Study On The Synthesis Of Imazamox

Imazamox is a kind of Imidazolinone herbicides utilised in soybean field, which is developed and manufactured in American Cyanamid Company. In this paper, 1-amino-1,2-ethylenedicarboxylic acid esters was obtained from the reactants of diethyl maleate and hydroxylamine hydrochloride via addition and dehydration. The above product was reacted with methoxymethacrolein to produce 5-(methoxymethyl)-2,3-pyridinedicarboxylate; Methoxymethacrolein was synthesized from acrolein, methanol and formaldehyde. The intermediate 5-(methoxymethyl)-2,3-pyridine dicarboxylate further formed 5-(methoxymethyl)-2,3-pyridine dicarboxylic acid anhydride after hydrolysis, acidification and hydration reactions. Streker reaction was carried out in order to obtain another intermediate of 2-amino-2,3-dimethylbutyronitrile using 3-methylbutanone, ammonia chloride and sodium cyanide as the materials. Finally, Imazamox was synthesized by 2-amino-2,3-dimethylbutyronitrile and 5-(methoxymethyl)-2.3-pyridine dicarboxylic acid anhydride after addition, cyclodehydration, and acidification. The main mechanisms and influencing factors such as reaction temperature, reaction time, and the ratios of reactants are discussed here, in order to determine the optimum conditions for this total synthesis. The target product and some of the important intermediates were characterized by MS and'H NMR.