Organometallic Niobium and Tantalum Complexes
1H NMR: δ 1.75 [br, 6H, CH2(CH)2], 2.01 [br, 3H, CH(CH2)3], 2.21 [d, 6H,
4b: 0.5 g (1.1 mmol) [Cp*TaCl4] (in 20 mL toluene), 0.14 g (1.5
mmol) PH2Ph (in 5 mL toluene), yellow crystals from n-hexane,
yield: 0.57 g (95%). Mp: ca. 217°C (decomp.).
4
1
(CH2)3C, JPH ϭ 8 Hz], 2.30 (s, 15H, C5Me5), ca. 4.9 (d, 2H, PH2, JPH
ഠ340 Hz). 13C NMR: δ 14.3 (s, C5Me5), 29.3 [s, CH(CH2)3], 29.4 [s,
CH2(CH)2], 37.1 [s, (CH2)3C], 41.7 (s, C-PH2), 138.9 (s, C5Me5). 31P NMR:
δ ca. 16 (br).
Anal. Calcd for C16H22Cl4PTa (568.06): C, 33.8; H, 3.9; P, 5.5.
Found: C, 35.2; H, 4.2; P, 5.5%.
3a: 0.9 g (2.4 mmol) [Cp*NbCl4] (in 30 mL toluene), 0.35 g (2.9
mmol) PH2Cy, red crystals from n-pentane, yield: 1.1 g (95%). Mp:
ca. 212°C (decomp.).
1
1H NMR: δ 2.50 (s, 15H, C5Me5), ca. 5.9 (d, 2H, PH2, JPH ഠ360 Hz), 7.42
(br, 3H, o-H and p-H in Ph), 7.69 (br, 2H, m-H in Ph). 13C NMR: δ 14.1 (s,
C5Me5), 126.7 (s, m-C in Ph), 129.8 (s, p-C in Ph), 131.9 (s, o-C in Ph), 134.3
(s, C5Me5), 135.3 (s, ipso-C in Ph). 31P NMR: δ ca. Ϫ12 (br).
Anal. Calcd for C16H28Cl4PNb (486.06): C, 39.5; H, 5.8; P, 6.4.
Found: C, 40.2; H, 5.7; P, 6.2%.
5b: 0.6 g (1.3 mmol) [Cp*TaCl4] (in 20 mL toluene), 0.19 g (1.4
mmol) PH2Mes, yellow crystals from n-hexane, yield: 0.71 g (92%).
Mp: ca. 232°C (decomp.).
1H NMR: δ 0.86 (m, 2H, H4 in Cy), 1.28 (m, 4H, H3/H5 in Cy), 1.72 (m,
4H, H2/H6 in Cy), 2.22 (m, 1H, H1 in Cy), 2.30 (s, 15H, C5Me5), ca. 5.1 (d,
1
2H, PH2, JPH ഠ350 Hz). 13C NMR: δ 14.2 (s, C5Me5), 26.5 (s, C4 in Cy),
27.5 (d, C3/C5 in Cy, 3JPC ϭ 8.6 Hz), 32.2 (br, C2/C6 in Cy), 33.8 (br, C1 in
Cy), 138.7 (s, C5Me5). 31P NMR: δ ca. 5 (br).
Anal. Calcd for C19H28Cl4PTa (610.13): C, 37.4; H, 4.6; P, 5.1.
Found: C, 38.6; H, 4.1; P, 6.0%.
4a: 0.4 g (1.1 mmol) [Cp*NbCl4] (in 20 mL toluene), 0.12 g (1.3
mmol) PH2Ph, yellow crystals from n-hexane, yield: 0.48 g (96%).
Mp: ca. 212°C (decomp.).
1H NMR: δ 2.29 (s, 3H, p-Me in Mes), 2.51 (s, 15H, C5Me5), 2.58 (s, 6H, o-
1
Me in Mes), ca. 6.1 (d, 2H, PH2, JPH ഠ345 Hz), 6.93 (s, 2H, m-H in Mes).
13C NMR: δ 14.2 (s, C5Me5), 22.5 (s, p-Me in Mes), 25.2 (s, o-Me in Mes),
123.3 (s, m-C in Mes), 130.4 (s, p-C in Mes), 134.2 (s, C5Me5), 141.5 (s, o-C
in Mes), 143.8 (s, ipso-C in Mes). 31P NMR: δ ca. Ϫ40 (br).
Anal. Calcd for C16H22Cl4PNb (480.02): C, 40.1; H, 4.6; P, 6.5.
Found: C, 41.6; H, 4.8; P, 6.8%.
1H NMR: δ 2.30 (s, 15H, C5Me5), ca. 6.1 (d, 2H, PH2, 1JPH ഠ370 Hz), 7.44
(br, 3H, o-H and p-H in Ph), 7.70 (br, 2H, m-H in Ph). 13C NMR: δ 14.2 (s,
C5Me5), 127.0 (s, m-C in Ph), 129.8 (s, p-C in Ph), 131.3 (s, o-C in Ph), 134.4
(s, ipso-C in Ph), 138.7 (s, C5Me5). 31P NMR: δ ca. Ϫ12 (br).
X-ray Crystal Structure Determination of [Cp*TaCl4] and 1؊5:
˚
Data [λ(MoKα) ϭ 0.71073 A] were collected with a Siemens CCD
(SMART) diffractometer. All observed reflections were used for
refinement (SAINT) of the unit cell parameters. Empirical absorp-
tion correction with SADABS [47]. The structures were solved by
direct methods (SHELXTL PLUS) [48]. Nb, Ta, Cl, P and C atoms
were refined anisotropically; H atoms were located by difference
maps and refined isotropically for 1؊3 and 5. Due to disorder of
the phenyl ring in 4, no H atoms were refined for the phosphine
ligand. Table 3 lists crystallographic details. Crystallographic data
(excluding structure factors) for the structure reported in this paper
have been deposited with the Cambridge Crystallographic Data
Centre ([Cp*TaCl4]: CCDC 185935, 1a: CCDC 185927, 2a: CCDC
185937, 3a: CCDC 185930, 4a: CCDC 185931, 5a: CCDC 185934,
1b: CCDC 185932, 2b: CCDC 185928, 3b: CCDC 185929, 4b:
CCDC 185933, 5b: CCDC 185936). Copies of this information may
be obtained free of charge from The Director, CCDC, 12 Union
Road, Cambridge, CB2 1EZ, UK (Fax: ϩ44-1223-336033, e-mail:
5a: 0.4 g (1.1 mmol) [Cp*NbCl4] (in 20 mL toluene), 0.16 g (1.2
mmol) PH2Mes, yellow crystals from n-hexane, yield: 0.52 g (94%).
Mp: ca. 229°C (decomp.).
Anal. Calcd for C19H28Cl4PNb (522.09): C, 43.7; H, 5.4; P, 5.9.
Found: C, 42.6; H, 4.8; P, 6.6%.
1H NMR: δ 2.19 (s, 3H, p-Me in Mes), 2.31 (s, 15H, C5Me5), 2.36 (s, 6H, o-
1
Me in Mes), ca. 6.1 (d, 2H, PH2, JPH ഠ360 Hz), 6.92 (s, 2H, m-H in Mes).
13C NMR: δ 14.5 (s, C5Me5), 22.0 (s, p-Me in Mes), 24.7 (s, o-Me in Mes),
126.0 (s, m-C in Mes), 128.9 (s, p-C in Mes), 129.7 (s, o-C in Mes), 138.6 (s,
C5Me5), 143.0 (s, ipso-C in Mes). 31P NMR: δ ca. Ϫ40 (br).
1b: 1.5 g (3.3 mmol) [Cp*TaCl4] (in 30 mL toluene), 0.32 g (3.5
mmol) PH2But (in 5 mL toluene), yellow crystals from n-hexane,
yield: 1.74 g (96%). Mp: ca. 245°C (decomp.).
Anal. Calcd for C14H26Cl4PTa (548.07): C, 30.7; H, 4.8; P, 5.6.
Found: C, 30.8; H, 4.9; P, 5.3%.
Acknowledgment. We gratefully acknowledge financial support
from the Landesgraduiertenförderung Sachsen (S. B.) and thank H.
C. Starck GmbH & Co. KG for a generous donation of NbCl5
and TaCl5.
3
1H NMR: δ 1.48 (d, 9H, CMe3, JPH ϭ 12.7 Hz), 2.50 (s, 15H, C5Me5), ca.
1
4.9 (d, 2H, PH2, JPH ഠ300 Hz). 13C NMR: δ 13.4 (s, C5Me5), 30.7 (s,
CMe3), 33.2 (s, CMe3), 133.8 (s, C5Me5). 31P NMR: δ ca. 19 (br).
2b: 0.6 g (1.3 mmol) [Cp*TaCl4] (in 20 mL toluene), 0.31 g (1.9
mmol) PH2Ad (in 5 mL toluene), yellow crystals from n-pentane,
yield: 0.7 g (87%). Mp: ca. 237°C (decomp.).
References
Anal. Calcd for C20H32Cl4PTa (626.18): C, 38.4; H, 5.2; P, 4.9.
Found: C, 38.8; H, 5.4; P, 4.5%.
[1] Eds. E. W. Abel, F. G. A. Stone, G. Wilkinson, Comprehensive
Organometallic Chemistry II 1995, Volumes 4 and 5, Perga-
mon Press.
[2] (a) E. Hey-Hawkins, Chem. Rev. 1994, 94, 1661. (b) D. W.
Stephan, Angew. Chem. 2000, 112, 322. (and references there-
in).
[3] (a) E. Hey-Hawkins, K. Fromm, Polyhedron 1995, 14, 2825.
(b) R. Felsberg, S. Blaurock, s. Jelonek, T. Gelbrich, R.
Kirmse, A. Voigt, E. Hey-Hawkins, Chem. Ber./Recueil 1997,
130, 807.
[4] J. T. Scheper, K. C. Jayaratne, L. M. Liable-Sands, G. P. A.
Yap, A. L. Rheingold, C. H. Winter, Inorg. Chem. 1999, 38,
4354.
1H NMR: δ 1.75 [br, 6H, CH2(CH)2], 2.02 [br, 3H, CH(CH2)3], 2.20 [br, 6H,
1
(CH2)3C], 2.50 (s, 15H, C5Me5), ca. 4.8 (d, 2H, PH2, JPH ഠ320 Hz). 13C
NMR: δ 13.4 (s, C5Me5), 29.2 [s, CH(CH2)3], 29.3 [s, CH2(CH)2], 37.1 [s,
(CH2)3C], 41.9 (s, C-PH2), 133.7 (s, C5Me5). 31P NMR: δ ca. 15 (br).
3b: 0.7 g (1.5 mmol) [Cp*TaCl4] (in 20 mL toluene), 0.2 g (1.7
mmol) PH2Cy, yellow crystals from n-pentane, yield: 0.85 g (95%).
Mp: ca. 230°C (decomp.).
Anal. Calcd for C16H28Cl4PTa (575.10): C, 33.4; H, 4.9; P, 5.4.
Found: C, 32.7; H, 4.9; P, 5.8%.
1H NMR: δ 1.26 (m, 2H, H4 in Cy), 1.38 (m, 4H, H3/H5 in Cy), 1.77 (m,
4H, H2/H6 in Cy), 2.20 (m, 1H, H1 in Cy), 2.49 (s, 15H, C5Me5), ca. 5.0 (d,
1
2H, PH2, JPH ഠ360 Hz). 13C NMR: δ 13.3 (s, C5Me5), 23.3 (s, C4 in Cy),
[5] (a) J. C. Leblanc, C. Mo¨ıse, J. Organomet. Chem. 1989, 364,
C3. (b) R. T. Baker, J. C. Calabrese, R. L. Harlow, I. D. Willi-
ams, Organometallics 1993, 12, 830. (c) g. I. Nikonov, L. G.
3
2
27.6 (d, C3/C5 in Cy, JPC ϭ 8.5 Hz), 31.3 (d, C2/C6 in Cy, JPC ϭ 15.4
Hz), 33.8 (d, br, C1 in Cy, JPC ϭ 7 Hz), 133.5 (s, C5Me5). 31P NMR: δ ca.
1
7 (br).
Z. Anorg. Allg. Chem. 2002, 628, 2515Ϫ2522
2521