45934-AC5
Elucidating Catalytic Cycles of Supported Molecular Metal Complexes
Dealuminated Y zeolite was used as a support for a family of mononuclear ruthenium complexes formed from cis-Ru(acac)2(C2H4)2. Infrared (IR) and extended X-ray absorption fine structure (EXAFS) spectroscopies were used to characterize the supported species. Changes in the Si:Al ratio of the zeolite influence the chemistry of the supported ruthenium complex, as acac ligands of the Ru(acac)(C2H4)22+ species are dissociated and captured by Al3+ sites of the zeolite. Samples have been prepared that contain both physisorbed precursor and chemisorbed complexes formed from it. The chemisorbed complexes catalyze ethene dimerization, and the reaction is promoted by H2 and by Al3+ centers of the zeolite. Details of the chemistry are being elucidated.
