Probing the Lewis basicity of the metalloligand [Pt₂(μ-Se)₂(PPh₃)₄] on tin substrates by electrospray mass spectrometry

Abstract

Electrospray Mass Spectrometry (ESMS) has been used as a tool to probe the reactivity of [Pt₂(μ-Se)₂(PPh₃)₄] with tin(IV) substrates, which leads to the formation of charged coordination complexes via loss of halides. The metal substrates used in the displacement reactions are SnRxCl4 – x (x = 1, R = Me, Bu or Ph; x = 2, R = Me, Bu, Et or Ph; x = 3, R = Me, Ph) and Sn(CH₂Ph)₂Br₂. Most of these reactions gave both mono- and di-cations through displacement of one and two halides respectively by [Pt₂(μ-Se)₂(PPh₃)₄]. ESMS was also used to monitor the progress of reactions. The products, upon isolation, were also characterized by NMR and X-ray single crystal crystallographic analysis. The crystal structures of the aggregates [Pt₂(μ₃-Se)₂(PPh₃)₄(SnBuCl₂)][PF₆], [Pt₂(μ₃-Se)₂(PPh₃)₄(SnBu₂Cl)][PF₆] and [Pt₂(μ₃-Se)₂(PPh₃)₄(SnMe₂Cl)][PF₆] are reported and discussed.