A fully heterogeneous and highly efficient dual catalyst system for alkane metathesis (AM) has been developed. The system is comprised of an alumina-supported iridium pincer catalyst for alkane dehydrogenation/olefin hydrogenation and a second heterogeneous olefin metathesis catalyst. The iridium catalysts bear basic functional groups on the aromatic backbone of the pincer ligand and are strongly adsorbed on Lewis acid sites on alumina. The heterogeneous systems exhibit higher lifetimes and productivities relative to the corresponding homogeneous systems as catalyst/catalyst interactions and bimolecular decomposition reactions are inhibited. Additionally, using a "two-pot" device, the supported Ir catalysts and metathesis catalysts can be physically separated and run at different temperatures. This system with isolated catalysts shows very high turnover numbers and is selective for the formation of high molecular weight alkanes.

Substituted pyridines were employed to prepare a series of terphenylcarboxylate-bridged diiron(II) compounds to mimic aspects of the chemistry at the active sites of bacterial multicomponent monooxygenases, including soluble methane monooxygenase (sMMO) and toluene monooxygenase (ToMO). Complexes of general formula [Fe2(O2CArTol)4L], L = 2, 3, or 4-pyridyldiphenylphosphine, 2-pyridylphenylsulfide, or 2-benzylpyridine and ArTol = 2,6-di(p-tolyl)benzoate, were synthesized and characterized by X-ray crystallography. Upon exposure of these compounds to dioxygen, ligand oxidation ensued and, in one case, proceeded catalytically.

Progress toward the development of functional models of the carboxylate-bridged diiron active site in soluble methane monooxygenase is described in which potential substrates are introduced as substituents on bound pyridine ligands. Thiol, sulfide, sulfoxide, and phosphine moieties incorporated into a pyridine ligand were allowed to react with the preassembled diiron(II) complex [Fe 2 (μ-O 2 CAr R ) 2 (O 2 CAr R ) 2 (THF) 2 ], where

In this study benzyl and ethyl groups were appended to pyridine and aniline ancillary ligands in diiron (II) complexes of the type [Fe 2 (μ-O 2 CAr R ) 2 (O 2 CAr R ) 2 (L) 2 ], where

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