The copper(II) complexes formed by the imidazolinone herbicide imazapyr [(+/-)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid] were studied in aqueous solution by potentiometric and spectroscopic techniques. Imazapyr acts as a chelating molecule and is effective over a wide pH range. The chelating set active in acidic media involves rather weak donors, namely the pyridine and imidazole nitrogens. In neutral media, the lactam site of the imidazolinone ring deprotonates and the ligand takes advantage of a rather basic nitrogen atom, which, assisted by the pyridine donor, yields stable complexes with five-coordination at the metal ion.
Copper(II) complexes of the imidazolinone herbicide imazapyr / Duda, Am; Dyba, M; Kozlowski, H; Micera, Giovanni; Pusino, Alba. - In: JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. - ISSN 0021-8561. - 44:11(1996), pp. 3698-3702. [10.1021/jf9507856]
Copper(II) complexes of the imidazolinone herbicide imazapyr
MICERA, Giovanni;PUSINO, Alba
1996-01-01
Abstract
The copper(II) complexes formed by the imidazolinone herbicide imazapyr [(+/-)-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid] were studied in aqueous solution by potentiometric and spectroscopic techniques. Imazapyr acts as a chelating molecule and is effective over a wide pH range. The chelating set active in acidic media involves rather weak donors, namely the pyridine and imidazole nitrogens. In neutral media, the lactam site of the imidazolinone ring deprotonates and the ligand takes advantage of a rather basic nitrogen atom, which, assisted by the pyridine donor, yields stable complexes with five-coordination at the metal ion.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.