47, 49 Ti NMR spectra of half‐sandwich titanium(IV) complexes

The 47, 49 Ti chemical shifts, resonance line half‐widths (Δν 1/2 ) and energies of the first electronic charge‐transfer transitions $(\lambda_{\max}^{\rm 1.CT})$ of Cp′TiX 3 , where Cp′ = η 5 ‐C 5 H 5 (Cp), η 5 ‐C 5 H 4 Me (MeCp), η 5 ‐C 5 HMe 4 (Me 4 Cp), η 5 ‐C 5 Me 5 (Me 5 Cp), η 5 ‐C 5 H 4 SiMe 3 (SiCp), η 5 ‐C 5 H 4 SnMe 3 (SnCp) and η 5 ‐C 5 H 4 SiMe 2 Cl (Si ′ Cp) and X = Cl, Br, I and OBu t , half‐sandwich complexes are reported. For the compounds studied, a direct linear relationship between δ( 49 Ti) and $\lambda_{\max}^{\rm 1.CT}$ was found. Copyright © 2004 John Wiley & Sons, Ltd.