Platinum bis(phosphine) complexes of 1,8-naphthosultam

• Platinum phosphine complexes with naphthosulfam anion ligands have been prepared.
• The naphthosulfam coordinates through its nitrogen atom.
• The complexes were characterized by NMR and MS.
• Molecular structures were determined by X-ray crystallography.

A series of bis(phosphine) platinum complexes 1–4 and 6–8 that bear the 1,8-naphthosultam ligand (L) have been synthesised. The nitrogen atom in L was deprotonated with sodium tert-butoxide to form the sodium salt. Metathetical reaction of the sodium salt (1 eq.) with the appropriate cis-dichlorobis(phosphine)platinum (1 eq.) in THF resulted in the formation of platinum complexes [Pt(PR3)2(L)Cl] (R3 = Ph3; 1, Ph2Me; 2, PhMe2; 3, Me3; 4), whilst reaction with [Pt(COD)Cl2] afforded [Pt(COD)(L)Cl] (5). The corresponding reaction employing two equivalents of L, two equivalents of NaOtBu and one equivalent of [Pt(PR3)2Cl2]/[Pt(COD)Cl2] yielded complexes [Pt(PR3)2(L)2] (R3 = Ph2Me; 6, PhMe2; 7, Me3; 8) and [Pt(COD)(L)2] (9). L, 1, 5 and 9 have been fully characterised, principally by multinuclear magnetic resonance and IR spectroscopy and mass spectrometry, the remaining members of the series were analysed by 31P NMR only. Unsymmetrical complexes 1–4 provide examples of AX spin systems, with appropriate satellites attributed to 31P NMR-195Pt coupling. X-ray structures determined for 1,8-naphthosultam L, and complexes 1, 5 and 9 and where appropriate the platinum metal geometry, N-S distance and ligand distortions were compared.

The first examples of complexes containing the 1,8-naphthosultam anion are described.Figure optionsDownload as PowerPoint slide