SnBrMe3 and dichalcogenides (ER)(2) as oxidants: Synthesis of platinum(IV) complexes, and C···C and C···E coupling from pallada(IV)cyclopentane complexes and PdMe2(EPh){(pz)(3)BH} {E = O2C, S, Se; [(pz)(3)BH](-) tris(pyrazol-1-yl)borate}

Oxidation of the platinum(II) species [PtMe 2{(pz) 3BH}] - {[(pz) 3BH] -=tris(pyrazol-1-yl)borate} by SnBrMe 3 and the Group 16 oxidants (ER) 2 results in the formation of a series of stable platinum(IV) complexes PtMe 2(SnMe 3){(pz) 3BH} and PtMe 2(ER){(pz) 3BH} (ER=O 2CPh, SMe, SPh, SeMe, SePh). In contrast, the palladium(II) analogue does not react with SnBrMe 3 and reacts with (O 2CPh) 2 to form a 1:1 ratio of PdMe 3{(pz) 3BH} and a Pd IIMe species. The oxidants (EPh) 2 (E=S, Se) react with [PdMe 2{(pz) 3BH}] - to form unstable but NMR detectable species analogous to the platinum(IV) complexes followed by reductive elimination via C⋯C, C⋯S and C⋯Se bond formation processes. The pallada(II)cyclopentane species [Pd(CH 2CH 2CH 2CH 2){(pz) 3BH }] - reacts with (ER) 2 to form unstable species Pd(CH 2CH 2CH 2CH 2)(ER){(pz) 3BH} (ER=O 2CPh, SPh, SePh) followed by related decomposition reactions.