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Synthesis and X-Ray Diffraction Studies of Bis(4-propanoyl-2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-onato) Dioxomolybdenum(VI) and [4-(1-trichloro-2-ethoxy)propanoyl-2,4-dihydro5-methyl-2-phenyl-3 H-pyrazol-3-onato][4-trichloroacetyl-2,4-dihydro5-methyl-2-phenyl-3 H-pyrazol-3-onato] Dioxomolybdenum(VI)

2001; Wiley; Volume: 627; Issue: 1 Linguagem: Inglês

10.1002/1521-3749(200101)627

1521-3749

B. A. Uzoukwu, Karsten Gloe, О. Rademacher,

Vanadium and Halogenation Chemistry

Two 4-acyl-2,4-dihydro-5-methyl-2-phenyl-3 Hpyrazol-3-one complexes of molybdenum(VI), namely (4-propanoyl-2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-onato) dioxomolybdenum(VI), [MoO2(C26H26N4O4)], 1, and (4(1-trichloro-2-ethoxy)-propanoyl)-2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-onato)(4-trichloroacetyl-2,4-dihydro-5methyl-2-phenyl-3 H-pyrazol-3-onato) dioxomolybdenum(VI), [MoO2(C26H21Cl6N4O5)], 2, have been synthesised from a reaction between MoO ion and 4-propanoyl and 4-trichloroacetyl derivatives of 2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-one respectively. The complexes crystallized from solution with stereochemistry that have remarkable deviations from each other and modest deviation from octahedral geometry. X-ray diffraction studies revealed that in 2 an ethoxy moiety was introduced to one of the two ligand anions rather than on the molybdenum atom due to a deprotonation reaction between the complex and ethanol solvent. This unusual reaction in 2 lead to the destruction of the MoVI atom as a pseudo two-fold centre of inversion of the ligands, the non planarity of both the pyrazole rings and chelate rings of the ligand anions as is observed in 1. The yellow complex 1 crystallized in the orthorhombic space group Iba2 with unit cell parameters, a = 9.6757(6) Å, b = 19.854(3) Å, c = 13.464(3) Å; Z = 4 and Dx = 1.516 g cm–3. The yellow complex 2 crystallized in the triclinic space group P1 with unit cell parameters, a = 8.706(8) Å, b = 12.3155(15) Å, c = 16.179(2) Å; α = 107.268(10)°, β = 95.060(9)°, γ = 104.822(8)°; Z = 2 and Dx = 1.709 g cm–3. The UV, IR and 1H NMR spectral data of the complexes were reported. Synthese und röntgenstrukturanalytische Untersuchungen von Bis(4-propanoyl-2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-onato)dioxomolybdän(VI) und [4-(1-trichloro-2-ethoxy)propanoyl-2,4-dihydro5-methyl-2-phenyl-3 H-pyrazol-3-onato](4-trichloroacetyl-2,4-dihydro5-methyl-2-phenyl-3 H-pyrazol-3-onato)dioxomolybdän(VI) Zwei oktaedrische 4-Acyl-2,4-dihydro-5-methyl-2-phenyl-3 H-pyrazol-3-on-Komplexe mit cisDioxomolybdän(VI) wurden durch Reaktion von MoO22+ mit den entsprechenden Liganden in Ethanol/H2O synthetisiert und charakterisiert. Während für 1 die erwartete Bildung eines 1 : 2-Chelatkomplexes (Metall : Ligand) resultiert, kommt es im Falle von 2 bei der Bildung des 1 : 2-Chelatkomplexes zur überraschenden Einführung einer Ethoxyeinheit in Nachbarschaft zur Trichloracetylfunktion eines Pyrazolonliganden. Diese ungewöhnliche Reaktion führt in 2 zum Verlust des Mo(VI)-Inversionszentrums und zu signifikanten Änderungen in der Anordnung der beiden Liganden im Vergleich zu 1. Der gelbe Komplex 1 kristallisiert in der orthorhombischen Raumgruppe Iba2 mit den Zellparametern a = 9.6757(6) Å, b = 19.854(3) Å, c = 13.464(3) Å; Z = 4 und Dx = 1.516 g · cm–3. Der ebenfalls gelbe Komplex 2 weist im Kristall die trikline Raumgruppe P1 mit den Zellparametern a = 8.706(8) Å, b = 12.3155(15) Å, c = 16.179(2) Å; α = 107.268(10)°, β = 95.060(9)°, γ = 104.822(8)°; Z = 2 und Dx = 1.709 g · cm–3 auf. UV-, IR- und 1H-NMR-Spektren werden diskutiert.