TY - JOUR
T1 - Synthesis, spectral, electrochemical, crystal structures and nonlinear optical properties of unsymmetrical Ni(II) and Cu(II) Schiff base complexes
AU - Cisterna, Jonathan
AU - Dorcet, Vincent
AU - MANZUR NAZAL, CECILIA CAROLINA
AU - Ledoux-Rak, Isabelle
AU - Hamon, Jean René
AU - Carrillo, David
N1 - Funding Information:
The authors thank Dr S. Sinbandhit (CRMPO, Rennes) and Prof. P. Grez (PUC Valparaiso) for helpful assistance with NMR experiments and stimulating discussion of the electrochemical data, respectively. This research has been performed as part of the Chilean-French International Associated Laboratory for “Inorganic Functional Materials” (LIAMIF-CNRS No. 836). Financial support from the Fondo Nacional de Desarrollo Científico y Tecnológico [FONDECYT (Chile), Grant No. 1130105 (D.C., C.M. and M.F.), the Vicerrectoría de Investigación y Estudios Avanzados, Pontificia Universidad Católica de Valparaíso, Chile (D.C., C.M. and M.F.), the CNRS and the Université de Rennes 1 is gratefully acknowledged. J. C. thanks the CONICYT (Chile) for support of a graduate fellowship.
Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - This paper explores the synthesis, spectroscopic and structural characterization, linear and nonlinear optical properties, as well as the electrochemical behavior of two series of robust neutral Ni(II)- and Cu(II)-centered organometallic macroacyclic salen-type Schiff base complexes, namely, the 5-nitrosubstituted derivatives M[Fc-C(O)CH = C(CH3)N-o-C6H4-N = CH-(2-O,5-NO2-C6H3)] (M = Ni (2), Cu (3)), and their 3,5-difluorosubstituted analogues M[Fc-C(O)CH = C(CH3)N-o-C6H4-N = CH-(2-O-3,5-F2-C6H2)] (M = Ni (4), Cu (5); Fc = ferrocenyl = (η5-C5H5)Fe(η5-C5H4))). Compounds 2-5 were synthesized in good yields (75-87%) in refluxing ethanol for 4 h, via template reaction by condensation of the tridentate half-unit metalloligand Fc-C(O)CH = C(CH3)-N(H)-o-C6H4NH2 (1) with 5-nitrosalicylaldehyde and 3,5-difluorosalicylaldehyde, respectively, in the presence of hydrated nickel(II) and copper(II) acetate salts, respectively. Their composition and identity were inferred from elemental analysis, FT-IR, UV-Vis, and multinuclear NMR spectroscopy. Single crystal X-ray diffraction analysis of the two 3,5-difluorosubstituted compounds 4 and 5 indicates a slightly bowed structure of the unsymmetrical Schiff base scaffold. Both Ni2+ and Cu2+ ions are tetracoordinated in a distorted square planar environment, with two nitrogen atoms and two oxygen atoms as donors. The electrochemical behavior of the four binuclear complexes was investigated by cyclic voltammetry, showing greater anodic shifts of the reversible redox process ascribed to the FeII/FeIII couple of the ferrocenyl donor fragment of the 5-nitrosubstituted derivatives compared to their 3,5-difluorosubstituted counterparts. Harmonic Light Scattering measurements showed that compounds 2-5 exhibited rather high second-order nonlinear responses, found between 200 and 267 × 10-30 esu, establishing a good correlation between redox potentials and the hyperpolarizability β1.91 values.
AB - This paper explores the synthesis, spectroscopic and structural characterization, linear and nonlinear optical properties, as well as the electrochemical behavior of two series of robust neutral Ni(II)- and Cu(II)-centered organometallic macroacyclic salen-type Schiff base complexes, namely, the 5-nitrosubstituted derivatives M[Fc-C(O)CH = C(CH3)N-o-C6H4-N = CH-(2-O,5-NO2-C6H3)] (M = Ni (2), Cu (3)), and their 3,5-difluorosubstituted analogues M[Fc-C(O)CH = C(CH3)N-o-C6H4-N = CH-(2-O-3,5-F2-C6H2)] (M = Ni (4), Cu (5); Fc = ferrocenyl = (η5-C5H5)Fe(η5-C5H4))). Compounds 2-5 were synthesized in good yields (75-87%) in refluxing ethanol for 4 h, via template reaction by condensation of the tridentate half-unit metalloligand Fc-C(O)CH = C(CH3)-N(H)-o-C6H4NH2 (1) with 5-nitrosalicylaldehyde and 3,5-difluorosalicylaldehyde, respectively, in the presence of hydrated nickel(II) and copper(II) acetate salts, respectively. Their composition and identity were inferred from elemental analysis, FT-IR, UV-Vis, and multinuclear NMR spectroscopy. Single crystal X-ray diffraction analysis of the two 3,5-difluorosubstituted compounds 4 and 5 indicates a slightly bowed structure of the unsymmetrical Schiff base scaffold. Both Ni2+ and Cu2+ ions are tetracoordinated in a distorted square planar environment, with two nitrogen atoms and two oxygen atoms as donors. The electrochemical behavior of the four binuclear complexes was investigated by cyclic voltammetry, showing greater anodic shifts of the reversible redox process ascribed to the FeII/FeIII couple of the ferrocenyl donor fragment of the 5-nitrosubstituted derivatives compared to their 3,5-difluorosubstituted counterparts. Harmonic Light Scattering measurements showed that compounds 2-5 exhibited rather high second-order nonlinear responses, found between 200 and 267 × 10-30 esu, establishing a good correlation between redox potentials and the hyperpolarizability β1.91 values.
KW - Copper
KW - Crystal structure
KW - NO-ligand
KW - Nickel
KW - Nonlinear optics
KW - Schiff base complexes
UR - http://www.scopus.com/inward/record.url?scp=84924972178&partnerID=8YFLogxK
U2 - 10.1016/j.ica.2015.02.030
DO - 10.1016/j.ica.2015.02.030
M3 - Article
AN - SCOPUS:84924972178
VL - 430
SP - 82
EP - 90
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
SN - 0020-1693
ER -