**Chapter 9 175**

Preface

The Schiff base is a well-known organic compound category and a typical organic ligand for metal complexes in both organic and inorganic chemistry. However, development in material and life sciences using Schiff base compounds is still ongoing.

Each chapter presents various viewpoints of Schiff base in current developments: overview and synthesis of organic chemistry; metal complexes with structures, aromatic ligand, bioactive core, cytotoxic activity as inorganic chemistry, chemosensors for heavy metal ions and catalytic applications as applied chemistry. The information summarized in this book will be useful for all readers who are interested in Schiff

From where is such a variety? Indeed, imine or azomethine (C∙N) of Schiff base is merely a functional group, which is usually synthesized from aldehyde and (primary) amine. However, introducing extended groups into aldehyde or amine is easy. Therefore, as a lone pair donating group (Lewis base) coordinating with a metal ion to yield metal complexes, Schiff base (ligands) and their metal complexes can obtain different functions or properties. For example, azobenzene containing salen-type metal complexes have been used as photo-functional dyes dispersing into polymer films. Besides coordination to metal ions as a rigid chelate ligand, introducing an azobenzene group and strong pi-conjugated planar moiety plays an essential role in polarized light-induced control of the molecular orientation, which was also investigated with DFT calculation theoretically. As for material science use, the stability of Schiff base ligands has advantages. We used redox active Schiff base metal complexes (potentially exhibiting catalytic function) for electron transfer mediator to a metalloenzyme. In this case, the reactivity of the Schiff base metal complex plays an important role. As for catalytic or biochemical reactions towards assisting life science, reactivity should be considered during molecular design.

At glance, stability and reactivity are opposite requirements, though Schiff base (ligands) can realize both by molecular design. Thus, Schiff base compounds have

**Takashiro Akitsu**

Tokyo, Japan

Department of Chemistry, Tokyo University of Science,

wide applications and are at the frontier of chemistry.

This book provides a comprehensive overview of Schiff base chemistry.

base and their metal complexes.

Schiff Base Complexes for Catalytic Application *by Shakeel Nawaz Shariff, Supriya Saravu and Dileep Ramakrishna*
