Oxidation of Complexes by (O(2)CPh)(2) and (ER)(2) (E = S, Se), Including Structures of Pd(CH(2)CH(2)CH(2)CH(2))(SePh)(2)(bpy) (bpy = 2,2'-Bipyridine) and MMe(2)(SePh)(2)(L(2)) (M = Pd, Pt; L(2) = bpy, 1,10-Phenanthroline) and C.O and C.E Bond Formation at Palladium(IV).
Oxidation of PdMe(2)(L(2)) [L(2) = 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen)] by diphenyl diselenide provides the first examples of stable dimethylpalladium(IV) complexes PdMe(2)(SePh)(2)(L(2)), and pallada(IV)cyclic may be similarly isolated. X-ray structural studies of the octahedral dimethylpalladium(IV) complexes and their isomorphous platinum(IV) analogues have been completed [L(2) = bpy, orthorhombic Pnma; L(2) = phen, triclinic P&onemacr;; an additional phase for PtMe(2)(SePh)(2)(phen), tetragonal, I4(1)/a]. The complexes PdMe(2)(SePh)(2)(L(2)) decompose at moderate temperatures in CDCl(3) following first-order behavior [L(2) = bpy, E(a) approximately 46 kJ mol(-)(1), DeltaS()(20 degrees C) approximately -170 J K(-)(1) mol(-)(1); L(2) = phen, E(a) approximately 36 kJ mol(-)(1), DeltaS()(20 degrees C) approximately -204 J K(-)(1) mol(-)(1)] to give ethane and Se(Ph)Me, together with small quantities of SePh(2). Similar C.C, C.O, C.S, and C.Se bond formation processes occur on decomposition of palladium(IV) species that are too unstable to be isolated on the oxidation of PdMe(2)(bpy) or by (O(2)CPh)(2) or (SPh)(2).
Canty
Allan J.
AJ
Departments of Chemistry, University of Tasmania, Hobart, Tasmania, Australia 7001, and University of Western Australia, Nedlands, Western Australia, Australia 6907.
Jin
Hong
H
Skelton
Brian W.
BW
White
Allan H.
AH