99829-02-4Relevant academic research and scientific papers
Synthesis, characterization, and X-ray structural determinations of technetium(V)-oxo-tetradentate amine oxime complexes
Jurisson,Schlemper,Troutner,Canning,Nowotnik,Neirinckx
, p. 543 - 549 (2008/10/08)
A number of neutral and lipophilic oxo(L)technetium(V) complexes have been synthesized, where L is a tetradentate amine oxime for which 3,3,9,9-tetramethyl-4,8-diazaundecane-2,10-dione dioxime (Pn(AO)2) is the prototype. These TcOL complexes have been characterized by their visible-UV spectra, IR spectra, 1H and 13C NMR spectra, fast atom bombardment (FAB) mass spectra, and X-ray diffraction studies. The X-ray crystal structures of four of these complexes show them to be mono(oxo)technetium(V) species with the oxo group situated at the apex of a square pyramid and the technetium lying an average of 0.68 ? above the plane defined by the four nitrogen atoms of the tetradentate amine oxime. In each case the tetradentate amine oxime ligand loses three protons on coordination to the technetium(V) center, resulting in an overall charge of zero for the complex, multiple bonding between the amide nitrogens and the technetium, and intramolecular hydrogen bonding between the oxime oxygens. meso-TcOPn(AO-CH3)2, TcO3N4C11H21, crystallizes in the orthorhombic system, space group P212121, a = 8.607 (2) ?, b = 10.327 (2) ?, c = 16.345 (3) ?, and Z = 4; dl-TcO[(CH3)2Pn(AO-CH3)2], TcO3N4C13H25, crystallizes in the orthorhombic system, space group P212121, a = 6.948 (2) ?, b = 12.460 (3) ?, c = 19.299 (4) ?, and Z = 4; meso-TcO[(CH3)2Pn(AO-CH3)2], TcO3N4C13H25, crystallizes in the monoclinic system, space group P21/n, a = 11.231 (3) ?, b = 24.238 (7) ?, c = 12.645 (7) ?, β = 93.90 (3)°, and Z = 8; TcOPn(AO)(AO-CH3), TcO3N4C12H23, crystallizes in the monoclinic system, space group P21/n, a = 13.048 (3) ?, b = 10.328 (2) ?, c = 12.984 (2) ?, β = 116.68 (2)°, and Z = 4.
