1,2-Metallotropic shifts in tricarbonylrhenium(I) complexes of pyridazine (pydz): a dynamic NMR investigation of the effects of cis-chelating ligands

Author(s): Abel | Edward. W | Heard Peter. J | Orrell | Keith. G

Type of publication: Journal paper

Abstract: Complexes of general formula fac-[Re(CO)3(L-L)(pydz) [BF4] (L-L=neutral bidentate chelate ligand; pydzspyridazine) were prepared in high yield from fac-[ReBr(CO)3(L-L)]. The pyridazine ligand coordinates to the metal moiety in a monodentate fashion, and undergoes a facile intramolecular 1,2-Re-N shift. The kinetics of the 1,2-metallotropic shift were measured by either one-dimensional NMR bandshape analysis or two dimensional exchange spectroscopy. The free energies of activation, △G≠ (298 K), were found to be dependent on the nature of the chelate ligand, and were in the range 77-87 kJ moly-1. The origins of the chelate ligand effects are discussed.

Published URL: https://www.sciencedirect.com/science/article/abs/pii/S002016939605339X

Date Published: January 2 1997

Publisher: Elsevier

Place of publication: United Kingdom

Pages: 65-71

Subject(s): Chemistry

DOI: https://doi.org/10.1016/S0020-1693(96)05339-X

Keywords: Chemistry | Pyridazine | Ligands | Metallotropic shifts

Depositing User: Victoria Rendell