Gas-Phase Studies on the Reactivity of the Azido(diethylenetriamine)platinum(II) Cation and Derived Species

Abstract

The recent report of the gas-phase loss of nitrogen from [Pt(dien)₃]⁺ (dien = diethylenetriamine = N-(2-amino-ethyl)ethane-1,2-diamine) under collision-induced dissociation (CID) conditions has prompted us to investigate the intriguing structure(s)of [Pt(dien)N]⁺. This was carried out via CID and ion–molecule reactions (IMR) of [Pt(dien)N]⁺ in the gas phase. Labelling studies (¹⁵N and ²H labelling of the dien ligand) were also employed. As a result, some of the previously proposed structures were ruled out and three other potential structures of [Pt(dien)N]⁺ are considered. Labelling studies also indicate that the hydrogen atoms of both the amino groups and the carbon backbone of the dien ligand are involved in loss of NH₃ from [Pt(dien)N]⁺. The gas-phase chemistry of [Pt(dien)N-NH₃]⁺, the fragmentation product of [Pt(dien)N]⁺, was also probed using IMR and CID. The crystal structure of the [Pt(dien)₃]⁺ cation has also been determined.