1204887-50-2Relevant academic research and scientific papers
Synthesis, characterization, and structure of a new cobalt(II) Schiff-base complex with quinoxaline- 2-carboxalidine-2-amino-5-methylphenol
Sebastian, Manju,Arun, Vasudevan,Robinson, Ponminiessary P.,Leeju, Pally,Varghese, Digna,Varsha, Gopalakrishnan,Mohammed Yusuff, Karukapadath K.
, p. 307 - 314 (2010)
The mononuclear cobalt(II) complex [CoL2] · H2O (where HL is quinoxaline-2-carboxalidine-2-amino-5-methylphenol) has been prepared and characterized by elemental analysis, conductivity measurement, IR, UV-Vis spectroscopy, TG-DTA, and X-ray structure determination. The crystallographic study shows that cobalt(II) is distorted octahedral with each tridentate NNO Schiff base in a cis arrangement. The crystal exhibits a 2-D polymeric structure parallel to [010] plane, formed by O-H ··· N and O-H ··· O intermolecular hydrogen bonds and π-π stacking interactions, as a racemic mixture of optical enantiomers. The ligand is a Schiff base derived from quinoxaline-2-carboxaldehyde.
Synthesis, structural characterization and catalytic activity study of Mn(II), Fe(III), Ni(II), Cu(II) and Zn(II) complexes of quinoxaline-2- carboxalidine-2-amino-5-methylphenol: Crystal structure of the nickel(II) complex
Sebastian, Manju,Arun,Robinson,Varghese, Annu Anna,Abraham, Rani,Suresh,Yusuff, K.K. Mohammed
, p. 3014 - 3020 (2010)
Five new transition metal complexes [MnL(OAc)]·H2O (1), [FeLCl2] (2), [NiL2]·H2O (3), [CuLCl] (4) and [ZnL2]·2H2O (5) have been synthesized using a tridentate Schiff base ligand, HL (quinoxaline-2-carboxalidine-2-amino-5- methylphenol) and the complexes have been characterized by physicochemical and spectroscopic techniques. The spectral analyses reveal an octahedral geometry for 3, square pyramidal structure for 2 and square planar structure for 4. Analytical and physicochemical data indicate tetrahedral structure for 1 and octahedral structure for 5. The crystallographic study reveals that [NiL 2]·H2O shows distorted octahedral geometry with a cis arrangement of N4O2 donor set of the bis Schiff base and exhibits a two-dimensional polymeric structure parallel to [0 1 0] plane. The complexes were screened for catalytic phenol hydroxylation reaction. Coordinatively unsaturated manganese(II), iron(III) and copper(II) complexes were found to be active catalysts. The poor catalytic activity of the nickel(II) complex is due to coordinatively saturated octahedral nature of the complex. Maximum conversion of phenol was observed for the copper(II) complex and the major product was catechol.
