Triphenylantimony(V) catecholato complexes with 4-(2,6-dimethylphenyliminomethyl)pyridine. Structure, redox properties: The influence of pyridine ligand

Publication date: Available online 21 June 2019Source: Journal of Organometallic ChemistryAuthor(s): Ludmila S. Okhlopkova, Andrey I. Poddel'sky, Ivan V. Smolyaninov, Georgy K. Fukin, Nadezhda T. Berberova, Vladimir K. Cherkasov, Gleb A. AbakumovAbstractThe complexation of triphenylantimony(V) catecholates (3,6-DBCat)SbPh3 (1), (4,5-pip-3,6-DBCat)SbPh3 (2) and (4,5-Cl2-3,6-DBCat)SbPh3 (3) with neutral 4-(2,6-dimethylphenyliminomethyl)pyridine (Py-CH=N–Ar) leads to the formation of hexacoordinated complexes (3,6-DBCat)SbPh3·(Py-CH=N–Ar) (4), (4,5-pip-3,6-DBCat)SbPh3·(Py-CH=N–Ar) (5) and (4,5-Cl2-3,6-DBCat)SbPh3·(Py-CH=N–Ar) (6) (where 3,6-DBCat is 3,6-di-tert-butyl-catecholate, 4,5-pip-3,6-DBCat is 4,5-(N,N′-piperazine-1,4-diyl)-3,6-di-tert-butyl-catecholate, 4,5-Cl2-3,6-DBCat is 4,5-dichloro-3,6-di-tert-butyl-catecholate) containing NPyridine-coordinated neutral donor ligand Py-CH=N–Ar. In the absence of donor ligands chlorine-containing catecholate 3 undergoes rearrangement in acetonitrile to form ionic complex [Ph4Sb]+[(4,5-Cl2-3,6-DBCat)2SbPh2]- (7). Complexes have been isolated and characterized by spectroscopic methods and cyclic voltammetry. The pyridine-containing catecholate (3,6-DBCat)SbPh3·Py (8) was also synthesized in order to compare it's the electrochemical behaviour with those of iminopyridine complexes 4–6. The presence of NPyridine-coordinated iminopyridine ligand changes the mechanism of catecholate oxidation in 4 and 6: the first oxidation...

Source: Journal of Organometallic Chemistry - June 22, 2019 Category: Chemistry Source Type: research