Template reactions of 1,4-bis(α-carboxybenzylidenehydrazino)phthalazine with cobalt(II), nickel(II), and chromium(III)

Abstract

1,4-Bis(α-carboxybenzylidenehydrazino)phthalazine (1) has been prepared from 1,4-dihydrazinophthalazine and the methyl ester of phenylglyoxylic acid. The reaction of (1) with cobalt(II) and nickel(II) gives isostructural macrocyclic complexes [(2a) and (2b)] as a result of the template effect of these metal ions. In the case of the chromium(III) ion, a similar template reaction has not been observed, which is proposed to be due to the six-co-ordinate environment adopted by the Cr^III ion. Mass, i.r., n.m.r., and u.v.–visible data of the novel compounds are presented.