Preparation and crystal and molecular structures of uranyl complexes of 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione and the pyrazol-3-one analogue

Abstract

Uranyl complexes of the ligands 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (Hbmppt), the 3-one analogue (Hbmpp), and the corresponding anions were prepared and characterized by elemental analysis and spectroscopic methods. The complexes UO 2(NO 3) 2(Hbmppt)· acetone and UO 2(NO 3) 2(Hbmpp)·acetone can be isolated from the reaction of UO 2(NO 3) 2·6H 2O and Hbmppt for Hbmpp in acetone. In ethanol, UO 2(NO 3) 2·6H 2O reacts with K(bmppt) or Hbmpp to give UO 2(bmppt) 2·2EtOH or UO 2(bmpp) 2· 2EtOH, respectively. The ethanol adducts will react with dimethylsulfoxide to yield the dmso complexes UO 2(bmppt) 2(dmso)·acetone and UO 2(bmpp) 2(dmso). UO 2(NO 3) 2(Hbmmppt)·acetone crystallizes in the triclinic space group P l with a = 9.663(5), b = 11.522(4), c = 11.823(3) Å, α = 78.18(3), β = 72.56(3), γ = 76.54(4)°, Z = 2, V = 1208.3 Å 3, p calc = 2.05 g cm −3, R F = 0.031, R wF = 0.038. The crystal structure shows two bidentate nitrate anions and a neutral bidentate Hbmppt ligand (US = 2.871(3) Å) in the equational plane of the UO 2 2+ ion. The Hbmppt ligand is bound as the NH tautomer with a hydrogen bond between the NH group and the oxygen atom of the acetone of crystallization (N⋯O = 2.71 Å). UO 2(bmppt) 2(dmso)· acetone crystallizes in the monoclinic space group P2 1/ n with a = 16.010(2), b = 11.050(2), c = 23.084(4), β = 98.77(2)°, Z = 4, V = 4035.7, p calc = 1.63 g cm −3, R F = 0.052, R wF = 0.090. The crystal structure shows discrete molecules of UO 2(bmppt) 2(dmso) with a pentagonal bipyramidal geometry. The UO 2 2+ group is coordinated with two bidentate bmppt anions and the oxygen of a dmso molecule in the equatorial plane. The bmppt anions are bound quite unsymmetrically. The dihedral angle between the plane of one bmppt anion (US = 2.836(6), UO = 2.36(1) Å) and the uranyl equatorial plane is 38.5° while for the other bmppt anion (US = 2.902(6), UO = 2.29(1) Å) the dihedral angle is only 11°.