| Abstract
| - As part of a study of metal ion effects on chemicaltransformations of nitrogen-containing agrochemicals,conversion of daminozide to succinate via cleavage of thehydrazide C−N bond was examined in the presence andabsence of divalent metal ions. No conversion was observedin metal ion-free solutions or in the presence of 1.0 mMNiII, ZnII, and PbII. CuII, in contrast, markedly increased ratesof daminozide to succinate conversion. Halide ions (Cl-,Br-) had no effect on daminozide conversion in the absenceof metal ions but markedly increased conversion ratesobserved in the presence of CuII. The nitrogen-donor ligandsethylenediamine, N-(2-hydroxyethyl)ethylenediamine, and1,4,7,10-tetraazacyclododecane decreased rates of CuII-facilitated conversion, while 1,5,9-triazacyclododecaneactually increased rates of conversion. H NMR and UVspectroscopy provide evidence for the formation of 1:1 CuII−daminozide complexes. Halide ion effects and nitrogen-donor ligand effects point to an oxidative mechanism for CuII-facilitated daminozide breakdown, rather than hydrolysis.The structurally related compound butyric acid 2,2-dimethylhydrazide (BH) is subject to the same CuII-facilitated breakdown via an oxidative mechanism. N,N-Dimethylsuccinamic acid (SA), in contrast, breaks down viaa hydrolytic mechanism.
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