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Catalysts based on co-operating metal centres

The project concerns the production of catalysts with novel features and with potential use in the petroleum industry. This involves the synthesis of special bidentate organophosphorus ligands which co-ordinate with two or more metal atoms, which produce co-operative reactivity and thus enhance their catalytic properties (catalysts based on cooperating metal centres with early-late d-block transition metal complexes incorporating heterobinucleating ligands).

Synthetic methods to obtain heterobinucleating phosphines with additional hard donor atoms (oxygen, nitrogen and cyclopentadienyl), namely (oxymethyl)diphenylphosphine, bis(oxy- methyl)phenylphosphine, bis(oxymethylphosphino)methane, bis(phenylamino-methyl)- phenylphosphine, bis(o-carboxyphenylaminoethyl)phenylphosphine, (cyclopentadienyl)- phosphine and(2-cyclopentadienylethyl)phosphine have been developed. Coordinating ability of the phosphorus atom and the functional groups towards early-late d-block transition metals such as platinum, palladium, rhodium, titanium and zirconium have been studied, and complexes with coordination at the phosphorus atom (in particular bis(oxymethyl-phosphino)methane, bis((oxymethyl)phenylphospino)methane)-dichloroplatinum and palladium), as well as complexes with coordination at functional groups (2-cyclopenta-dienyl-2-chloro-5,7-diphenyl-1,3-dioxa-2-titano (and zircono-)-5,7-diphosphacyclo-octanes, dicyclopentadienyl(chloro)zirconyloxymethyl(diphenyl)phosphine, bis[n5-(di-phenylphosphino)cylopentadienyl]dichlorozirconium(IV), bis[n5,n5-phenylphosphino-(dicyclopentadienyl)]dichlorozirconium(IV)) were synthesised. The infrared (IR) and nuclear magnetic resonance (NMR) criteria to determine the type of coordination and configuration of the central metal atom were developed. The synthetic approaches to the hetero binuclear complexes were worked out and first example of heteropolynuclear system (cis-Bis(u-R,S-2,2-dicyclopentadienyl-5,7-diphenyl-1,3-dioxa-2-titano-5,7-diphosphacyclooctane)tetra-chlorodiplatinum(II)) has been obtained. The results will allow a number of novel binuclear and polynuclear complexes to be obtained with various early-late d-block transition metals and their structure, physical and chemical properties and catalytic activity can be studied.