Study on the coordination chemistry of asymmetric Schiff base with two amino nitrile chloride

I often because of Schiff base and its complexes with biological activity, catalytic activity, functional properties and luminescence properties in the research field of catalyst, advanced materials and bio medicine are widely used, has aroused the interest of researchers. Asymmetric Schiff base has special properties because of its asymmetric structure. It has important research value and application prospect in the fields of catalysts, fluorescent switches and functional supramolecular design. Compared with the symmetrical Schiff base, asymmetric Schiff base synthesis is relatively difficult and relatively less literature guidance. Preparation of asymmetric Schiff bases and their metal complexes is a challenging task in the search for suitable reaction conditions and synthesis routes. On the basis of research work, asymmetric Schiff base was synthesized by the method of chlorides occupying two amino nitriles, and asymmetric Schiff base complexes were synthesized. The use of two amino maleonitrile and chloride to form a single acylation product of N- acetyl amino maleonitrile shrink two (Ac-DAMN), then Ac-DAMN and salicylaldehyde condensation to form a ligand of N- acetyl -N '- salicylidene amino two maleonitrile (H_2L1); and 2- hydroxy -1- naphthalene was synthesized from acetyl -N ligand N- (2- -1- - hydroxy NAPHTHALDEHYDE) shrink two amino maleonitrile (H_2L2); using two amino maleonitrile and 2- benzoyl chloride reacted to form mono amido N- furoyl shrink two amino maleonitrile (O-DAMN), and then through the condensation of salicylaldehyde ligand N- furoyl -N' - salicylaldehyde two amino maleonitrile (H_2L3). 7 metal complexes were successfully synthesized: complexes ZnL1, CH3OH (1), complexes Co-L2 (2), complexes NiL2, 2CH3OH, CH3CN (3), complexes Cu-L2 (4), complexes Zn-L2 (5), complexes CdL2, CH3CH_2OH (6) and complexes Mn-L2 (). The single crystal structures of complexes (1), (3), (5) and (6) have been obtained and their crystal structures have been analyzed in depth. The complexes (1) by acetyl oxygen atom ligands to form a one-dimensional chain structure; complexes (3) as a single nuclear structure of six coordination complexes; (5) for the symmetric structure, inconsistent with the expected results, the need for further analysis of the causes of the complexes; (6) the hydroxyl oxygen atom coordination the formation of the dual core structure, dual core structure connected by cyano nitrogen atoms, forming a one-dimensional chain structure extension. The experimental results show that the complexes (2) are isomorphic with (3). In this thesis, we also try to synthesize H_2L3 metal complexes, but they do not have their metal complexes, so we need to continue to try. The ligands and complexes were characterized by IR, elemental analysis, nuclear magnetic resonance, UV, fluorescence, thermogravimetry, X ray single crystal diffraction and X ray powder diffraction. The functional properties of the complexes need to be further studied. At present, there are few studies on the design and synthesis of asymmetric Schiff bases by chloride ion occupying method. This study can provide a new idea for the design and synthesis of asymmetric Schiff bases.

Contact US