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A. Antinolo et al. / Journal of Organometallic Chemistry 655 (2002) 63Á
/
69
˜
3.4. Synthesis of [Nb{Me2Si(h5-C5Me4)(h5-
C5H3SiMe3)}Cl2] (3a)
r.t. for 16 h. The solvent was removed under reduced
pressure and C6H5CH3 (50 ml) was added. The suspen-
sion was filtered and solvent removed in vacuo from the
filtrate yielding a yellow solid (0.83 g, 76%). IR (Nujol,
The synthesis of 3a was carried out in an identical
manner to 1a. [NbCl4(THF)2] (1.20 g, 3.17 mmol) and
Li2{Me2Si(C5Me4)(C5H3SiMe3)} (1.04 g, 3.17 mmol).
Yield: 1.25 g, 82%. IR (Nujol, cmꢁ1): nNbÃCl 307. Anal.
Calc. for C19H30Cl2NbSi2: C, 47.70; H, 6.32. Found: C,
47.41; H, 6.21%.
1
cmꢁ1): nCÅC 1720. H-NMR (200 MHz, C6D6): d 0.25
(3H), 0.26 (3H) (s, SiMe2), 0.82 (3H), 1.56 (3H), 1.78
(3H), 2.12 (3H) (s, C5Me4), 2.20 (3H), 2.45 (3H) (s,
MeCÅ
(m, C5H4). 13C{1H}-NMR (300 MHz, C6D6): d ꢁ
5.4 (SiMe2), 12.7, 13.4, 14.8, 16.1 (C5Me4), 11.7, 16.2
CMe), 99.3, 100.6, 103.6 (Cipso), 116.2, 124.2 (C5H4),
/
CMe), 4.86 (1H), 5.10 (1H), 5.12 (1H), 5.89 (1H)
/7.5,
ꢁ
/
3.5. Synthesis of [Nb{Me2Si(h5-C5Me4)(h5-
C5H3Pri)}Cl2] (4a)
(Å
/
123.4, 126.6, 126.9, 128.4, 129.6 (C5Me4), 127.0, 150.7 (Å
/
CMe). Anal. Calc. for C20H28ClNbSi: C, 56.54; H, 6.64.
Found: C, 56.30; H, 6.58%.
The synthesis of 4a was carried out in an identical
manner to 1a. [NbCl4(THF)2] (1.30 g, 3.43 mmol) and
Li2{Me2Si(C5Me4)(C5H3Pri)} (1.02 g, 3.43 mmol).
Yield: 1.08 g, 70%. IR (Nujol, cmꢁ1): nNbÃCl 305.
Anal. Calc. for C19H28Cl2NbSi: C, 50.90; H, 6.30.
Found: C, 50.65; H, 6.21%.
3.10. Synthesis of [Nb{Me2Si(h5-C5Me4)(h5-
C5H4)}Cl(PhCÅ
/
CPh)] (9a)
The synthesis of 9a was carried out in an identical
manner to 8a. Compound 1a (1.23 g, 3.03 mmol), NaÁ
/
3.6. Synthesis of [Nb{Me2Si(h5-C5Me4)(h5-
C5H3PPh2)}Cl2] (5a)
Hg (0.070 g, 3.03 mmol of Na) and PhCÅ
/
CPh (0.54 g,
3.03 mmol). Yield: 1.33 g, 80%. IR (Nujol, cmꢁ1): nCÅC
1734. H-NMR (200 MHz, C6D6): d 0.24 (3H), 0.27
1
The synthesis of 5a was carried out in an identical
manner to 1a. [NbCl4(THF)2] (1.40 g, 3.69 mmol) and
Li2{Me2Si(C5Me4)(C5H3PPh2)} (1.63 g, 3.69 mmol).
Yield: 1.61 g, 74%. IR (Nujol, cmꢁ1): nNbÃCl 271.
Anal. Calc. for C28H31Cl2NbPSi: C, 56.96; H, 5.29.
Found: C, 56.81; H, 5.22%.
(3H) (s, SiMe2), 1.01 (3H), 1.68 (3H), 1.77 (3H), 2.06
(3H) (s, C5Me4), 5.40 (1H), 5.45 (1H), 5.70 (1H), 5.75
(1H) (m, C5H4), 6.9Á
NMR (300 MHz, C6D6): d ꢁ
/
7.6 (s, 10H, PhCÅ
/
CPh). 13C{1H}-
/
1.3, ꢁ0.5 (SiMe2), 11.6,
/
12.2, 14.6, 15.7 (C5Me4), 96.5 (Cipso), 97.7, 110.6, 114.5,
121.5 (C5H4), 108.3, 111.2, 120.4, 131.8, 141.3 (C5Me4),
125.3, 127.8, 127.9, 128.5, 129.1, 129.2, 129.3, 129.4,
3.7. Synthesis of [Nb(h5-C5H4Pri)2Cl2] (6a)
129.7, 130.4, 132.1, 138.6 (Å
/
CPh), 150.3, 166.9 (Å
/
CPh).
Anal. Calc. for C30H32ClNbSi: C, 65.63; H, 5.87.
Found: C, 65.46; H, 5.88%.
The synthesis of 6a was carried out in an identical
manner to 1a. [NbCl4(THF)2] (1.40 g, 3.69 mmol) and
Li(C5H4Pri) (0.84 g, 7.38 mmol). Yield: 1.13 g, 81%. IR
(Nujol, cmꢁ1): nNbÃCl 300. Anal. Calc. for
C16H22Cl2Nb: C, 50.82; H, 5.86. Found: C, 50.70; H,
5.82%.
Acknowledgements
We gratefully acknowledge financial support from the
Direccio´n General de Ensenanza Superior e Investiga-
˜
3.8. Synthesis of [Nb(h5-C5H4PPh2)2Cl2] (7a)
cio´n Cient´ıfica, Spain (Grants. No. PB 98-0159-C02-01-
02 and No. BQU2000-0463) and funding for S.P. from
the FEDER project 1FD97-1375.
The synthesis of 7a was carried out in an identical
manner to 1a. [NbCl4(THF)2] (1.40 g, 3.69 mmol) and
Li(C5H4PPh2) (1.89 g, 7.38 mmol). Yield: 1.81 g, 74%.
IR (Nujol, cmꢁ1): nNbÃCl 275. Anal. Calc. for
C34H28Cl2NbP2: C, 61.65; H, 4.26. Found: C, 61.47;
H, 4.15%.
References
[1] G. Fink, R. Mulhaupt, H.H. Brintzinger (Eds.),Ziegler Catalysts,
¨
Springer-Verlag, Berlin, 1995.
3.9. Synthesis of [Nb{Me2Si(h5-C5Me4)(h5-
[2] E.W. Abel, F.G.A. Stone, G. Wilkinson (Eds.), in: M.F. Lappert
(Ed.), Comprehensive Organometallic Chemistry, 2nd ed., vol. 4,
Pergamon, Oxford, 1995.
C5H4)}Cl(MeCÅ
/
CMe)] (8a)
[3] (a) S.L.J. Conway, T. Dijkstra, L.H. Doerrer, J.C. Green, M.L.H.
Green, A.H.H. Stephens, J. Chem. Soc. Dalton Trans. (1998)
2689;
Compound 1a (1.04 g, 2.56 mmol) was added to Na
amalgam (0.058 g, 2.56 mmol of Na). To the mixture
was added THF (100 ml). To this stirred solution was
(b) J.H. Shin, G. Parkin, Chem. Commun. (1999) 887;
(c) H. Lee, B.M. Bridgewater, G. Parkin, J. Chem. Soc. Dalton
Trans. (2000) 4490.
added via microsyringe MeCÅ
/
CMe (0.20 ml, 2.56
mmol) and the reaction mixture was allowed to stir at