Amidate bridging

The reaction is best carried out at -40°C, otherwise amide bridged species [(NH3)4Pt(NH2)2Pt(NH3)4]Cl6 are obtained. 

It is of incidental interest that a little work has been done on dicobalt systems. Doyle and Sykes have made a study of the reduction of decammine-//-amidodi-cobalt(Ill), (NH3)5Co NH2-Co(NH3)5 , by V(II). Since the rate is independent of hydrogen-ion concentration the mechanism cannot involve an amide bridge and must be outer-sphere, as it is in the case of the reduction of Co(NH3)6 by V(1I) . Both the binuclear complex and Co(NH3)6 are inert to substitution but the former is capable of functioning as a two-equivalent oxidant. Thus the two likely mechanisms are... 

Platinum-Blues and the Related Amidate-Bridged Platinum111 Compounds... 

Structures and Reactivities of Platinum-Blues and the Related Amidate-Bridged Platinum111 Compounds Kazuko Matsumoto and Ken Sakai... 

STRUCTURES AND REACTIVITIES OF PLATINUM-BLUES AND THE RELATED AMIDATE-BRIDGED PLATINUM111 COMPOUNDS... 

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... 

The advantage of these complexes is that each Pt complex is isolated in pure form, and the crystal structure is known. Based on 1H-and 195Pt-NMR spectroscopy, the antitumor active compounds were found to be disrupted as shown in Fig. 20, giving finally [Pt(NH3)2(H20)2]2+, which is the same hydrolysis product as ds-DDP and is responsible for the activity. Therefore, the subsequent reaction with DNA bases and the mechanism would be the same with those of cis-DDP. The antitumor inactive compounds are relatively stable and are disrupted only to dinuclear amidate-bridged compounds. No further decomposition to [Pt(NH3)2(H20)2]2+ occurs. 

A series of enterobactin analogs has been prepared as structural analogs to Fe(III) complexes. These species have facile oxidation processes (Ef = —0.53 to —l.OOV versus Cp2Fe/DMF) and are based on three catecholato ligands joined to a central aromatic ring (Fig. 7) or nitrogen atom by amide bridges [52]. The parent [V(cat)3] (cat = 1,2-catecholato)... 

The great polarizability along the Pt-Pt axis appears to be a characteristic feature of Pt111 dimers which therefore can span the whole range of intermediate character between Pt11 and PtIv. The olefin oxidation catalyzed by amidate-bridged Ptm dinuclear-species is believed to take place through ol-... 

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