Amidate-bridged platinum complexes

C. Oxidation of Organic Substances Catalyzed by Amidate-Bridged Platinum(III) Complexes... 

II. Syntheses and Structures of Platinum-Blues and Related Amidate-Bridge Platinum"1 Complexes... 

Other metal-centered catalysts that have been studied include (te)strapped chiral porphyrins derived from L-proline, which can induce modest (< 30%) enantioselectivity <02EJIOC1666>. Supported amidate-bridged platinum blue complexes, which have not yet been applied to chiral epoxidation, but which show promise of utilizing molecular oxygen as the terminal oxidant, have... 

With respect to polymer-bound platinum catalysts, a dinuclear amidate-bridged platinum(III) complex was supported on pol3winylpyridine [95] and tested as catalyst in the epoxidation of cyclohexene and styrene by isobutyralde-hyde/O2. Its catalytic activity was found to be significantly lower compared to the same complex immobilized on inorganic supports. 

W. Chen, J. Yamada, K. Matsumoto, Catalytic olefin epoxidation with molecular oxygen over supported amidate-bridged platinum blue complexes, Synth. Commun. 32 (2002) 17. 

The doubly bridged cobalt and, in one case, platinum complexes contain an 0 and an amide or hydroxo bridge.The superoxo... 

The pivalamidate-bridged diplatinum ketonyl complexes may be prepared from the reaction of platinum blue complex and nitric acid in acetone. Two isomers with the amidate configuration in head-to-head and head-to-tail modes and the ketonyl ligand at one axial end are characterized (Scheme 16). An alternative route is from catalyzed oxidation of olefins. ... 

The results cited above indicated the platinum—pyrimidine blues to be oligomeric, mixed-valent cations with metal—metal bonding, in line with opinions on the original platinblau , first described in 1908 from the reaction of platinum salts in the presence of amides [10]. The bridging, and thus chain extension, occurs through the pyrimidines and the remarkable propensity of platinum—ammine complexes to stack in species such as [Pt(NH3)2Br2Pt(NH3)2Br4] [11] undoubtedly contributes to the chain extension and indeed, the platinum—pyrimidine blues are another example of this tendency. 

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