Project Abstract

Schiff bases are versatile ligands synthesized from the condensation of an amino compound with carbonyl compound and these coordinates to metal ion via azomethine nitrogen. Schiff’s bases and their copper complexes possess remarkable properties as catalysts in various biological systems, polymers, dyes, anti fungal activities anti microbial activities, anti rival activities insectides, anti tumor, cytotoxic activities, plant growth regulator, enzymatic activity and pharmaceutical fields. A variety of Schiff bases and their complexes has been reviewed in this work, the used of Schiff bases as an analytical chemical reagents and separation regents have been stated and discussed.

Project Overview

INTRODUCTIONS

1.0     MEANING OF SCHIFF BASE AND COPPER SCHIFF BASE

1.1     MEANING OF SCHIFF BASE

Schiff bases are condensation products of primary amines and carbonyl compounds, such as aldehyde or ketone. Schiff base was discovered by a German chemist Hugo Schiff in 1864. Schiff bases are considered as one of the most popular families of organic compounds which are used as synthetic intermediates as well as quite helpful in the establishment of coordination chemistry (Gemi, 2004).

Schiff bases are considsed as a very important class of organic compounds, having wide applications in many biological aspects, proteins, visual pigments, enzymic aldolization and delarboxylation reactions. More over some Schiff bases and their metal complexes exhibits antibiotic, antiviral and antitumor agents. They are used as catelysts in polymer and dye industries, beside some uses as antifertility and enzymatic agents. An interesting application of Schiff base is their use as an effective corrosion  inhibitor, which is based on their ability to spontaneously form a monolarger on the surface to be protected, Schiff  bases are also

. .

R1

called imines, and they contain carbon nitrogen

R

double  bond ( C=N-R)(Ozaslen et al, 2011). Due to the physico chemical properties of Schiff bases, they have played a very important role as chelating ligands for transition metal and for the development of coordination chemistry. Since they have flexible nature and easily proton donating property, the study of Schiff bases and their complexes with transition metals, lathanides and radioactive metals has flourished since few decides. Schiff base ligand shows a number of sites for binding that lead to higher coordination polyhedral and cause greater kinetor and thermodynamic stability (A Shral et al, 2001).

1.2     MEANING OF COPPER SCHIFF BASE COMPLEX.

Schiff bases are varstatile Ligants and when they undergo coordinate covalent bonding with a transition metal such as copper a copper –Schiff base complexes are formed.

The Schiff bases has ability to donate core  pair of electron  to the central  metal which is copper, in other to form a complex or coordination compound. Some of the Schiff base has the ability to donate pairs of electron to the copper hence they are called tridentate ligand, those that can donate four pairs of electron are called tetradentate ligand and vice versa. Copper Schiff bases have wide applications in food industry, dye industry, analytical chemistry, catelysis, agrochemical, fungicidal, anti-inflammable activity, anti radical activity and biological activities (Barboin, 2006).

Schiff base complexes are considered to be among the most important sterer chemical models in main group and transition metal coordination chemistry due to their preparative accessibility and structural variety. Copper (11) Complexes shows distorted octahedral and tetrahedral symmetries due to d9 configuration. The distortion is usually seen as axil elongation consistent with the liability and geometric flexibility of the complex (Gemi, 2004).

Therefore typical copper (II) complexes have square planer or square pyramidal geometries with weakly associated ligand in the axial position, but some copper (II) complexes possess regional bipyramidal geometry. The fundamental role of copper and the recognition of its complexes as important bioactivities compounds in vitro and in vivo aroused an ever-increasing interest in these agents as potential drugs for therapeutic intervention in various diseases (Jesmi and Ali, 2010).

A considerable number of Schiff bases copper complexes have potential biological interest, being used as more or less successful models of biological compounds. Not only they have played a seminal role in the development of modern coordination chemistry, but also they can be found at key points in the development of inorganic biochemistry, Catalysis and optical materials (Kumer et al, 2009).