A comparative study of the synthesis, stereochemical characterization and reactivity of new chiral ruthenium(II) complexes with (aminoferrocenyl)phosphine ligands. X-ray crystal structure of RuClH(cod)(PTFA) and Ru(eta(3)-C8H13)Cl(PPFA) [PTFA=1-diphenylphosphino-2,3-endo-(alpha-dimethylamino)tetramethyleneferrocene and PPFA=2-(1-dimethylaminoethyl)-1-diphenylphosphinoferrocene]

The (aminoferrocenyl)phosphine ligands 2-(1-dimethylaminoethyl)-1-diphenylp hosphinoferrocene (PPFA), 1-diphenylphosphino-2,1'-(1-dimethylaminopropaned iyl)ferrocene (PAPF), and 1-diphenylphosphino-2,3-endo- (alpha-dimethylamin o)tetramethyleneferrocene (PTFA) were used to synthesise new ruthenium(II) complexes. Reaction of RuClH(bpzm)(cod) [bpzm=bis(pyrazol-1-yl)methane, cod =1,5-cyclooctadiene] with PTFA, PAPF or PPFA gave rise to the new hydride c omplexes: RuClH(cod)(NP), NP=PTFA, 1; PAPF, 2; PPFA, 3. Complex 2 exists as two isomers with mutually trans hydride and chloride ligands that are orie nted differently with respect to the aminophosphine ligand. It was not poss ible to isolate 3 in its pure form because it evolves in solution to Ru(eta (3)-C8H13)Cl(PPFA) 4 as the final product. Reaction of RuCl2(PPh3)(3) with the (aminoferrocenyl)phosphine ligands gave RuCl2(PPh3)(PTFA) 5 and the kno wn complex RuCl2(PPh3)(PPFA). The reaction with PAPF led to a complex mixtu re. Complex 5 did not react with H-2 (5 atm) or superhydride but reaction w ith KBH4 in EtOH gave rise to one or two isomers of the hydride RuH(eta(2)- BH4)(PPh3)(PTFA) 6. The fluxional behaviour of the BH4 group was studied an d, for the major isomer, two different energy barriers were found for the h ydride scrambling process. A two-step mechanism is proposed. The molecular structures of 1 and 4 were determined by X-ray diffraction.