3030 Inorg. Chem. 1987, 26, 3030-3034 inspection of Table VI reveals that AEQ values increase steadily In summary, a combination of susceptibility and Mossbauer as the precentage of S = 3/2 character increases. We have noted studies and a knowledge of structure lead to a good quantitative previously the correlation of large AEQ with small spin-orbit description of the magnetic properties of intermediate-spin iron- coupling ({) and small hyperfine field (pK/g~&).~"The results (111) porphyrins. Previously unrecognized intermolecular anti- suggest that the carborane ligand is a stronger field ligand than ferromagnetic coupling of moderate magnitude seems to be the hexafluoroantimonate since they analyze for 92 and 98% S = 3/2, rule rather than the exception in five-coordinate complexes, respectively. This is interesting because viewing their structures particularly when association into dimers occurs in the crystal solely in the context of spin state would lead to the opposite lattice. The question of spin coupling among six-coordinate conclusion. The Fe-N bond lengths and the Fe out-of-plane porphyrin complexes remains open since coupling involving more displacements1' are smaller for the carborane than for the hex- than a pair of lattice sites does not provide an easily identified afluoroantimonate, as expected for a lower S = 5/2 contribution. signature in the Mossbauer spectrum. An explanation lies in the interplay of field strengths and binding strength and reminds us that these factors are not synonymous Acknowledgment. We thank the National Institutes of Health nor necessarily correlated. The pr donor capability of the fluoride for support of this work under Grants HL-16860 (G.L.) and donor apparently makes SbF, a weaker field ligand than BIICH,< GM-38401 (W.R.S.) and the National Science Foundation for despite the stronger binding indicated in the structural comparison. the support under Grant CHE85-19913 (C.A.R.). The carborane is not capable of pr donation. If the two anions were hypothetically assumed to have equal u-donor interactions, Registry No. [Fe(TPP)(B,,CH,,)]C,H~, 102 149-51-9; Fe(TPP)Br, 25482-27-3. then the SbF6- coordination parameters would be expected to be the same as or smaller than B11CH12-. That they are larger Supplementary Material Available: For [Fe(TPP)(Bl,CH12)]C7H,, indicates that the a-donor interaction of SbF,- is considerably Table IS (magnetic measurements), Tables IIS and IIIS (fixed atomic greater than that of Bl,CHl,-. This further supports the hy- coordinates), and Table IVS (anisotropic temperature factors) (5 pages); pothesis" that BIICHIZ-is the lesser coordinating of these two a listing of observed and calculated structure amplitudes (XlO) (25 anions. pages). Ordering information is given on any current masthead page. Contribution from the Department of Chemistry and the Molecular Structure Center, Indiana University, Bloomington, Indiana 47405 Direct Synthesis of VE2+ (E = S, Se) Complexes Using Elemental Chalcogens. Preparation, Structure, and Properties of [VS(SPh),12- and [VSe(edt),12- (edt2- = Ethane-1,2-dithiolate) John R. Nicholson,la John C. Huffman,lb Douglas M. Ho,lb and George Christou*>+J" Received April 7, I987 The reaction of elemental sulfur or selenium with VCI3/sodium thiolate reaction mixtures in MeCN provides a convenient and direct route to mononuclear complexes containing the VE2+ (E = S, Se) moiety. The preparation of complexes containing the [VS(SPh),12-, [VSe(SPh)4J2-,or [VSe(edt),12- dianion is described. [PhCH,NMe3l2[VS(SPh),1 (1) crystallizes in monoclinic space group P2, with unit cell dimensions (at -156 "C) of a = 10.312 (4) A, 6 = 16.293 (6) A,c = 13.930 (6) A,p = 117.57 (2)", and Z = 2. The anion contains a vanadium(1V) center in its characteristic square-pyramidal geometry with a multiply bonded S atom in the apical position and four benzenethiolate S atoms in the basal positions. The V=S bond length is 2.078 (2) A. (NEt,),[VSe(edt),] (3) crystallizes in orthorhombic space group P2,ab with unit cell dimensions (at -155 "C) of a = 15.005 (4) A,b = 12.769 (3) A, c = 14.248 (3) A,and Z = 4. Again, the vanadium(1V) center has square-pyramidal geometry with a multiply bonded Se atom in the apical position and four thiolate S atoms from two chelating edt2- groups occupying the basal positions. Complex 3 is the first structurally characterized example of a %e2+ species. The V=Se bond length is 2.196 (3) A. Complex 1 is only the third example of a structurally characterized VS2+species. A linear relationship has been found to exist between the bond length and the 1R stretching frequency of the the V=S unit. Introduction search. As we describe below, this objective has been realized. Research in this group is directed toward the development of We have also extended it and developed a direct route to complexes discrete metalsulfide-thiolate chemistry for an early 3d transition containing the extremely rare [V=SeI2+ unit, and describe the metal, namely vanadium. Preliminary progress has been the first structural characterization of such a species. subject of several recent reports,*-' and we now have V/S/SR Experimental Section species spanning the oxidation level range 111-V and nuclearities Syntheses. All manipulations were performed by using standard in- of 1-4. In one of these reports2 we described how the oxo- ert-atmosphere techniques and a purified dinitrogen atmosphere. MeCN vanadium(1V) complex [V0(edt),l2- could be converted to the (CaH,) and Et;O (Na/benzophenone) were purified by distillation and sulfur analogue [VS(edt)J2- by treatment with (Me3Si)2S. While thoroughly degassed before use. Dry NaSPh and Na,edt were prepared pure product was obtained, its yield was relatively low (34%) and, of course, this procedure required prior preparation the oxo of (1) (a) Department of Chemistry. (b) Molecular Structure Center. complex. As we continued to extend our studies of V/S/SR (2) Money, J. K.; Huffman, J. C.; Christou, G. Inorg. Chem. 1985, 24, chemistry, it was recognized that a direct synthetic route to 3297. thiovanadium(1V) complexes could make available large quantities (3) Money, J. K.; Folting, K.; Huffman, J. C.; Collison, D.; Temperley, .I.; and allow future reactivity studies of these highly reactive materials Mabbs, F. E.; Christou, G. Inorg. Chem. 1986, 25, 4583. (4) Money, J. K.; Nicholson, J. R.; Huffman, J. C.; Christou, G. Inorg. to be more conveniently performed. We thus decided to seek such Chem. 1986, 25, 4072. a direct synthetic procedure and herein report the results of this (5) Money, J. K.; Huffman, J. C.; Christou, G. J. Am. Chem. Sor. 1987, 109, 2210. (6) Money, J. K.; Folting, K.; Huffman, J. C.; Christou, G. Inorg. Chem. 1987, 26, 944. 'Alfred P. Sloan Research Fellow, 1987-1989 (7) Money, J. K.; Huffman, J. C.; Christou, G., submitted for publication. 0020-1669/87/ 1326-3030$01.50/0 0 1987 American Chemical Society Direct Synthesis of VE2+ (E = S, Se) Complexes Inorganic Chemistry, Vol. 26, No. 18, 1987 3031 from the thiol and Na metal in THF; the resulting white powder was Table 1. Crystallographic Data for Complexes 1 and 3 collected by filtration, washed well with THF, and dried in vacuo. VCI, was used as received. param 1 3 (PhCH2NMe3),[VS(SPh),] (1). A stirred slurry of NaSPh (6.60 g, formula CP&~N~SSV.. C20H48N2S4SeV 50 mmol) and (PhCH2NMe3)CI(3.70 g, 20 mmol) in MeCN (70 mL) M, 820.18 574.79 was treated with solid VCI, (1.57 g, IO mmol). Initially, a dark brown cryst syst monoclinic orthorhombic coloration was observed, but this converted to an orange powder after ca. space group p21 P2,ab 2 min, presumably a polymeric V/SPh species. Addition of sulfur (0.32 temp, "C -156 -155 g, 10 mmol) caused the rapid formation of an intense orange-brown a, .A 10.312 (4)" 15.005 (4)b solution and dissolution of the majority of the solid material. After being b, A 16.293 (6) 11.769 (3) stirred a further 2 h, the solution was filtered and Et20(35 mL) added c, A 13.930 (6) 14.248 (3) to yield a dark brown oil that crystallized on agitation. After storage in A deg 177.57 (2) ... a freezer overnight, the solid was collected by filtration, washed with z 2 4 MeCN/Et20 (1:2), and dried in vacuo. The filtrate was left undisturbed vol, A3 2074.76 2729.94 at ambient temperature for several days, and a second crop of well- A(Mo Ka),' 8, 0.71069 0.71069 formed crystals was isolated as above. The majority product, the first abs coeff 5.072 19.764 crop, was repeatedly found by IR spectroscopy to be contaminated with cryst size, mm 0.18 X 0.18 X 0.25 0.13 X 0.15 X 0.20 relatively small, but nevertheless significant, amounts of an unidentified scan speed, deg/min 4.0 4.0 component, and attempted purification by recrystallization was unsuc- scan width, deg 1.6 + dispersion 2.0 + dispersion cessful due to the instability of 1 on redissolution. The second crop, scan range, deg 6 5 28 5 45 6 5 28 I45 representing an overall yield of -lo%, was found to be analytically pure tot. no. of data 4104 2107 and suitable for structural studies and was used for product characteri- no. of unique data 2836 1882 zation. Anal. Calcd for C44H52N2SSV:C, 64.4; H, 6.4; N, 3.4. Found: av R 0.02Sd e C, 64.5; H, 6.4; N, 3.4. v(VS) = 521 cm-'.