Preparation, structure, and property of organic isothiocyanide–Fe(II) complexes, trans-[FeH(NCSR)(dppe)2][X] (dppe=Ph2PCH2CH2PPh2; R=Me, Et, Pr, i-Pr, CH2CHCH2, CH2CCH; X=I, Br, CF3SO3, BF4)

The compound trans-[FeH(Cl)(dppe)2] (1) reacted with KSCN to give trans-[FeH(NCS)(dppe)2] (2), which underwent electrophilic attack by alkyl iodides or alkyl bromides (RX) to give organic isothiocyanide–Fe(II) complexes of the type trans-[FeH(NCSR)(dppe)2]X {X=I: R=Me (3), Et (4), Pr (5), CH2CHCH2 (6), i-Pr (7); X=Br: R=Pr (8), CH2CHCH2 (9), CH2CCH (10)}. Compound 2 also reacted with strong electrohphiles, MeSO3CF3 and Me3O·BF4, to give trans-[FeH(NCSMe)(dppe)2][SO3CF3] (11) and trans-[FeH(NCSMe)(dppe)2][BF4] (12), respectively. Compounds 2 and 11 were characterized structurally by X-ray diffraction, in which the hydride ligand appears to be involved in the dihydrogen bonding, M–H⋯H–C.