The liquid hydrogen chloride solvent system. Part XIV. Reactions of π-cyclopentadienyldicarbonyliron dimer, of π-cyclopentadienylirondicarbonyl chloride, bromide, and iodide, and of π-cyclopentadienyltricarbonyliron chloride in the solvent
Abstract
π-Cyclopentadienyldicarbonyliron dimer is monobasic in liquid hydrogen chloride, giving the [(π-C5H5)Fe-(CO)2]2H+ ion. Spectroscopic evidence (Mössbauer, 1H n.m.r., and i.r.) shows that this ion contains two (π-C5H5)-Fe(CO)2 units linked by a symmetric Fe–H–Fe bridge. Reaction of a solution of the dimer with nitrosyl chloride or chlorine gives mixtures containing π-cyclopentadienyldicarbonyliron chloride. π-Cyclopentadienyldicarbonyliron chloride is a base in the solvent forming [(π-C5H5)Fe(CO)2]2Cl+BCl4– on treatment with boron trichloride. π-Cyclopentadienyltricarbonyliron chloride also acts as a base in the solvent giving (π-C5H5)Fe(CO)3+BCl4–with boron trichloride.