A series of novel carboxamide compounds containing benzoxazole motif was synthesized through multiple steps, including electrophilic substitution, cyclization, reduction and amide formation. These processes utilized ortho-aminophenol and heptafluoro-2-iodopropane as starting materials. The structures of these compounds (4a–4r) were characterized by 1H NMR, 13C NMR, and HRMS. Bioassay results revealed that most of these compounds exhibited significant insecticidal activity against Mythimna separata at 500 mg/L. Among them, compound 6-chloro-N-(4-methoxy-3-(6-(perfluoropropan-2-yl)benzo[d]oxazol-2-yl)phenyl)-N-methylnicotinamide (4r) possessed the highest activity, even at 4 mg/L. Molecular docking predicted the binding modes of 4r. These novel carboxamide compounds containing benzoxazole motifs offer valuable insights for designing insecticidal compounds targeting GABA receptors, aiming to control lepidopteran pests effectively. [ABSTRACT FROM AUTHOR]