Communications
equivalent of (I2P)2(C6H8) and one equivalent of (I2P)2CPh2
(d(31P) = 138.34 and 133.95 ppm in C6D6, see the Supporting
Information, Figure 11s and 12s).[25–27] This reactivity mimics
that which might be expected for a functionalized P4
molecule.[28] Consistent with the electrochemistry data, we
were unable to effect cluster reduction of 4 using a variety of
reducing agents, and all of the observed oxidation chemistry
resulted in fragmentation as described for I2.
[1] CCDC-696072 contains the supplementary crystallographic data
for this paper. These data can be obtained free of charge from
The Cambridge Crystallographic Data Centre via www.ccdc.
[2] W. A. Nugent, J. M. Mayer, Metal-Ligand Multiple Bonds, Wiley
Interscience, New York, 1988.
[5] J. S. Figueroa, N. A. Piro, C. R. Clough, C. C. Cummins, J. Am.
[6] N. A. Piro, J. S. Figueroa, J. T. McKellar, C. C. Cummins, Science
[8] C. R. Clough, J. B. Greco, J. S. Figueroa, P. L. Diaconescu, W. M.
[15] B. M. Cossairt, C. C. Cummins, Inorg. Chem. 2008, DOI:
10.1021/ic8009282.
[17] N. Huy, Y. Inubushi, L. Ricard, F. Mathey, Organometallics 1997,
16, 2506.
[19] E. V. Anslyn, D. A. Dougherty, Modern Physical Organic
Chemistry, University Science Books, Sausalito, 2004.
[23] J. D. Masuda, W. W. Schoeller, B. Donnadieu, G. Bertrand,
This work has demonstrated the use of a metal-complexed
phosphorus cluster as a starting point for the synthesis of
phosphorus-rich organic molecules. These organophosphanes
represent a new and unique class of phosphorus clusters
bearing cyclic olefins as substituents as well as a cluster-
incorporated carbene unit. The robust nature of these
clusters, both thermally and chemically, makes them poten-
tially attractive as main-group precursors to phosphorus-rich
materials. Additionally, this work exemplifies the natural
nexus of main-group and transition-metal chemistry by
demonstrating the synthesis of unique main-group species
using concepts and methods provided by transition-metal
chemistry.
Experimental Section
4: [Ph2CP8Nb(OC[Ad]Mes)3] (1.448 g, 1 equiv) was suspended in
Et2O (60 mL). Cyclohexadiene (1.72 g, 20 equiv) was added to the
stirred suspension. To this mixture was added pyridine-N-oxide
(305 mg, 3 equiv) as a solid. The mixture was allowed to stir for 10 h.
After this time there was a gray-white precipitate that had formed.
The precipitate, a gray solid (presumably the untrapped material) was
removed by filtering the reaction mixture through a pad of Celite. An
aliquot from the reaction filtrate was taken for 1H NMR analysis and
revealed only two species, the oxoniobium complex 3 and compound
4. The filtrate was dried and then slurried in Et2O (20 mL), resulting
in formation of an off-white precipitate. This precipitate was isolated
on a frit, washed with Et2O (50 mL) and pentane (20 mL) and dried
under reduced pressure resulting in 203 mg (38% yield). The filtrate
was concentrated and placed in the glovebox freezer for additional
crops resulting in an additional 51mg of white powder. Yield: 254 mg
(48% yield); 1H NMR (208C, 500 MHz, C6D6): d = 0.78 (br, 2H), 1.06
(br, 2H), 2.54 (br, 2H), 5.80 (ꢀ q, 2.74 Hz, 2H), 6.89 (m, 6H), 7.55 (d,
7.53 Hz, 4H); 13C NMR (208C, 126 MHz C6D6): d = 24.6 (m, CH2),
30.8 (m, CH), 39.4 (m, PCP), 128.7 (s, Ar), 128.9 (s, Ar), 128.9 (s, Ar),
[24] J. D. Masuda, W. W. Schoeller, B. Donnadieu, G. Bertrand, J.
132.1 (br, C C), 145.0 (s, Ar); 31P NMR (208C, 202 MHz, C6D6): d =
=
[25] J. G. Verkade, L. D. Quin, Phosphorus-31 NMR Spectroscopy in
Spectrochemical Analysis, Vol. 8, VCH, Deerfield Beach, 1987.
[26] L. D. Quin, J. G. Verkade, Phosphorus-31 NMR Spectral Proper-
ties in Compound Characterization and Structural Analysis,
VCH, New York, 1994.
À173.2 (t, 230 Hz, 2P), À124.0 (t, 245 Hz, 1P), 39.3 (pseudo d, 220 Hz,
2P), 48.3 (t, 327 Hz, 1P), 57.2 ppm (m, 2P). Elemental analysis calcd.
for C19H18P8: C 46.16, H 3.67; found: C 46.88, H 4.05. m.p.: 165–1688C
(dec).
[27] L. D. Quin, A Guide to Organophosphorus Chemistry, Wiley
Interscience, New York, 2000.
Received: August 11, 2008
Published online: October 15, 2008
Keywords: cluster compounds · Diels–Alder reaction ·
.
diphosphenes · niobium · phosphorus
ꢀ 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2008, 47, 8863 –8866