Multinuclear NMR study of some organoplatinum complexes containing multifunctional azines as chelating ligands

✍ Scribed by Dietrich Gudat; Akbey Dogan; Wolfgang Kaim; Axel Klein

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 172 KB
• Volume: 42
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1407

✦ Synopsis

Abstract

^1^H‐detected indirect NMR techniques were used to determine ^15^N and ^195^Pt NMR parameters for a series of organoplatinum(IV) complexes and one platinum(II) complex containing nitrogen‐based azobispyridine, bispyridyltetrazine, and bipyrimidine ligands. The inverse technique permitted the detection of small ^4^J(Pt,H) and ^5^J(Pt,H) long‐range couplings and the acquisition of ^15^N NMR data in natural isotopic abundance via ^n^J(N,H) intra‐ and inter‐ligand couplings, but failed in cases where coherence transfer is quenched by rapid relaxation of the metal atom. In one case, analysis of satellite patterns in a set of ^1^H,^15^N, ^1^H,^195^Pt and ^1^H,^13^C correlation spectra allowed a positive sign to be determined for ^1^J(Pt,^15^N). Qualitative arguments are presented to explain the observed ^15^N coordination shifts in complexes with different azine ligands in terms of azine–M dative bond formation and L~n~M–azine back‐donation. Copyright © 2004 John Wiley & Sons, Ltd.