823786-34-1Relevant articles and documents
Synthesis and characterization of the first examples of dicationic dihydrogen complexes of iron and ruthenium with the PF3 ligand
Nanishankar,Nethaji, Munirathinam,Jagirdar, Balaji R.
, p. 3048 - 3056 (2007/10/03)
New dicationic dihydrogen complexes of the type trans-[M(η2- H2)(PF3)(diphosphane)2]2+ [M = Ru, diphosphane = dppm (Ph2PCH2PPh2); M = Fe, Ru, diphosphane = dppe (Ph2PCH2CH2PPh2)] have been prepared from the precursor hydrides trans-[M(H)(PF 3)(diphosphane)2]+ upon reaction with HOTf. In the case of dppm, in addition to the trans-dihydrogen complex cis-[Ru(η2-H2)(PF3)(dppm)2] 2+ was also obtained in the protonation reaction. The intact nature of the H-H bond in these derivatives has been established using the spin-lattice relaxation time measurements (short T1 values) and the large J H,D coupling constant of the H-D isotopomers. The H-H bond lengths and the stabilities of the dihydrogen complexes are discussed in terms of the π-acidity of the PF3 ligand and compared with other systems possessing trans CO and CNH ligands. The trans-[Ru(η2-H 2)(PF3)(dppe)2]2+ complex was found to be remarkably stable with respect to the loss of bound H2 for a period of about 16 h. The H-D isotopomer of this complex exhibits small temperature variations in the JH,D coupling constant. The X-ray crystal structure of trans-[Ru(H)(PF3)(dppm)2][BF 4] has been determined. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
