Four‐, five‐ and six‐coordinated transition metal complexes based on naphthalimide Schiff base ligands: Synthesis, crystal structure and properties. (23rd June 2017)

• Record Type: Journal Article
• Authors: Xu, Yuling; Zhang, Han; Shen, Kesheng; Mao, Shanshan; Shi, Xinkui; Wu, Huilu
• Is Part Of: Applied organometallic chemistry. Volume 32:Number 1(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-06-23
• Subjects: antioxidant -- crystal structure -- fluorescence -- naphthalimide Schiff base -- transition metal complexes; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.3902
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : Two bidentate Schiff base ligands (HL 1 = N ‐ n ‐butyl‐4‐[( E )‐2‐(((2‐aminoethyl)imino)methyl)phenol]‐1, 8‐naphthalimide; and HL 2 = N ‐ n ‐butyl‐4‐[( E )‐2‐(((2‐aminoethyl)imino)methyl)‐6‐methoxyphenol]‐1, 8‐naphthalimide) with their metal complexes [Cu(L 1 )2 ] (1 ), [Zn(L 1 )2 (Py)]2 ⋅H2 O (2 ) and [Ni(L 2 )2 (DMF)2 ] (3 ) have been synthesized and characterized. Single‐crystal X‐ray structure analysis reveals that complex1 has a four‐coordinated square geometry, while complex2 is a five‐coordinated square pyramidal structure and complex3 is a distorted six‐coordinated octahedral structure. Cyclic voltammograms of1 indicate an irreversible Cu 2+ /Cu + couple. In vitro antioxidant activity assay demonstrates that the ligands and the two complexes1 and3 display high scavenging activity against hydroxyl (HO ) and superoxide (O2 − ) radicals. Moreover, the fluorescence properties of the ligands and complexes1 –3 were studied in the solid state. Metal‐mediated enhancement is observed in2, whereas metal‐mediated fluorescence quenching occurs with1 and3 . Abstract : Three transition metal complexes based on naphthalimide Schiff base ligands have been synthesized and characterized systematically. The complexes and ligands have a strong potential to be applied as scavengers to eliminate radicals. Complex2 has excellent fluorescence properties.