refluxed and became dark brown and homogeneous over 2 h. The solution
was filtered, concentrated and cooled, affording brown crystals in 65%
yield. Analysis was satisfactory. EPR (X-band, THF, 77 K): g = 2.0, 8
lines.
very few vanadium(IV) imido complexes have been structurally
characterized.10 Perhaps more interestingly, of those that have,
none have been prepared from reduction of a diazo moiety. In
fact, of all reported vanadium imido complexes, only one other
is formed as the result of the reductive cleavage of a dinitrogen
analogue.11
Compound 1 has also shown reactivity with many other small
molecules such as tert-butyl isocyanide, 1,2-diphenylhydrazine
and organic aldehydes. Elucidation of other reaction products
and details of the reactivity of related compounds will be
reported elsewhere. Further development of chemistry at other
low-valent vanadium thiolate centers is under way.
For funding this work we thank the National Science
Foundation (Grant CHE-8857455). We also thank the National
Institutes of Health (Grant 1 S10 RR09008) and Boston College
for providing funds for the purchase of a Siemens SMART
single crystal X-ray diffractometer.
1 R. R. Eady, in Advances in Inorganic Chemistry, ed. A. G. Sykes,
Academic, San Diego, 1991, vol. 36, pp. 77–101 and references
therein.
2 S. M. Malinak, K. D. Demadis and D. Coucouvanis, J. Am. Chem. Soc.,
1995, 117, 3126.
3 W. C. A. Wilisch, M. J. Scott and W. H. Armstrong, Inorg. Chem., 1988,
27, 4333; C. R. Randall and W. H. Armstrong, J. Chem. Soc., Chem.
Commun., 1988, 986; L. Gelmini and W. H. Armstrong, J. Chem. Soc.,
Chem. Commun., 1989, 1904; M. J. Scott, W. C. A. Wilisch and W. H.
Armstrong, J. Am. Chem. Soc., 1990, 112, 2429; D. B. Sable and W. H.
Armstrong, Inorg. Chem., 1992, 31, 161; H. H. Murray, S. G. Novick,
W. H. Armstrong and C. S. Day, J. Cluster Sci., 1993, 4, 439; P. J.
Bonitatebus, Jr., S. K. Mandal and W. H. Armstrong, Chem. Commun.,
1998, 939.
4 J. J. H. Edema, S. Gambarotta, A. Meetsma, A. L. Spek and N.
Veldman, Inorg. Chem., 1991, 30, 2062.
Notes and References
5 D. W. Stephan and T. T. Nadasdi, Coord. Chem. Rev., 1996, 147, 147;
[V(pyt)3]2: G. Henkel, B. Krebs and W. Schmidt, Angew. Chem., Int.
Ed. Engl., 1992, 31, 1366; [V(tmeda)(pyt)2]: J. G. Reynolds, S. C.
Sendlinger, A. M. Murray, J. C. Huffman and G. Christou, Angew.
Chem., Int. Ed. Engl., 1992, 31, 1253; J. G. Reynolds, S. C. Sendlinger,
A. M. Murray, J. C. Huffman and G. Christou, Inorg. Chem., 1995, 34,
5745; [V(tmeda)(‘S4’)]: W. Tsagkalidis, D. Rodewald and D. Rehder,
J. Chem. Soc., Chem. Commun., 1995, 165.
6 Values for Cl (van der Waals) and V (atomic) taken from J. Emsley, The
Elements, Oxford University Press, Oxford, 1991, pp. 50, 210.
7 R. M. Catala, D. Cruz-Garritz, P. Sosa, P. Terreros, H. Torrens, A. Hills,
D. L. Hughes and R. L. Richards, J. Organomet. Chem., 1989, 359, 219;
R. M. Catala, D. Cruz-Garritz, A. Hills, D. L. Hughes, R. L. Richards,
P. Sosa and H. Torrens, J. Chem. Soc., Chem. Commun., 1987, 261;
Y. A. Simonov, A. A. Dvorkin, G. S. Matuzenko, M. A. Yampol’skaya,
T. S. Gifeisman, N. V. Berbeleu and T. I. Malinovskii, Koord. Khim.,
1984, 10, 1247; Y. A. Simonov, G. S. Matuzenko, M. M. Botoshanskii,
M. A. Yampol’skaya, N. V. Gerbeleu and T. I Malinovskii, Zh. Neorg.
Khim., 1982, 27, 407; M. J. Burk, R. H. Crabtree and E. M. Holt,
J. Organomet. Chem., 1988, 341, 495; J. M. Casas, L. R. Falvello, J.
Fornie´s and A. Martín, Inorg. Chem., 1996, 35, 56.
8 V. C. Gibson, C. Redshaw, L. J. Sequeira, K. B. Dillon, W. Clegg and
M. R. J. Elsegood, Chem. Commun., 1996, 2151.
9 D. E. Wigley, Prog. Inorg. Chem., 1995, 42, 239, and references therein;
W. A. Nugent and J. M. Mayer, Metal Ligand Multiple Bonds, John
Wiley and Sons, New York, 1988.
10 N. Wiberg, H.-W. Häring and U. Schubert, Inorg. Chem., 1978, 17,
1880; F. Preuss, H. Becker, J. Kaub and W. A. Sheldrick, Z.
Naturforsch., B: Anorg. Chem. Org. Chem., 1988, 43, 1195; S.
Gambarotta, A. Chiesi-Villa and C. Guastini, J. Organomet. Chem.,
1984, 270, C49; J. H. Osborne, A. L. Rheingold and W. C. Trogler,
J. Am. Chem. Soc., 1985, 107, 7945.
11 For compound [V(·NPh)Cl(µ-Cl)]2, M. Mazzanti, M. Khadkhodayan
and W. H. Armstrong, Abstracts of the 203rd National Meeting, ACS,
INOR No. 461, San Francisco, CA, 1992.
† E-mail: william.armstrong@bc.edu
‡ In a typical preparation, 5.372 g (30.00 mmol) of 2,6-dichlorothiophenol
(Lancaster) were added to 20 ml of toluene. 18.75 ml (30.00 mmol) of 1.6
M
n-butyllithium (Aldrich, in hexanes) were added over 0.5 h to the thiol
solution with vigorous stirring. The resulting white precipitate was washed
with hexane and dried, affording an approximately quantitative yield.
§ In a typical preparation, 1.00 g (2.82 mmol) of [VCl2(tmeda)2]4 was
dissolved in 20 ml of THF. Then 1.04 g (5.65 mmol) of LiDCTP were added
at once with stirring. The light blue solution turned homogeneous and
emerald green. Over 0.2 h a light green precipitate of [V(tmeda)(DCTP)2]
appeared. The precipitate was filtered off, washed with diethyl ether and
dried in vacuo to give analytically pure product in 68% yield. The yield
could be improved by treating the remaining filtrate with pentane. The green
precipitate was filtered off and rinsed with 5 ml of diethyl ether and then 5
ml of THF. The combined solids then afforded an 82% yield. Elemental
analysis was satisfactory. EPR (X-band, CH2Cl2, 77 K): g
multiline.
= 5.33,
¶ Crystal data for 1: a single crystal was mounted under the cold stream
(290 °C) of a Siemens SMART system. An initial collection of 60 frames
of data yielded the crystal system (hexagonal) and unit cell [a = 7.6735(1),
c = 65.3685(2) Å]. 20749 reflections were collected, of which 5003 were
unique. The space group (P61, Z = 6) was chosen by systematic absences
and successful refinement of the structure. No absorption correction was
used. The structure was solved using SHELX 5.0 using anisotropic thermal
parameters for all non-hydrogen atoms to values of R1 = 7.35%, wR2
=
15.7% for I > 2s(I). For 2·thf: a single crystal was mounted under the cold
stream (290 °C) of a Siemens SMART system. An initial collection of 60
frames of data yielded the crystal system (orthorhombic) and unit cell [a =
13.621(4), b = 15.254(4), c = 30.410(7) Å]. 17675 reflections were
collected, of which 10152 were unique. The space group (P212121, Z = 2)
was chosen by systematic absences and successful refinement of the
structure. No absorption correction was used. The structure was solved
using SHELX 5.0 using anisotropic thermal parameters for all non-
hydrogen atoms to values of R1 = 8.40%, wR2 = 13.72% for I > 2s(I).
CCDC 182/902.
∑ In a typical preparation, 0.25 g (0.478 mmol) of 1 was suspended with
stirring in 20 ml of THF. Addition of 0.044 g (0.239 mmol) of azobenzene
(Aldrich) yielded a yellow–green heterogeneous mixture which was then
Received in Bloomington, IN, USA, 5th January 1998; revised manuscript
received 27th May 1998; 8/04231D
1650
Chem. Commun., 1998