Template and Related Reactions

Metal template reactions may be defined as reactions involving ligands which require, or can be significantly enhanced by, a particular geometrical orientation imposed by co-ordination to a metal. Many metal template reactions have resulted in the synthesis of macrocyclic compounds, such 

Sigwart, P. Kroneck, and P. Hemmerich, Helv. Chim. Acta, 1970, 53, 177. 

Busch has reviewed these Helv. Chim. Acta, 1967, A. Werner centennial edition, 174. 

Several types of enzyme involved in amino-acid metabolism (including aminotransferases and decarboxylases) require pyridoxal phosphate (7, PLP) as co-factor. It has been postulated that all such reactions involve the formation of a Schiff-base intermediate between the amino-acid and (7) as the first step. Simple systems containing metal ion, amino-acid, and 

Leussing and co-workers have studied other enzyme-model systems, such as the dimerization of pyruvate catalysed by Ni and Zn . The kinetics and mechanism of the hydrolysis of AT-salicylideneaniline in the presence of metal ions have also been reported, and Gansow and Holm 

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