Collect. Czech. Chem. Commun. 2001, 66, 1375-1379
https://doi.org/10.1135/cccc20011375

Charge Distribution Within 1,2-Dicarba-closo-dodecaborane: Dipole Moments of Its Phenyl Derivatives

Drahomír Hnyka,*, Václav Všetečkab, Ladislav Drožb and Otto Exnerc

a Institute of Inorganic Chemistry, Academy of Sciences of the Czech Republic, CZ-250 68 Řež, Czech Republic
b Department of Organic Chemistry, Charles University, Hlavova 2030, CZ-128 40 Prague 2, Czech Republic
c Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, CZ-166 10 Prague 6, Czech Republic

References

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6a. Compounds 2a, 2b, 2c and 2d were prepared by allowing to react 6,9-bis(ligand)decaborane(12), 6,9-L2B10H12, where L was CH3CN, with a substituted phenylacetylene, 4-X-C6H4CCH (X = H, CH3, Br, Cl). See, e.g., Heying T. L., Ager J. W., Jr., Clark S. L., Mangold D. J., Goldstein H. L., Hillman M., Polak R. J., Szymanski J. W.: Inorg. Chem. 1963, 2, 1089. <https://doi.org/10.1021/ic50010a002>
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7. Dipole moments were measured at 25 °C in benzene (five solutions, weight fraction 1.8 · 10–4 to 1.1 · 10–3) by the method of Guggenheim and Smith8. Relative permittivities were measured at 6 MHz on a home-made DK-meter with direct frequency reading. Refractive indices were measured on an Aerograph refractive index detector (Varian). The following dipole moments were obtained: 1 4.50, 2a 4.94, 2b 5.32, 2c 3.66, 2d 3.64 and 2e 2.26 D; the estimated uncertainty was 0.05 D. For constructing Fig. 1, the following standard bond moments were used: H–Cal 0.3, H–Car 0, Car–Cl 1.6, Car–Br 1.57 and Car–NO2 4.0 D.
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