COMPLEX-FORMATION AND LIGAND SUBSTITUTION-REACTIONS OF (2-PICOLYLAMINE)PALLADIUM(II) WITH VARIOUS BIOLOGICALLY RELEVANT LIGANDS - CHARACTERIZATION OF LAMINE)(1,1-CYCLOBUTANEDICARBOXYLATO)PALLADIUM(II)

The influence of a 2-picolylamine (pie) ligand on the reactivity of Pd (TI) complexes was investigated by detailed equilibrium and kinetic st udies. Reactions of [Pd(pic)(H2O)(2)](2+) with chloride, 1,1 -cyclobut anedicarboxylic acid (CBDCAH(2)), inosine (ino), and inosine 5'-monoph osphate (5'-IMP) were studied. A significantly higher reactivity for t he first reaction step involving the displacement of one coordinated s olvent molecule on [Pd(pic)(H2O)(2)](2+) was observed for the nucleosi de inosine (k(10 degrees C) = 25 400 +/- 200 M(-1) s(-1)) than for the nucleotide 5'-IMP (k(10 degrees C) = 7100 +/- 300 M(-1) s(-1)) and fo r CBDCAH(-) (k(25 degrees C) = 5380 +/- 70 M(-1) S-1; Delta H double d agger = 54 +/- 2 kJ mol(-1); Delta S double dagger = 10 +/- 4 J K-1 mo l(-1); Delta V double dagger = -0.2 +/- 0.7 cm(3) mol(-1)). The result s are compared and discussed in reference to data reported for closely related systems in the literature. The molecular structure of [Pd(pic )(CBDCA)1 in solution and in the solid state was resolved. [Pd(pic)(CB DCA)]. 2H(2)O crystallizes in the space group P2(1)/c (monoclinic,a = 5.659(5) Angstrom, b = 18.320(5) Angstrom, c = 14.027(5) Angstrom, bet a = 97.748(5)degrees, V = 1440.94(14) Angstrom(3), Z = 4).