87392-51-6Relevant academic research and scientific papers
Nucleophilic Substitution at Thionyl- and Sulfuryl Chloride by Metallates. Synthesis and Structure of the SO- and SO2-Complexes 2(CO)2Fe(SOn) (n = 1, 2)
Lorenz, Ingo-Peter,Hiller, Wolfgang,Conrad, Michael
, p. 1383 - 1389 (2007/10/02)
The synthesis of the SO- and SO2-complexes 3 and 4 follows equations (1) and (3) by nucleophilic substitution of SOCl2 or SO2Cl2 by the same metallate 2, 4 can also be obtained by simple air oxidation of solutions of 3 according to equation (2).Spectroscopic investigations indicate a trigonal bipyramidal configuration on iron with both phosphite ligands in axial positions and the sulfur oxide ligands in equatorial positions together with both carbonyl ligands.The X-ray structure analysis of the SO2 complex 4 shows the exactly planar coordination of the sulfur atom and the nearly perpendicular orientation of the SO2 plane to the equator plane; thus complex 4 is isolobal to SO3.The SO ligand in 3 coordinates as a 2c - 2e-system in a bent structure with both atoms lying in the equatorial plane. - Key words: Nucleophilic Substitution at SOCl2 and SO2Cl2, Oxidation of SO Complex, IR Spectra, NMR Spectra, X-Ray
Sulfur dioxide complexes of iron(0): [Fe(L)2(CO)2(SO2)] (L = P(III) ligand). Isomerism and the structures of [Fe(P(OPh)3)2(CO)2(SO2)] and [Fe(P(OC6H4Me-o)3)2(CO) 2(SO2)]
Conway, Paul,Grant, Seamus M.,Manning,Stephens
, p. 3714 - 3721 (2008/10/08)
A series of air-stable [Fe(L)2(CO)2(SO2)] complexes (L = P(III) ligand) have been prepared either from [Fe(L)2(CO)3] by photolysis and subsequent reaction with SO2 when L is a triaryl phosphite or from [Fe(L)2(CO)2(CS2)] by the thermal or photolytic displacement of CS2 by SO2. Their IR spectra are reported and absorption bands due to ν(CO) and ν(SO2) vibrations are assigned. They show that there are two isomeric forms of these complexes, A and B, and the structures of one of each have been determined by X-ray diffraction studies. In both there is trigonal-bipyramidal coordination about Fe with a planar η1(S)-SO2 ligand coordinated equatorially so that the SO2 plane lies ca. perpendicular to the equatorial plane of the complex. However, in [Fe(P(OPh)3)2(CO)2(SO2)] (an isomer A) the two phosphite ligands are axially coordinated, while in [Fe(P(OC6H4Me-o)3)2(CO) 2(SO2)] (an isomer B) they are equatorial. In the solid state all of the complexes adopt the A configuration except when L = (o-ClC6H4O)3P, (o-MeC6H4O)3P, or Ph(o-MeC6H4O)2P. In solution the complexes are found solely as A when L = (p-ClC6H4O)3P, (i-PrO)3P, Ph(i-PrO)2P, Ph(MeO)2P, Ph2(PhO)P, Ph2(MeO)P, Ph2MeP, and Ph3P. When L = (o-ClC6H4O)3P, only B is observed. However there is a solvent-dependent equilibrium mixture of A and B when L = (o-MeC6H4O)3P, Ph(o-MeC6H4O)2P, (m-MeC6H4O)3P, (p-MeC6H4O)3P, (PhO)3P, Ph(PhO)2P, and Ph2(o-MeC6H4O)P with the proportion of B declining along this series in a particular solvent. It is proposed that this equilibrium is largely a consequence of steric effects. A is destabilized by steric interactions between the SO2 ligand and the ortho-H atoms of the axial L ligands, and B is destabilized by L-L interactions. Electronic factors also play their limited part and arise from the nature of the bonding between all three equatorial ligands and Fe. The structures of two of the complexes were solved by the heavy-atom method and refined by least-squares procedures. [Fe(P(OPh)3)2(CO)2(SO2)] crystals (an example of isomer A) were triclinic, space group P1, or P1, with a = 11.027 (5) A?, b = 11.374 (5) A?, c = 15.238 (8) A?, α = 88.3 (1)°, β = 97.7 (1)°, γ = 108.6 (1)°, and Z = 2, and the structure was refined to R = 0.083 for 2437 non-zero unique photographic reflections. [Fe(P(OC6H4Me-o)3)2(CO) 2(SO2)] crystals (an example of isomer B) were monoclinic, space group Cc or C2/c, with a = 19.873 (11) A?, b = 10.725 (5) A?, c = 20.798 (11) A?, β = 100.7 (1)°, and Z = 4, and the structure was refined to R = 0.088 for 1309 non-zero unique photographic reflections.
