Chloro Titanium and Zirconium Complexes with [η5-Cyclopentadienyldi(silylamido)] Ligands
FULL PAPER
0.22 mmol, 65%). C9H15Cl5Si2Ti (404.5): calcd. C 26.72, H 3.74; (CDCl3, 20 °C): δ ϭ 0.13 (SiMe2), 0.64 (SiMe2), 1.65 (SiMe2), 2.65
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found C 27.00, H 3.73. H NMR (CDCl3, 20 °C): δ ϭ 0.76 (s, 6 (SiMe2), 32.1 (NCMe3), 64.6 (NCMe3), 113.1 (C5H3ipso), 129.4
H, SiMe2), 0.82 (s, 6 H, SiMe2), 7.33 (d, JH,H ϭ 1.8 Hz, 2 H, C5H3),
7.56 (t, JH,H ϭ 1.8 Hz, 1 H, C5H3) ppm. 13C NMR (CDCl3, 20
°C): δ ϭ 2.36 (SiMe2), 2.81 (SiMe2), 131.2 (C5H3), 135.0 (C5H3),
139.3 (C5H3ipso) ppm.
(C5H3), 130.6 (C5H3), 132.1 (C5H3), 135.5 (C5H3ipso) ppm.
[Zr{η5-C5H3(SiMe2Cl)2}Cl3] (8): In a sealed Schlenk tube, TiCl4
(0.18 mL, 1.65 mmol) was added by syringe to a cooled (Ϫ78 °C)
light yellow solution of complex 2 (0.43 g, 0.82 mmol) in toluene
(70 mL). The reaction mixture was then warmed to room tempera-
ture, followed by heating for 12 h to 110 °C. Volatiles were then
removed under vacuum and the residue extracted into hexane.
After filtration and removal of the solvent, complex 8 was isolated
as a light yellow solid (0.25 g, 0.56 mmol, 69%). C9H15Cl5Si2Zr
Method B: In a sealed Schlenk tube, an orange solution of TiCl4
(0.55 mL, 4.99 mmol) in toluene (15 mL) was cooled to Ϫ78 °C
and added to a cooled (Ϫ78 °C) stirred suspension of the lithium
salt 1 (0.55 g, 1.66 mmol) in the same solvent (50 mL). The reaction
mixture was then warmed slowly to room temperature and then
heated for 12 h to 110 °C. Volatiles were then removed under vac-
uum and the residue extracted into hexane to give 5 (0.66 g,
1.63 mmol, 60%).
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(447.9): calcd. C 24.14, H 3.38; found C 24.01, H 3.30. H NMR
(CDCl3, 20 °C): δ ϭ 0.70 (s, 6 H, SiMe2), 0.75 (s, 6 H, SiMe2), 6.76
(d, JH,H ϭ 1.8 Hz, 2 H, C5H3), 7.19 (t, JH,H ϭ 1.8 Hz, 1 H, C5H3)
ppm. 13C NMR(CDCl3, 20 °C): δ ϭ 2.65 (SiMe2), 3.83 (SiMe2),
121.4 (C5H3), 126.6 (C5H3ipso), 141.8 (C5H3) ppm.
Method C: Following the same procedure as method B, the similar
reaction of 1 with TiCl4 in hexane (15 mL), heating to 45 °C for
1 h, gave 5 in low yield (10%) after repeated extractions into hex-
ane.
[Zr{η5-C5H3 [SiMe2(NHtBu)](SiMe2-η1-NtBu)}Cl2(NMe2H)] (9):
A solution of [Zr{η5-C5H3 (SiMe2-η1-NtBu)2}(NMe2)] (0.74 g,
1.46 mmol) in toluene (40 mL) was added to a suspension of
NEt3·HCl (0.40 g, 2.92 mmol) in the same solvent. The resultant
mixture was then stirred for 2 h at 70 °C. The solvent was then
removed under vacuum and the residue extracted into pentane
(40 mL). After filtration and removal of the solvent, complex 9 was
isolated as an ochre microcrystalline solid (0.64 g, 1.21 mmol,
82%). C19H41Cl2N3Si2Zr (529.8): calcd. C 43.07, H 7.80, N 7.93;
[Ti{η5-C5H3[SiMe2(NHtBu)] (SiMe2-η1-NtBu)}Cl2] (6). ؊ Method
A: A solution of [Ti{η5-C5H3[SiMe2(NHtBu)](SiMe2-η1-NtBu)}-
(NMe2)2] (0.60 g, 1.30 mmol) in toluene (40 mL) was added to a
suspension of NEt3·HCl (0.35 g, 2.60 mmol) in the same solvent.
The mixture was then stirred for 12 h to 80 °C. After subsequent
removal of the solvent under vacuum, the residue was extracted
into pentane (70 mL). Following filtration and removal of the sol-
vent, complex 6 was then isolated as a red solid (0.54 g, 1.22 mmol,
94%). C17H34Cl2N2Si2Ti (441.4): calcd. C 46.26, H 7.76, N 6.35;
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found C 42.46, H 7.58, N 7.60. H NMR (C6D6, 20 °C): δ ϭ 0.27
(s, 3 H, SiMe2), 0.28 (s, 3 H, SiMe2), 0.5 (s, 3 H, SiMe2), 0.52 (s, 3
H, SiMe2), 1.06 (s, 9 H, NHCMe3), 1.50 (s, 9 H, NCMe3), 2.25 (s,
3 H, NMe2H), 2.27 (s, 3 H, NMe2H), 3.58 (s br, 1 H, NMe2H),
6.43 (m, 1 H, C5H3), 6.81 (m, 1 H, C5H3), 6.91 (m, 1 H, C5H3)
ppm. 13C NMR (C6D6, 20 °C): δ ϭ 1.1 (SiMe2), 1.4 (SiMe2), 1.9
(SiMe2), 4.2 (SiMe2), 31.6 (NHCMe3), 33.6 (NCMe3), 39.3 (br.,
NMe2H), 50.1 (NHCMe3), 58.3 (NCMe3), 114.6 (C5H3ipso), 123.9
(C5H3), 126.3 (C5H3), 127.9 (C5H3ipso), 129.4 (C5H3) ppm.
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found C 46.52, H 7.68, N 6.13. H NMR (C6D6, 20 °C): δ ϭ 0.24
(s, 3 H, SiMe2), 0.26 (s, 3 H, SiMe2), 0.45 (s, 3 H, SiMe2), 0.56 (s,
3 H, SiMe2), 1.05 (s, 9 H, NHCMe3), 1.38 (s, 9 H, NCMe3), 6.35
(m, 1 H, C5H3), 6.57 (m, 1 H, C5H3), 7.17 (m, 1 H, C5H3) ppm.
13C NMR (C6D6, 20 °C): δ ϭ Ϫ0.1 (SiMe2), 0.6 (SiMe2), 1.5
(SiMe2), 1.8 (SiMe2), 32.3 (NHCMe3), 33.9 (NCMe3), 49.8
(NHCMe3), 63.9 (NCMe3), 112.6 (C5H3ipso), 126.1 (C5H3), 129.4
(C5H3), 129.5 (C5H3ipso), 130.9 (C5H3) ppm.
[Zr{η5-C5H3[SiMe2(NHtBu)](SiMe2-η1-NtBu)}Cl(NMe2)]
(10):
SiClMe3 (15.2 µL, 0.12 mmol) was added by syringe to a solution
Method B: A solution of [Ti{η5-C5H3(SiMe2-η1-NtBu)2}(CH2Ph)]
(0.58 g, 1.25 mmol) in toluene (40 mL) was added to a suspension
of NEt3·HCl (0.34 g, 2.50 mmol) in the same solvent. The mixture
was then stirred for 12 h at 80 °C. The solvent was then removed
under vacuum and the residue extracted into hexane (40 mL). After
filtration and removal of the solvent, complex 6 was then isolated
as a red solid (0.31 g, 0.70 mmol, 70%).
of [Zr{η5-C5H3[SiMe2(NHtBu)](SiMe2-η1-NtBu)}(NMe2)2] (0.059 g,
1
0.12 mmol) in C6D6. The H NMR spectrum of this solution was
recorded after 1 h of reaction to confirm that 10 was the unique
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product. H NMR (C6D6, 20 °C): δ ϭ 0.30 (s, 3 H, SiMe2), 0.32
(s, 3 H, SiMe2), 0.44 (s, 3 H, SiMe2), 0.46 (s, 3 H, SiMe2), 1.04 (s,
9 H, NHCMe3), 1.27 (s, 9 H, NCMe3), 2.75 (d, 6 H, ZrNMe2),
6.28 (m, 1 H, C5H3), 6.52 (m, 1 H, C5H3), 7.02 (m, 1 H, C5H3)
ppm. 13C NMR (C6D6, 20 °C): δ ϭ 2.0 (SiMe2), 2.0 (SiMe2), 2.1
(SiMe2), 2.1 (SiMe2), 33.8 (NHCMe3), 34.1 (NCMe3), 43.3
(NMe2), 49.7 (NHCMe3), 56.9 (NCMe3), 111.6 (C5H3ipso), 122.6
(C5H3ipso), 122.9 (C5H3), 125.9(C5H3), 127.4 (C5H3) ppm.
Method C: 6 was formed when the method described below to pre-
pare 7 was followed, using 1 equiv. of TiCl4. The resulting mixture
contained 6 and 7 in a 1:3 molar ratio. Pure 6 could not be isolated
from this mixture.
[Ti{η5-C5H3(SiMe2Cl)(SiMe2-η1-NtBu)}Cl2] (7): In
Schlenk tube, an orange solution of TiCl4 (0.32 mL, 2.97 mmol) in
toluene (50 mL) was cooled to Ϫ78 °C and added to a cooled (Ϫ78
a
sealed
[Ti{η5-C5H3[SiMe2(NHtBu)](SiMe2-η1-NtBu)}Cl(CH2Ph)] (11): A
solution of [Ti{η5-C5H3(SiMe2-η1-NtBu)2}(CH2Ph)] (0.58 g,
1.25 mmol) in toluene (40 mL) was added to a suspension of
°C) stirred suspension of the lithium salt 1 (0.49 g, 1.48 mmol) in NEt3·HCl (0.17 g, 1.25 mmol) in the same solvent. The resultant
the same solvent (50 mL). NEt3 (0.62 mL, 4.45 mmol) was added
to this mixture, and finally, it was warmed to room temperature
and heated for 12 h to 110 °C. The volatiles were removed under
mixture was stirred for 2 h at 70 °C. The solvent was then removed
under vacuum and the residue was extracted into pentane (40 mL).
After filtration and removal of the solvent, complex 11 was isolated
vacuum and the residue was extracted into hexane. After filtration as a red solid (0.48 g, 0.96 mmol, 77%). C24H41ClN2Si2Ti (497.1):
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and removal of the solvent complex 7 was isolated as a yellow solid
calcd. C 57.99, H 8.31, N 5.64; found C 58.10, H 8.03, N 5.77. H
(0.44 g, 1.10 mmol, 75%). C13H24Cl3NSi2Ti (404.7): calcd. C 38.58, NMR (C6D6, 20 °C): δ ϭ 0.25 (s, 3 H, SiMe2), 0.30 (s, 3 H, SiMe2),
1
H 5.98, N 3.46; found C 39.07, H 6.16, N 3.46. H NMR (CDCl3, 0.40 (s, 3 H, SiMe2), 0.48 (s, 3 H, SiMe2), 1.04 (s, 9 H, NHCMe3),
20 °C): δ ϭ 0.60 (s, 3 H, SiMe2), 0.62 (s, 3 H, SiMe2), 0.70 (s, 3 H, 1.48 (s, 9 H, NCMe3), 2.92 (d, JH,H ϭ 9.6 Hz, 1 H, CH2Ph), 3.1
SiMe2), 0.79 (s, 3 H, SiMe2), 1.43 (s, 9 H, NCMe3), 6.53 (m, 1 H,
(d, 1 H, CH2Ph), 5.91 (m, 1 H, C5H3), 6.39 (m, 1 H, C5H3), 6.49
(m, 1 H, C5H3), 6.88 (m, 1 H, C6H5), 6.97 (m, 2 H, C6H5), 7.18
C5H3), 6.63 (m, 1 H, C5H3), 7.25 (m, 1 H, C5H3) ppm. 13C NMR
Eur. J. Inorg. Chem. 2004, 3074Ϫ3083
2004 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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