Multinuclear NMR study of Au(I), Pd(II) and Ag(I) pyrazole complexes to investigate the coordination mode

Abstract

The coordination effects induced on the 1H-, 13C-, and 15N- NMR chemical shifts of the 3,5-di-(4-butoxyphenyl)-1H- pyrazole, HPzbp2 (1) have been quantified for the following complexes:- [Au(HPzbp2)(PPh3)](NO3) (2), [Pd(η3-C 3H5)(HPzbp2)2](BF4) (3) [or Pd(η3-C3H5)(15N2-HPz bp2)2](BF4) (15N2-3)], and [Ag( HPzbp2)2](BF4) (4), in solution and in the solid state. 15N-CPMAS NMR proved to be the most useful tool for establishing the coordination site. The increase in the nitrogen-shielding on metal-complexation owing to changes in the paramagnetic shielding term is about -55 ppm. © ARKAT.