Inosine palladium complexes

OjNjQHis, Cytidine palladium(II) complexes, 23 54 OSN4C10H12, Inosine palladium(II) complexes, 23 51-54 OsH CioHi3, Guanosine palladium(II) complexes, 23 51-54 OsUCioHij, Uranium(V), pentaethoxy-, 21 165... 

N403PtTI4C Platinate(ll), tetracyano-, thallium carbonate (1 4 1), 21 153, 154 N404ThCMH42, Thorium, bis(2,4-pentanedio-nato)(5,10,15,20-tetraphenyIporphyri-nato(2 —)]-, 22 160 N405CioHi2. Inosine, palladium(II) complexes, 23 51-54 N4O4CI0Hi2, Xanthosine, palladium(Il) complexes, 23 54 N4PtC44H34, Praseodymium, [5,10,15,20-tet-rakis(4-methylphenyl)porphyrinato-(2-)]-, 22 160... 

Similar kinetic rate laws have recently been found for the reaction between [PdCl(dien)]+ and inosine, i, k-i, and ks all being of similar magnitude (32). With adenosine instead of Ino, A3 is diminished to the extent that Ai and A 1 can be treated as a pre-equilibrium, and with the unreactive nucleobase uridine, even the reverse anation step, A 3, can again make a contribution. This type of complication has been found in reactions of palladium-dien complexes with the common buffering agent tris(hydroxymethyl)aminomethane (33), which acts as a poor nucleophile. 

Two mmoles of the corresponding cis-[dichlorobis(nucleoside)palladium(II)] (1.4274 g for the inosine and 1.4882 g for the guanosine complex) are placed in a 100-mL beaker containing a magnetic stirring bar. Upon addition of about 50 mL of distilled water (with stirring) the initial complex dissolves, and, almost instantaneously (after 10-15 min for inosine), a new, yellow precipitate is formed. The pH of this water suspension becomes acidic, due to the liberation of HC1. The stirring is continued for about two hours to attain completion of the reaction, while the pH is kept between 6.0 and 6.5 by the dropwise addition of a solution of 0.1 N KOH. The final pH value of the suspension should be 6.0-6.5. 

SnMe2Cl2(adenine)2 and SnPhCl2(0H)(Adenine)2 thought to involve N-7 of the bases.Treatment of Inosine and guanosine with palladium chloride in acid gave a set of complexes... 

Substitution. The kinetics of reactions of /ra/t -CPdClgCR SR ) ] complexes with a series of amines of various basicities and steric requirements have been studied in 1,2-dimethoxyethane at 298 K. In fact the first step is fast, and it is the second step whose kinetics have been examined here. Amine basicity is an important factor logarithms of second-order rate constants correlate linearly with amine pKa values in the absence of steric hindrance. Steric factors have a large effect when the incoming amine e.g. 2-methylpyridine) or the leaving sulphide (e.g. phenyl isopropyl sulphide) is bulky. The kinetic pattern for the reaction of [PdCl2(cod)] with 2,2 -bipyridyl in aqueous methanol has been interpreted by the reaction sequence shown in Scheme 3. The mechanism is dissociative with respect to the palladium centre. The rate law for the reaction of the [PdBr(dien)]+ cation with inosine has already been discussed in the introductory section to this chapter. 

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