The first bidentate phosphanylborohydride: Synthesis, structure, and reactivity towards [CpFe(CO)2I]

Deprotonation of the phosphane-borane adduct rac/meso-(HP(BH3)(Ph)CH2)2 (2) with KH provides facile access to the bidentate phosphanylborohydride rac/meso-K2[(P(BH3)(Ph)CH2)2] (3). Treatment of 3 with two equivalents of [CpFe(CO)2I] gives the dinuclear complex rac/meso-[(CpFe(CO)2)2-μ-(P(BH3)(Ph)CH2)2] (4). Single crystals of the pure diastereomers meso-2, meso-3(thf)4, and rac-4 have been grown from toluene/pentane, diethyl ether/thf, and benzene/pentane, respectively. The molecular structures of all three compounds have been determined by X-ray crystallography.