Hawkeswood et al.
CHMe2, 1JP-C ) 53 Hz), 16.7. νN-P: 1135 cm-1. Anal. Calcd: H,
6.77; C, 46.53; N, 7.23. Found: H, 6.78; C, 46.63; N, 6.76.
Characterization data for 6 follow: green solid. Yield: 1.41 g, 75%.
1H NMR δ: 7.07 (d, 2H, No-Ph, 3JH-H ) 8 Hz), 6.96 (t, 2H, Nm-
recently drawn attention mainly as catalyst precursors for
the copolymerization of olefins.18
Experimental Section
3
3
Ph, JH-H ) 8 Hz), 6.71 (t, 1H, Np-Ph, JH-H ) 7 Hz), 1.05 (d,
3
27H, tBu, JP-H ) 14 Hz). 31P NMR δ: 64.4 (∆ν1/2 ) 625 Hz).
General Data. All preparations were performed under an
atmosphere of dry, O2-free N2 employing both Schlenk line
techniques and a Vacuum Atmospheres inert atmosphere glovebox.
Solvents were purified employing a Grubbs’ type solvent purifica-
tion system manufactured by Innovative Technology.19 All organic
1
13C NMR δ: 128.7, 125.2, 123.1, 42.1 (d, tBu, JP-C ) 40 Hz),
29.7. νN-P: 1122 cm-1. Calcd: H, 7.51; C, 50.36; N, 6.53. Found:
H, 7.86; C, 50.51; N, 6.10. Characterization data for 7 follow:
greenish brown solid. Yield: 1.37 g, 75%.1H NMR δ: 7.54 (dd,
1
reagents were purified by conventional methods. H and 13C{1H}
3
3
6H, Po-Ph, JH-H ) 8 Hz, JP-H ) 13 Hz), 6.91 (t, 3H, Pp-Ph,
3JH-H ) 8 Hz), 6.80 (m, 9H, Pm-Ph, Np-Ph, Nm-Ph), 3.99 (sep,
2H, CHMe2, JH-H ) 7 Hz), 1.14 (d, 12H, CHMe2, JH-H ) 7
Hz). 31P NMR δ: 20.4 (∆ν1/2 ) 532 Hz). 13C NMR δ: 133.4,
NMR spectra were recorded on Bruker Avance-300 and 500
spectrometers. All spectra were recorded in C6D6 at ambient
temperatures unless otherwise noted. Trace amounts of protonated
solvents were used as references, and chemical shifts are reported
relative to SiMe4. 31P{1H} NMR spectra were recorded on a Bruker
Avance-300, and chemical shifts are referenced to external 85%
H3PO4. Line widths at half height are reported in hertz. IR spectra
(Nujol mulls) were recorded on a Bruker Vector 22 FT-IR
spectrometer. Combustion analyses were done in house employing
a Perkin-Elmer CHN series 2400 analyzer. VOCl3, ArNCO (Ar )
Ph, C6H3-2,6-iPr2), Li[N(SiMe3)2], MeLi, and PhMgBr were used
as received from Sigma-Aldrich. VCl3(NPh) (2), VCl3(NC6H3-2,6-
iPr2) (3), and R3PNSiMe3 (R ) Ph, iPr, tBu) were prepared by
modified literature methods.12,20-22 In the case of a number of the
alkyl derivatives, difficulties in purification precluded elemental
analyses. In these cases, 1H NMR spectra for these compounds have
been deposited as Supporting Information. A few crystals of the
known compound [VCl(NPPh3)3]Cl (1)10 were obtained in low yield
from the reaction of Ph3PNSiMe3 and VOCl3 and grown in PhMe
at 25 °C.5
3
3
2
3
133.2 (d, Po-Ph, JP-C ) 11 Hz), 129.5 (d, (Pm-Ph, JP-C ) 13
Hz) 126.5, 122.8, 29.3, 24.4. νN-P: 1110 cm-1. Characterization
1
data for 8 follow: green solid. Yield: 2.06 g, 73%. H NMR δ:
7.01 (d, 2H, Nm-Ph, JH-H ) 8 Hz), 6.88 (t, 2H, Np-Ph, JH-H
7 Hz), 4.17 (sep, 2H, CHMe2, JH-H ) 7 Hz), 1.68 (d of sep, 3H,
CHMe2, JH-H ) 7 Hz, JP-H ) 11 Hz), 1.39 (d, 12H, CHMe2,
3JH-H ) 9 Hz), 0.77 (dd, 18H, CHMe2, 3JH-H ) 7 Hz, 3JP-H ) 16
Hz). 31P NMR δ: 56.3 (∆ν1/2 ) 609 Hz). 13C NMR δ: 144.4,
3
3
)
3
3
2
1
126.2, 122.8, 29.2, 26.2 (d, PCHMe2, JP-C ) 53 Hz), 24.5, 16.7.
ν
N-P: 1121 cm-1. Characterization data for 9 follow: green solid.
Yield: 2.02 g, 84%.1H NMR δ: 7.03 (d, 2H, Nm-Ph, JH-H ) 8
3
3
Hz), 6.89 (t, 1H, Np-Ph, JH-H ) 7 Hz), 4.10 (sep, 2H, CHMe2,
3JH-H ) 7 Hz) 1.41 (d, 12H, CHMe2, JH-H ) 7 Hz), 1.04 (d,
3
27H, tBu, JP-H ) 14 Hz). 31P NMR δ: 62.4 (∆ν1/2 ) 732 Hz).
3
13C NMR δ: 143.7, 126.0, 122.7, 45.6 (tBu, d, JP-C ) 41 Hz),
1
29.6, 29.3, 24.5. νN-P: 1115 cm-1
.
VMe2(NC6H3-2,6-iPr2)(NPtBu3) (10), VPh2(NPh)(NPtBu3) (11),
VPh2(NC6H3-2,6-iPr2)(NPiPr3) (12), and VPh2(NC6H3-2,6-iPr2)-
(NPtBu3) (13). Alkylation and arylation reactions were performed
in a similar manner using MeLi or PhMgBr and the appropriate
vanadium dichloride precursor; thus, only one preparation is
detailed. A solution of MeLi (0.46 mmol) in Et2O was added at
RT to a green solution of 8 (0.10 g, 0.18 mmol) in 30 mL of C6H6.
The resulting red solution was stirred for 1 h. The solvent was
removed in vacuo, and the product was extracted with hexane. The
solution was filtered through Hyflo Super Cel, and removal of the
hexane in vacuo afforded a red-brown solid. (0.070 g, 76%).
Characterization data for 10 follow. Yield: 0.070 g, 76%. 1H NMR
δ: 7.19 (d, 2H, Nm-Ph, 3JH-H ) 8 Hz), 6.99 (t, 1H, Np-Ph, 3JH-H
Synthesis of VCl2(NPh)(NPPh3) (4), VCl2(NPh)(NPiPr3) (5),
VCl2(NPh)(NPtBu3) (6), VCl2(NC6H3-2,6-iPr2)(NPPh3) (7), VCl2-
(NC6H3-2,6-iPr2)(NPiPr3) (8), and VCl2(NC6H3-2,6-iPr2)(NPt-
Bu3) (9). These compounds were prepared in a similar fashion from
2 or 3, and thus, one preparation is detailed. A solution of Ph3-
PNSiMe3 (1.41 g, 4.03 mmol) in 25 mL of PhMe was added at 25
°C to a burgundy solution of VCl3(NPh) (1.00 g, 4.03 mmol) in 40
mL of PhMe. The resulting burgundy solution was heated at reflux
for 24 h. The solvent was removed in vacuo, and the product was
washed with hexanes (4 × 15 mL). Drying in vacuo for 5 h afforded
a brown solid (1.41 g, 72%). Characterization data for 4 follow.
1H NMR δ: 7.49 (dd, 6H, Po-Ph, 3JH-H ) 8 Hz, 3JP-H ) 13 Hz),
3
3
3
) 8 Hz), 4.22 (sep, 2H, CHMe2, JH-H ) 7 Hz), 1.46 (d, 12H,
6.94 (t, 3H, Pp-Ph, JH-H ) 6 Hz), 6.83 (dt, 6H, Pm-Ph, JH-H
)
3
4
CHMe2, JH-H ) 7 Hz), 1.39 (s, 6H, CH3), 1.08 (d, 27H, t-Bu,
7 Hz, JH-H ) 3 Hz), 6.63 (m, 4H, No-Ph, Nm-Ph), 6.56 (m, 1H,
3JP-H ) 14 Hz). 31P NMR δ: 46.4 (∆ν1/2 ) 931 Hz). 13C NMR δ:
Np-Ph, JH-H ) 5 Hz). 31P NMR δ: 22.6 (∆ν1/2 ) 605 Hz). 13C
3
1
2
142.4, 128.3, 122.9, 122.5, 41.3 (d, tBu, JP-C ) 45 Hz), 29.6,
NMR δ: 133.0, 132.9 (d, Po-Ph, JP-C ) 11 Hz), 129.2 (d, Pm-
Ph, JP-C ) 13 Hz), 128.0, 125.4, 124.2. νN-P: 1132 cm-1. Anal.
3
29.2, 24.4. Characterization data for 11 follow: red solid. Yield:
3
0.028 g, 48%.1H NMR δ: 8.57 (d, 4H, Vo-Ph, JH-H ) 7 Hz),
Calcd: H, 4.12; C, 58.92; N, 5.73. Found: H, 4.31; C, 58.27; N,
5.35. Characterization data for 5 follow: green solid. Yield: 2.43
3
7.44 (d, 2H, No-Ph, JH-H ) 8 Hz), 7.18 (m, 8H, Vm-Ph, Vp-Ph,
3
1
3
Nm-Ph), 6.87 (t, 1H, Np-Ph, JH-H ) 7 Hz), 1.09 (d, 27H, tBu,
g, 78%. H NMR δ: 7.11 (d, 2H, No-Ph, JH-H ) 8 Hz), 6.94 (t,
3JP-H ) 13 Hz). 31P NMR δ: 52.7 (∆ν1/2 ) 1192 Hz). 13C NMR
3
3
2H, Nm-Ph, JH-H ) 8 Hz), 6.72 (t, 1H, Np-Ph, JH-H ) 7 Hz),
1
3
2
δ: 136.1, 129.0, 127.0, 124.0, 122.4, 40.3 (d, tBu, JP-C ) 43.5
1.73 (d(sep), 2H, CHMe2, JH-H ) 7 Hz, JP-H ) 11 Hz), 0.78
(dd, 18H, CHMe2, JH-H ) 7 Hz, JP-H ) 17 Hz). 31P NMR δ:
3
3
Hz), 29.3. Characterization data for 12 follow: red solid. Yield:
1
3
56.9 (∆ν1/2 ) 702 Hz). 13C NMR δ: 128.7, 125.6, 123.5, 25.4 (d,
0.021 g, 36%. H NMR δ: 8.34 (d, 4H, Vo-Ph, JH-H ) 7 Hz),
7.45 (d, 2H, Nm-Ph, 3JH-H ) 7 Hz), 7.16 (m, 6H, Vm-Ph, Vp-Ph),
3
3
6.98 (t, 1H, Np-Ph, JH-H ) 7 Hz), 4.46 (sep, 2H, CHMe2, JH-H
) 6.24 Hz), 1.73 (d(sep), 3H, CHMe2, 3JH-H ) 7 Hz, 2JP-H ) 11
Hz), 1.28 (d, 12H, CHMe2, 3JH-H ) 7 Hz), 0.86 (dd, 18H, CHMe2,
(18) Arndt-Rosenau, M.; Hoch, M.; Sundermeyer, J.; Kipke, J.; Lemke,
M. (Bayer AG, Germany) Eur. Pat. Appl. Ep, 2003, p 17 pp.
(19) Pangborn, A. B.; Giardello, M. A.; Grubbs, R. H.; Rosen, R. K.;
Timmers, F. J. Organometallics 1996, 15, 1518.
3JP-H ) 15 Hz). 31P NMR δ: 40.5 (∆ν1/2 ) 668 Hz). 13C NMR δ:
(20) Devore, D. D.; Lichtenhan, J. D.; Takusagawa, F.; Maatta, E. A. J.
Am. Chem. Soc. 1987, 109, 7408-7416.
1
143.7, 135.9, 127.0, 123.7, 122.7, 28.3, 25.8 (d, CHMe2, JP-C
)
(21) Buijink, J.-K. F.; Meetsma, A.; Teuben, J. H.; Kooijman, H.; Spek,
A. L. J. Organomet. Chem. 1995, 497, 161-170.
56.8 Hz), 24.7, 16.8. Characterization data for 13 follow: red solid.
1
Yield: 0.025 g, 44%. Crystals grew from hexane at -30 °C. H
(22) Birkofer, L.; Kim, S. M. Chem. Ber. 1964, 97, 2100-2101.
3
NMR δ: 8.32 (d, 4H, Vo-Ph JH-H ) 7 Hz), 7.22 (d, 4H, Nm-Ph
5430 Inorganic Chemistry, Vol. 42, No. 17, 2003