Preparation and characterisation of [Pt(SeSN2)(PR3)2], [Pt(Se2N2)(PR3)2], [Pt(SeSN2H)(PR3)2]BF4, and [Pt(Se2N2H)(PR3)2]BF4
Abstract
Reaction of [Se2N2S]2Cl2, or SeCl4–[S4N3]Cl, with [PtCl2(PR3)2](PR3= PEt3, PMe2Ph, PMePh2, PPh3, or ½ Ph2PCH2CH2PPh2) in liquid ammonia gives complexes of the type [Pt(SeSN2)(PR3)2](ca. 70% yield). Reaction of SeCl4 with [PtCl2(PR3)2](PR3= PEt3, PMe2Ph, PMePh2, PPh3, or ½ Ph2PCH2CH2PPh2) in liquid ammonia produces [Pt(Se2N2)(PR3)2] in variable yield (ca. 24–74%). Treatment of [Pt(SeSN2)(PR3)2] or [Pt(Se2N2)(PR3)2] with HBF4in tetrahydrofuran–benzene produces [Pt(SeSN2H)(PR3)2] BF4 or [Pt(Se2N2H)(PR3)2] BF4 quantitatively according to 31P n.m.r. spectroscopy (ca. 75% isolated). The identity of the complexes was established by 31P n.m.r., i.r., mass spectra, and microanalyses. Proton-exchange reactions reveal increasing basicity in the series [Pt(S2N2)(PR3)2]≈[Pt(SeSN2)(PR3)2], [Pd(S2N2)(PR3)2], [Pt(Se2N2)(PR3)2].