Synthesis and Characterization of Bis-Chelate and Macrocyclic Complexes of Copper and Zinc
MetadataShow full item record
In the past two decades considerable time has been spent in the study of metalmacrocyclicJ complexes, complexes in which the ligand completely encompasses the metal, (see figure 1). The main reason for this intense interest in macrocyclic complexes was the recognition of the inherent efficiency of the many natural biological processes which are catalyzed by proteins. For example, the production of ammonia from N2 by many plants is catalyzed by nitrogenase. In an attempt to mimic the catalytic ability of these proteins many organo-transition metal macrocyclic complexes have been synthesized and studied. These complexes normally contain the metal or metals which are thought to occupy the active site of the protein of interest, (e.g., iron in hemoglobin). The metal is surrounded by an organic macrocyclic ligand which is thought to be a good model of the active site of the protein. Macrocyclic ligands are usually used in this type of study for several reasons: 1 ) macrocyclic complexes are usually substitution inert, i. e., the metal will normally remain in its original position while the complex undergoes a reaction, 2) macrocyclic complexes are able to undergo oxidation or reduction while maintaining their structural integrity, 3) changes in the macro cyclic framework can be easily done and usually have a significant effect on the behavior of the metal atom.