A Family of Platinaoxetanes

Abstract

Treatment of the platinaoxetane [Pt2(COD)2(OC7H10)Cl]BF4 (1), prepared from oxo complex [Pt4(COD)4(O)2(Cl)2](BF4)2 and norbornene, with Cl− yields platinaoxetane Pt(COD)(OC7H10) (2) and (COD)PtCl2. Addition of BF3·Et2O to 2 gives the BF3 adduct Pt(COD)(C7H10OBF3) (3). Treatment of 1 with BF3·Et2O also affords 3 along with [Pt(COD)(µ-Cl)]2(BF4)2. COD displacement from 1 by PEt3 gives Pt(PEt3)2(OC7H10) (5) and [Pt(PEt3)3(Cl)]BF4. Complex 5 is also available from 2 and PEt3. Treatment of 5 with BF3 gives Pt(PEt3)2(C7H10OBF3) (6). COD displacement from 3 by PPh3, bis(diphenylphosphino)ethane (dppe), 4,4′-dimethyl-2,2′-bipyridine (Me2bpy), or 4,4′-di-tert-buty-l-2,2′-bipyridine (But2bpy) yields Pt(PPh3)2(C7H10OBF3) (7), Pt(dppe)(C7H10OBF3) (8), Pt(Me2bpy)(C7H10OBF3) (9), and Pt(But2bpy)(C7H10OBF3) (10), respectively. All new complexes have been fully characterized by 1H, 13C, DEPT, 1H−1H COSY, 1H−13C COSY (HMQC), and 195Pt NMR spectroscopy and elemental analysis. Three complexes (3, 6, 10) were characterized by single-crystal X-ray crystallography.