Mechanochemical Complexation of Diethyl N,NA′-[1,3-(2-methyl)phenyl]dioxalamate and Resorcinol: Conformational Twist and X-Ray Helical Supramolecular Architecture

The cocrystal formed by diethyl N,NA '-[1,3-(2-methyl)phenyl]dioxalamate (1) and resorcinol (2), namely 1 center dot 2 (cryst) (C21H24N2O8) was prepared by mechanochemical complexation. IR spectroscopy and powder X-ray diffraction studies allowed to determine the complexation and the conformational switching of the ethyl oxalamate side arms. In the crystal structure of 1 center dot 2 (cryst) , complexation occurs through O-H center dot center dot center dot O=C hydrogen-bonding interactions with the participation of phenolic O-H as donor and amide carbonyl group as acceptor. The steric hindrance of the CH3 group in the C-2 position of the aromatic ring leads to a meso-helical supramolecular architecture forming a C (2) (2) (16) chain motif. Crystal data: monoclinic, C2/c space group, a = 34.9054(13) , b = 8.0434(5) , c = 5.1577(8) , beta = 97.521(3)A degrees. The cocrystal formed by diethyl N,NA '-[1,3-(2-methyl)phenyl]dioxalamate and resorcinol, prepared by mechanochemical complexation.