Organometallics
Article
residue was dissolved in a minimal amount of warm toluene and the
solution filtered through Celite. The toluene was removed in vacuo to
afford 101 mg (68% yield) of a yellow solid, which was washed with
diethyl ether and dried in vacuo. Crystals suitable for X-ray diffraction
were grown by vapor diffusion of pentane into a saturated benzene
solution at 23 °C. 1H NMR: δ 78.3 (v br, 6 CH3), 41.2 (br s, 4 CH),
2.4(1) μB. UV−vis (toluene; λ, nm (ε, M−1 cm−1)): 378 (2720).
Repeated analyses consistently yielded low values for C, as has been
observed in other NHC systems.21 Anal. Calcd for C44H54CoN4: C,
75.73; H, 7.80; N, 8.03. Found: C, 74.51; H, 7.52; N, 7.93.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work was supported by startup funding from the
University of Texas at San Antonio and by a grant from the
Welch Foundation (AX-1772 to Z.J.T.). We thank Mr.
Jonathan Caranto for assistance with EPR measurements.
−5.00 (br s, 24 o-Me), −5.87 (s, 12 p-Me), −6.02 (s, 8 m-H). μeff
=
[Co(CH2SiMe3)2(IPr)]. A flask was charged with 188 mg (182
μmol) of [Co2Cl2(μ-Cl)2(IPr)2] and 25 mL of diethyl ether. The
resulting blue suspension was briefly stirred and then chilled to −30
°C. To the chilled suspension was added 1.0 mL (1.0 mmol) of 1.0 M
Me3SiCH2MgCl. The suspension quickly became yellow and was
allowed to react for 5 min with warming to ambient temperature. All
volatiles were then removed in vacuo, and the resulting yellow residue
was extracted into pentane and the extract filtered through glass filter
paper. Evaporation of the pentane afforded 203 mg (89% yield) of a
yellow solid. Crystals suitable for X-ray diffraction were grown by slow
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ASSOCIATED CONTENT
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S
* Supporting Information
Figures S1−S15, Table S1, and CIF files containing additional
structures, spectra, and crystallographic data. This material is
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AUTHOR INFORMATION
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Corresponding Author
(29) Simms, R. W.; Drewitt, M. J.; Baird, M. C. Organometallics 2002,
21, 2958−2963.
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dx.doi.org/10.1021/om3010756 | Organometallics XXXX, XXX, XXX−XXX