The reaction of Ph2PH with Pt(PEt3)3 in 2:1 molar ratio produces the linear triplatinum complex [Pt3H2(μ-PPh2)4 (PEt3)2] (1). X-ray crystallography of 1 shows the structure of the complex with two PEt3 ligands at anti positions, while it exists as a mixture of the isomers with PEt3at anti and syn positions. Pt(PEt3)3 reacts with equimolar Ph2PH to afford the dinuclear complex [Pt2H2(μ-PPh2)2 (PEt3)2] (2) and the cyclic trinuclear complex [Pt3H(μ-PPh2)3(PEt3)3] (3) depending on the reaction conditions. A dinuclear platinum(II) complex with a structure similar to 2, [Pt2H2(μ-PtBu2)2 (PEt3)2] (4) , is obtained by the reaction of tBu2PH with Pt(PEt3)3. Isolated complexes 2 and 3 cleanly react with Ph2PH to form 1, indicating that the reaction of Ph2PH with Pt(PEt3)3, giving 1, involves these complexes as the intermediates. Complex 3 contains a triangular Pt3 core with Pt-Pt bonds in the range 2.9784(4) - 2.9983(3) Å, as shown by X-ray crystallography. The 1H NMR spectrum of 3 exhibits the hydrido signal at δ -7.98 accompanied by splitting due to H - P and H - Pt coupling. Complex 3 reacts with Ph3SiH and Ph2SiH2 to give silylplatinum complexes [Pt3(SiHn+1Ph4-n) (μ-PPh2)3(PEt3)2] (5, n = 1; 6, n = 2). Cationic triangular complexes [Pt3 (μ-PPh2)3(PEt3)3]+ I- (7) and [Pt3(μ-PPh2)3 (PEt3)3]+ [B4O4 Ar4(OH)]- (8, Ar = C6H4Me-4; 9, Ar = C6H4F-4; 10, Ar = C6H4 CF3-4) are obtained from the reactions of complex 3 with MeI and with ArB(OH)2, respectively.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry