Ligand functionalization, reactivity, and transformation at the selenide centers of [Pt2(μ-Se)2(PPh3)4] with organic halides

Abstract

The selenium centers of [Pt2(μ-Se)2(PPh3)4] are subject to electrophilic attack from various organic halides. Reactions with Mel, n-BuCl, α,α′-dichloro-p-xylene, and α,α′-dichloro-o-xylene give [Pt2(μ-Se)(μ-SeMe)(PPh3)4]+, [Pt2(μ-Se)(μ-SeBu)(PPh3)4]+, [Pt2(μ-Se)(μ-SeCH2C6H4CH2 Cl)(PPh3)4]+, and [Pt2(μ-SeCH2C6H4CH2Se) (PPh3)4]2+, respectively, preserving the dinuclear core and giving rise to new selenium-derivatized ligand complexes. Reaction with oxalyl chloride gives [Pt(η2-Se2C2O2-Se,Se′)(PPh 3)2], leading to the disintegration of the core to a mononuclear complex supported by a new chelating selenium donor ligand. Reactions with malonyl chloride and succinyl chloride give [(COCH2COCl)Se]2 and [(COCH2CH2COCl)Se]2 respectively, leading to complex disintegration and liberation of new selenium materials. The crystal structures of the aggregates [Pt2(μ-Se)(μ-SeMe)(PPh3)4][PF6 ], [Pt2(μ3-Se)2(PPh3)4(CH 2C6H4CH2)][PF6]1.25 [Cl]0.75, and [Pt(η2-Se2C2O2-Se,Se′)(PPh 3)2] are described. The potential of using [Pt2(μ-Se)2(PPh3)4] as a source for metal-assisted synthesis of new and unusual organoselenium compounds is discussed.