The reactions of sulfuryl chloride with [Fe2(η-C5H5)2(CO)4-n(CNMe)n] (n = 0, 1, 2 and 4) and related complexes. The crystal structure of [Fe(η5-C9H7)(CO)3] [FeCl4]

Abstract

The reaction of [Fe2(η-C5H5)2(CO)4] with SO2Cl2 at room temperature is instantaneous. It gives a mixture of [Fe(η-C5H5)(CO)2Cl] and [Fe(η-C5H5)(CO)3] [FeCl4]. The product ratio is solvent-dependent with the former product predominating in polar solvents and the latter in non-polar solvents such as benzene. Other [Fe2(η-dienyl)2(CO)4] (dienyl = MeC5H4 or C9H7) react similarly. These reactions in benzene provide simple direct routes to the salts. Similar mixtures of covalent chlorides and salts are obtained with [Fe2(η-C5H5)2(CO)3(CNMe)] which gives [Fe(η-C5H5)(CO)2Cl], [Fe(η-C5H5)(CO)CNMe)Cl] and [Fe(η-C5H5)(CO)2(CNMe)][FeCl4], and with [Fe2(η-C5H5)2(CO)2(CNMe)2] which gives [Fe(η-C5H5)(CO)(CNMe)Cl] and [Fe(η-C5H5)(CO)(CNMe)2][FeCl4]. However [Fe2(η-C5H5)2(CNMe)4], [Fe2(η-C5H5)2(CO)3{P(OPr-i)3}] and [Fe2(η-C5H5)2(μ-CO)2(μ-dppe)] (dppe = Ph2PCH2CH2PPh2) give only ionic products [Fe(η-C5H5)(CNMe)3][FeCl4], [Fe(η-C5H5)(CO)2{P(OPr-i)3}][FeCl4], and [Fe(η-C5H5)(CO)2(η1-dppe)][FeCl4] irrespective of the solvent. The mechanisms of the reactions are discussed on the basis of a previously proposed series of reaction pathways starting from adducts in which the electrophile SO2Cl2 coordinates to the O or N atom of the μ-CO or μ-CNMe ligand of the dimeric substrates. The crystal and molecular structure of [Fe(μ5-C9H7)(CO)3][FeCl4] has been determined by an X-ray diffraction study which confirmed the presence of the tetrahedral [FeCl4]- anion and the pseudo-octahedral cation with its Fe(CO)3 moiety coordinated to the C5 ring of a planar indenyl ligand. The structure was solved by direct methods and refined by least squares procedures to R = 0.0631 for 1406 non-zero unique reflections. The crystal was monoclinic, space group P21/a with a 11.929(3), b 18.612(4), c 7.717(1) Å and β 100.9(1)°, and Z = 4. © 1988.