Design, Synthesis and Herbicidal Activities of Tetrahydroisoindoline‐1,3‐dione Derivatives Containing Alkoxycarbonyl Substituted 2‐Benzoxazolinone

Abstract Several different alkoxycarbonyl‐substituted 2‐benzoxazolinone moieties have been incorporated into a tetrahydroisoindoline‐1,3‐dione scaffold to provide 25 compounds (1a–1u and 2a–2d). The structures of these compounds were confirmed by 1H and 13C NMR, HRMS and X‐ray single‐crystal diffraction. Some of these compounds (1g, 1h, 1j, 1k) exhibited excellent herbicidal activities against Abutilon theophrasti, Amaranthus retroflexus and Echinochloa crus‐galli at a rate of 375 g AI·ha−1. Among them, compounds 1h and 1j displayed the best post‐emergence herbicidal effect against Abutilon theophrasti with ED50 values of 1.8 and 5.3 g AI·ha−1, respectively, which are superior to that of the commercial acifluorfen (44.3 g AI·ha−1). Field trials demonstrated that compound 1h exhibited similar herbicidal activity to a high concentration atrazine, and found to be safer for maize than atrazine. The results of this study therefore show that compound 1h could potentially be used as a post‐emergence herbicide for maize fields.