46 (10) 58 (10) 63 (3) 24.1 (28) 15 (8) 24 (9) 6 (5) 9 (4) 27 (5) 12 (4) 30 (5)
I322 ~
Co
0.1255 (5Ib 0.0006 (16) 0.927 (3) 0.133 (5) 0.036 (4) 0.7401 (13) 0.5509 (14) 0.717 (4) 0.932 (3) 0.8149 (27) 0.2067 (25) 0.2579 (26) 0.1198 (26) 0.1295 (26)
C1, 0, 0, 0,
C1, CI, Cclc C, N,
C, N,
C, N,
'/4
0.1853 (14) '/4 '/4
0.1722 (7) '14
'/4
1/4
0.1774 (14) 0.1323 (13) 0.1772 (13) 0.1296 (11)
_
l
_
_
l
jn
Pi2
P33 l
_
l
l
[Co(CNC, H,)5]C10,.HCC13 023
013
_________I
_
3.30 (26) 8.7 (9) 7.5 (14) 26 (5) 9.0 (19) 20.1 (11) 14.8 (12) 12 (4) 3.2 (17) 5.9 (16) 4.3 (16) 5.3 (1.5)
12.2 (9) 16.0 (26) 104 (12) 37 (11) 35 (8) 31.0 (25) 44 (4) 7 (7) 12 (8) I1 (5) I 1 (5) 23 (4)
2.5 2.2 (11) (I4)
17 (5) (4)
0 0 -9.2 (27) 0 0 14.1 (15) 0 0 0
0 -0.6 0.5 0.8 0.1
(21)
(20) (20) (19)
3.7 (8) 9.7 (22) 67 (9) 31 1 7 ( 98 )) 19.5 (24) 16.0 (27) -5 (6) 6 (7) 1 (4) 2 (4) 17 (4) -2 (4) 11 (4)
0 0 -9.7 0 0 1.2 0 0 0 0 --0.4 --4.0 0.7 2.3
(29) (12)
(21) (20) (20) (16)
'The form of the anisotropic thermal ellipsoid is exp[-(pl,kz 4-p z 2 k 2+ p3312 + 2p,,hk + 2PI3hl + 2p2,k.*)]. Standard deviations of the The carbon of the chloroform molecule. Determined by least signillcant figures are given here and in subsequent tables in parentheses. constraining the cyanide distance to 1.16 A. Table 111. Group Parameters Group Orientation'
-
Group
___I______.
_ l _ _ _ _ _ l
Yc
XC
zc
6
E
r) .
0 -2.056 (1.8) -2.947 (16)
2.884 (22) 2.42 (4) 1.265 ( 1 1)
_ I _ _
Ph 1 Ph, Ph 3
0.5271 (19) 0.3718 (11) 0.1191 (8)
'/4
0.0245 (8) 0.0137 (7)
0.4727 (19) 0.7347 (11) 0.2509 (9)
0 1.02 (4) 3.304 (10)
Thermal Parameters? A'
_
_
~
_
-.-_I
Phenyl group, M C,, Cn z cn3 Cn4 ______.-crl5 crl, ____ I__ 9.7 (13) 9.0 (12) 5.9 (10) 10.5 (14) 10.3 (13) 1 4.6 (9) 18.8 (15) 19.1 (16) 11.9 (30) 15.3 (13) 12.1 (10) 2 7.2 (8) 9.6 (9) 7.9 (8) 8.8 (8) 10.3 (9) 8.2 (8) 3 4.6 (6) a xC,y c , and z c are the fractional coordinates of the group center; the angles 6 , E , and q (in radians) have been defined previously: R. Eisenberg and J. A. Ibers,Inorg. Ckern., 4,773 (1965); S. 9. La Placa and J. A. Ibers, J. Amev. Chem. So;oc., $9, 2581 (1965);Acia CrSstallogr., Isotropic thermal parameters for the individual group atoms. 18, 511 (1965).
Inorganic Chemistry, Vol. 14, No. 3, 1975 647
Structure of [ C O ( C N C ~ H ~ ) S ] C ~ O ~ . H C C ~ ~
u
b-4
Figure 1. Stereoview of the packing and unit cell contents of [CO(CNC,H ,),][ClO,]~HCCl,. The vertical axis is b , and c is in the plane of projection. Table V. Bond Distances (A) and Angles (deg) in [ Co(CNC, H, ) IC10, .HCC13a
,
co-c, co-c, co-c, CO-N, Co-N, CO-N Ccl-Cl, Ccl-Cl, C,-Co-C, Cl-CoC3 C,-C0-C3' CZCO-C~ G-Co-C,'
Figure 2. Perspective view of the [Co(CNC,H,),]+ ion. The crystallographic mirror plane lies in the plane of projection.
Table IV. Root-Mean-Square Amplitude of Vibration along Principal Axes (A X lo3) Axis 3 Axis 1 Axis 2 Atom 282 (9) 217 (9) 229 (9) co 259 (25) 283 (20) 373 (20) 730 (40) 298 (33) 389 (33) 647 (57) 415 (57) 483 (59) 346 (52) 380 (41) 505 (45) 383 (16) 392 (14) 688 (15) 318 (20) 479 (22) 486 (20) 442 (65) 117 (112) 393 (73) 352 (63) 227 (60) 241 (83) 307 (41) 152 (65) 287 (49) 184 (45) 263 (49) 275 (55) 369 (32) 187 (51) 338 (33) 147 (68) 207 (53) 350 (47) 162 (51) 301 (33) 374 (28) atoms are listed in Table 111. Table IV lists the root-mean-square (rms) amplitudes of vibration of the nongroup atoms derived from the anisotropic thermal motion.28
Description of the Structure The crystal structure consists of discrete [Co(CNCsH5)s]+ cations, C104- anions, and chloroform molecules. A stereoscopic crystal packing diagram is given in Figure 1. The [Co(CNCsHs)s]+ ion, shown in Figure 2, has squarepyramidal geometry. The square pyramid is situated on the mirror plane such that there are only three crystallographically independent ligands: two basal and one apical. The atoms of the apical phenyl isocyanide, including all phenyl atoms, are constrained to be on the mirror plane. The apical Co-C distance is 1.88 (3) A, and the average basal Co-C distance is 1.84 (2) A. These bond distances and others are listed in Table V. The overall geometry of the [Co(CNCsHs)s]+ ion shows only very minor deviations from C4v symmetry. The four basal carbon atoms form almost a perfect square. The Co atom lies 0.37 (2) A above the plane formed by the basal carbons. This elevation above the plane is evident in the
c34043'
a
Distances 1.878 (27) N,-C,, 1.828 (21) N,-C,, 1.843 (20) N,-C,, 3.035 (15) c1,-0, 2.988 (21) c1,-0, 2.998 (15) ~1,-0, 1.696 (27) 1.682 (44) Angles 103.7 (11) Cl-Nl-Cll 99.9 (11) C,-N,-C,, 156.5 (10) C3-N3-C3, 86.0 (12) 0,
