Reactions of pentaphenyland penta(para-tolyl)antimony with ferrocene dicarboxylic acid

In reactions of pentaphenyl- and penta( para -tolyl)antimony with ferrocene dicarboxylic acid (molar ratios 1:1 and 2:1) in toluene (20 °С, 24 h), hydrogen in one or two carboxylate groups is replaced with formation of tetraarylantimony ferrocene carboxylates HOOС5H4FeС5H4C(O)OSbPh4 (1), HOOС5H4FeС5H4C(O)OSbTol4 (2), Ph4SbC(O)OC5H4FeС5H4C(O)OSbPh4 (3) and p -Tol4SbC(O)OC5H4FeС5H4C(O)OSbTol4 (4), yielding up to 83 %. Compounds 1-4 have been identified by elemental analysis, IR spectroscopy, and X-ray diffraction analysis for 4. X-ray diffraction analysis of complex 4 has been performed on a D8 Quest Bruker automatic four-circle diffractometer (Mo Kα radiation, λ = 0.71073 Å, graphite monochromator ) at 293 K. Crystallographic characteristics of compound 4: monoclinic system, space group P21/ c , a = 17.227(17), b = 11.064(9), c = 30.59(3) Å, β = 100.00(4) deg., V = 5742(9) Å3, Z = 4, rcalc = 1.440 g/cm3, 2 q 6.02-49.08 deg., total reflections 124343, independent reflections 9436, number of refined parameters 684, R int = 0.1051, GOOF 1.094, R 1 = 0.0536, wR 2 = 0.1309, residual electron density (max/min) 0.88/-1.21 e/Å3. According to the X-ray diffraction analysis data, in crystal 4 coordination of the antimony atoms is distorted octahedral due to the fact that the carboxylate ligand is a bidentate chelating ligand. The diagonal angles in the two octahedra are 146.4(2), 154.0(3), 171.0(2)° and 147.4(2), 154.8(2), 166.9(2)°. The Sb-O distances are 2.296(5), 2.502(5) Å and 2.289(5), 2.453(5) Å, the Sb-C bonds are significantly different (2.146(7)-2.166(7) and 2.123(6)-2.165(7) Å). The structural organization of the crystal is mainly due to the interactions of the С-Н··· p -type.