Structure and Isomerism of Optically Active Complexes

Abstract

Most of the optically active complexes for which experimental and theoretical study has been made involve chelate rings. Thus structure and isomerism of metal chelate complexes will be discussed in this chapter. One of the most striking properties of chelate compounds is their unusual stability due to chelate ring formation. Structures of four-, five-, six- and seven-membered chelate rings have been reported, even eight- and larger membered chelate rings are known. Bonds in chelate rings may arise from two general types of groups: i) primary acid groups in which a metal ion replaces an acid hydrogen and ii) neutral groups which contain an atom with a lone pair suitable for bond-formation. When fíve-membered chelate rings are formed the resulting complex is most stable.