150258-68-7Relevant academic research and scientific papers
Hydrolysis Kinetics of Thifensulfuron Methyl in Aqueous Buffer Solutions
Cambon, Jean-Pierre,Bastide, Jean
, p. 333 - 337 (1996)
The hydrolysis of thifensulfuron methyl and thifensulfuron were investigated in buffered aqueous solutions with pH values of 4, 5, 9, and 10. Hydrolysis of thifensulfuron methyl was pH dependent and relatively fast both in acidic and alkaline buffer solutions. In the case of thifensulfuron, hydrolysis rates were of the same order of magnitude as thifensulfuron methyl at acidic pH, but very low at alkaline pH. In acidic solutions, cleavage of the sulfonylurea bridge and O-demethylation of the methoxy group of the triazine ring occurred concurrently. The resulting intermediates gave two parallel reactions: cleavage of the sulfonylurea bridge and opening of the triazine ring. The relative rates of the different hydrolysis pathways were influenced by the pKaof compounds. At alkaline pH, thifensulfuron methyl hydrolyzed to thifensulfuron, which was slowly transformed by cleavage of the sulfonylurea bridge and O-demethylation.
Rearrangement products in aqueous photolysis of thifensulfuron methyl
Sharma, Ashok K.,Ryan, David L.,Marr, Nina L.,Wadsley, Michael P.,Cheatham, Steve F.
, p. 401 - 410 (2017)
Photo-degradation of [14C]-thifensulfuron methyl has been investigated in aqueous media using a light source which simulates sunlight. Degradation of thifensulfuron methyl proceeds predominantly via sulfonylurea bridge ipso-contraction, and via cleavage of the bridge structure, to yield products in which the thiophene and the triazine rings have disconnected. One significant degradation product, which accounts for nearly 10%, retained both rings with truncated bridge moiety. Surprisingly, this product had thiophene ring substituents rearranged from their original locations. Other laboratories have reported photodegradation of thifensulfuron-methyl, and identified similar degradation products as well. The structure of the rearrangement product has been misidentified in previous reports because the rearrangement of the thiophene ring is not widely recognized. An unambiguous identification of this product and potential rearrangement mechanisms are presented in this report.
