Polyhydride complexes of rhenium with the chelating ligand 1,2-bis(diphenylphosphinite)ethane

✍ Scribed by Sandra Bolaño; Jorge Bravo*; Soledad Garcı́a-Fontán*

• Book ID: 104138430
• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 145 KB
• Volume: 315
• Category: Article
• ISSN: 0020-1693
• DOI: 10.1016/s0020-1693(01)00319-x

✦ Synopsis

The reaction of [ReOCl 3 (AsPh 3 ) 2 ] with Ph 2 POCH 2 CH 2 OPPh 2 (L) in refluxing THF yielded the complex [ReOCl 3 L] (1). The new polyhydride [ReH 7 L] (2) was obtained by treating 1 with NaBH 4 in absolute ethanol. The heptahydride 2 is stable in the solid state but in solution dimerises, giving [Re 2 H 8 L 2 ] (3). Polyhydrides 2 and 3 were characterised as classical species by variable-temperature NMR spectroscopy ( 1 H and 31 P) and T 1 measurements. The protonation of [ReH 7 L] and [Re 2 H 8 L 2 ] in CH 2 Cl 2 -d 2 with HBF 4 •Et 2 O gave the hydride cations [ReH 6 (h-H 2 )L] + and [Re 2 H 9 L 2 ] + , which were characterised as non-classical and classical, respectively, on the basis of T 1(min) measurements. The reaction of 1 with PPh n (OR) 3 -n (L%; n=1, 2; R=Me, Et) in refluxing THF gave [ReCl 3 LL%] (4) in excellent yield. The complex [ReCl 3 L{PPh(OEt) 2 }] was converted to the pentahydride [ReH 5 L{PPh(OEt) 2 }] by treatment with NaBH 4 at room temperature.