C 19 H 17 Cl 2 N 3 O 3 ,monoclinic, C2/c (no. 15), a =25.792(7) Å, b =10.020(3) Å, c =15.054(4) Å, b =93.337(5)°, Source of materialThetitle compound is easily available by aliterature known synthesis [1]. It was recrystallized from am ethyl tert. butyle ther solution at room temperature to give colourless crystals suitable for single-crystal X-ray diffraction. Experimental detailsHa toms were positioned geometrically with C-H =0 .93, 0.97 and 0.96 Åfor aromatic, methylene and methyl, respectively, and constrained to ride on their parent atoms, with U iso (H) =1.2 (1.5 for methyl)times U eq (C). Difenoconazoleisanimportant representative of atriazole derivative, which has been used as the most efficient triazole fungicide [5,6]. But alot of waste residues are formed in the process of production. In order to get deeper insight into the reaction mechanism and to optimize the production process, the title compound wass eparated andi ts structure was characterized. As shown in thefigure,fourrings exist in the molecular structure. Two benzene rings and triazol ring are planar, while the dioxolan ring is bent. The dihedral angle between two benzene rings is 80.6°ow-ing to rotating and bending of the ether bond. The dioxolan ring adopts an envelope conformation, with the C17 atom deviating from the C18/O2/C13/O3 plane by 0.248(2) Å.Z. Kristallogr.

C 15 H 10 ClNO 3 ,monoclinic, P2