BACKGROUND Quinoline derivatives possess excellent fungicidal activity against rice blast, but quinoline derivatives have not been thoroughly explored as fungicides. In the process of designing new fungicides, the 1,1,1,2,3,3,3‐heptafluoropropan‐2‐yl group was introduced in order to find new structure quinoline derivatives. RESULTS Seventeen new quinoline derivatives containing 1,1,1,2,3,3,3‐heptafluoropropan‐2‐yl moiety were designed and synthesised. In vivo fungicidal activities of these compounds were tested against rice blast. Some of the compounds provided effective control at 100 mg L−1, and a few compounds were effective at 10 mg L−1. Furthermore, a density functional theory study established the structure–activity relationships of the synthesised compounds. CONCLUSION Quinoline derivatives, especially benzyl (2,3,8‐trimethyl‐6‐(perfluoropropan‐2‐yl)quinolin‐4‐yl) carbonate, which possess good control effective against rice blast and cucumber powdery mildew, may become new lead compounds for the development of fungicides with further structure modification. © 2017 Society of Chemical Industry