Platinum hydrogen bonding interactions

Models of adducts that link one strand of DNA to the other (interstrand) have also been produced121 2121. These, too, reveal hydrogen bonding interactions consistent with established structure-activity relationships. The models have been used to aid in the design of new platinum(II) complexes that should form the interstrand adducts in preference to intrastrand adducts12151. 

The employment of diphenylphosphinopropanoic acid as a building block in the supramolecular assembly of a cyclometalated platinum(II) polymer 49 directed by -stacking and hydrogen-bonding interactions has been described [ 16g]. 

Nickel and platinum complexes of alkynols and alkynediols are an interesting class of organometallic complex self-associated by O-H- -O hydrogen-bond interactions. Their solid-state supramolecular assembly has been the subject of thorough studies [127]. 

The paper fiirther revealed that the reduetion on Fe(II) of OH, formed from water oxidation, had a reversible potential of 0.64 V for Fe(II) (Equation 5.38), which was about the same as that calculated for 1-fold bond Pt (0.61 V at the B3LYP level). The paper suggested that the Fe-OH formation contributed to the observed overpotential on iron maerocycles in the same way that it did for the platinum eleetrode. In eomparison with Pt, the paper concluded, the important difference was the hydrogen bond interaction between (OHOH) bonded to Fe(II) and a nitrogen lone-pair orbital in the N4 chelate. This interaction prevented hydrogen peroxide from leaving as a two-electron reduction product and provided a path for reduction to water. 

A mechanism that involves a zwitterionic intermediate 25 that is featured by hydrogen bonding interaction between its P(0)R2 moiety and a Brpnsted acid (X-OH) is proposed (Scheme 36). Formation of such a complex has not been substantiated with palladium due to the difficulty of isolation of species 24. However, platinum analogues HPt[P(0)R2](dmpe) have been found to react... 

Hydrogen bonding between an SiOH group and fluorine occurs in the platinum complex 44 [prepared by hydrolysis of a bis(alkylidene)-silacyclopropane] in which the SbF6 anion hydrogen bonds to the platinum-containing cation (O - F distance 2.77(2) A) (249). The platinum complex 45 is not reported (250) to form hydrogen bonds, and a more recent study (210) has confirmed that there do not appear to be any OH OH or OH tt interactions. 

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