Tolpyralate is an imidazolinone based herbicide which may be used in crop prevention.
ChEBI: 1-({1-ethyl-4-[3-(2-methoxyethoxy)-2-methyl-4-(methylsulfonyl)benzoyl]-1H-pyrazol-5-yl}oxy)ethyl methyl carbonate is a benzoylpyrazole that is 1H-pyrazole substituted by an ethyl, 3-(2-methoxyethoxy)-2-methyl-4-(methylsulfonyl)benzoyl, and 1-[(methoxycarbonyl)oxy]ethoxy groups at positions 1, 4 and 5, respectively. It is an aromatic ether, a benzoylpyrazole, a carbonate ester, a member of toluenes, an aromatic ketone and a sulfone.
Tolpyralate is produced commercially through a modular aromatic-coupling route. Manufacturers first prepare the pyrimidinedione core, then introduce the chloro-substituted phenyl ether fragment through controlled nucleophilic aromatic substitution. The resulting intermediate is refined, coupled to the trifluoromethyl-bearing side chain, and purified to technical-grade active ingredient. Industrial steps focus on achieving the correct crystalline form, removing halogenated by products, and ensuring stability before the material is milled and sent to formulation.
Inhibition of the 4-hydroxyphenylpyruvate dioxygenase (HPPD) enzyme
