STRUCTURE AND CATALYTIC ACTIVITY OF RHODIUM COMPLEX COORDINATED ON 2-VINYLPYRIDINE-METHYL ACRYLATE COPOLYMER FOR THE CARBONYLATION OF METHANOL

A series of rhodium complexes coordinated on the hybrid ligand. 2-vinylpyridine-methyl acrylate copolymers, as catalyst for the carbonylation of methanol were synthesized by the reaction of the copolymers with tetracarbonyldichlorodirhodium. These complexes were in general very reactive in carbonylation of methanol to form acetic acid and methyl acetate without other by-product. The XPS studies of the complexes showed that the binding energies of Nls(399.1-399.4 eV) and that of Ols(532.5-532.9 eV) were higher than that of the copolymer ligand (Nls 398.1-398.3 eV and Ols 532.2-532.3 eV), indicating the fromation of N→Rh and O→Rh coordination bonds. The IR spectra of complexes showed that the appearance of two absorption peaks of terminal carbonyl at 1990-2100 cm~(-1), characteristic of the cis-dicarbonyl rhodium moiety. These XPS and IR studies confirm the formation of cis-dicarbonylrhodium complex with the active centers(A) and (B) as shown in the text. The increase of activity of the complex in the c