SYNTHESIS AND DECOMPOSITION OF NEUTRAL PALLADIUM(IV) COMPLEXES CONTAINING FAC-PDME2R GROUPS, INCLUDING REDUCTIVE ELIMINATION BY ETA-1-PROPENYLPALLADIUM(IV) COMPLEXES TO FORM ETA-3-PROPENYLPALLADIUM(II) SPECIES

Oxidative addition of ethyl iodide to PdMe2(2,2′-bipyridyl) in (CD3)2CO gives the unstable "PdIMe2Et(bpy)", which undergoes reductive elimination to form PdIR(bpy) (R = Me, Et), ethane, and propane. Ethene and palladium metal are also formed, and are attributed to decomposition of PdIEt(bpy) via β-elimination. Similar results are obtained with n-propyl iodide, although a palladium(IV) intermediate was not detected, but CH2CHCH2X (X = Br, I) and PhCHCHCH2Br give isolable complexes fac-PdXMe2(CH2CHCHR)(L2) (R = H, Ph; L2 = bpy, phen). The propenyl complexes decompose at ambient temperature to form ethane, a trace of PdXMe(L2), and mixtures of [Pd(η3-C3H5)(L2)]X and [Pd(η3-C3H5)(L2)]-[Pd (η3-C3H5)X2]; for fac-PdBrMe2(CH2CHCH2)(bpy) the major palladium(II) product is [Pd(η3-C3H5)(bpy)]Br. © 1990.