关键词: 晶体结构, 皮考林酰肼, 铁配合物

Abstract: Two iron complexes with N-acetylpicoloylhydrazide (Haphz) and N-phenylpicoloylhydrazide(Hphphz), [Fe₂(aphz)₂(μ-CH₃OH)₂Cl₂]·CH₃OH(1, C₁₉H₂₆Cl₂Fe₂N₆O₇, Mr= 633.06) and Fe(phphz)Cl₂(2, C₁₃H₁₀Cl₂FeN₃O₂, Mr=366.99), were synthesized. Complex 1 belongs to a triclinic system, space group P1, with cell parameters a=0.83359(6) nm, b=1.09990(9) nm, c=0.75054(7) nm, α=91.412(3)°, β=96.683(3)°, γ=107.997(6)°, V=0.64869(9)nm³, Z=1, Dc=1.621Mg/m³, F(000)₃₂₄, μ(Mo Kα)=1.374mm^-1, R=0.0318 and _wR=0.0864 for 2547 observed reflections, GOF=1.112. Complex 2 belongs to triclinic system, space group P1, a=0.69038(6) nm, b_0.94607(9) nm, c=1.18582(7) nm, α=89.383(5)°, β=81.515(2)°, γ=69.214(2)°, V=0.7155(1)nm³, Z=2, Dc=1.704 Mg/m³, F(000)=370, μ(Mo Kα)=1.433 mm^-1, R=0.0681 and _wR=0.1352 for 1720 observed reflections, GOF=1.056. The binuclear complex 1 has a crystallographic center. The two methanol oxygen atoms in complex 1 bridges two iron atoms, forming a Fe₂(μ-O)₂core with crystallographic centrosymmetry and Fe...Fe distance is 0.31609 nm. The iron atom is octahedrally coordinated by two nitrogen atoms and one oxygen of the N-acetylpicoloylhydrazide ligand, two methanol oxygen atoms and one chloride ion. The neighboring molecules in complex 1 are connected by hydrogen bonding, forming an infinite chain structure. The iron(Ⅲ) ion in complex 2 has a strongly distorted square pyramidal geometry with three donors of the N-phenylpicoloylhydrazide ligand and two chloride ions. The two centrosymmetry-related molecules of complex 2 are connected as a pair by two N-H...Ohydrogen bonds. In the two title complexes, ν(C=O) and ν(C-N) are shifted to lower frequencies in IRspectra; π-π^*charge transitions and d-π^*charge-transitions are observed in their electronic spectra. The emission lines (λ_ex=310 nm) are shifted to higher frequencies in fluorescence spectra.

Key words: Crystal structure, Picoloylhydrazide, Iron complex