A New Paradigm for the Supramolecular Structure of Laterally Offset Diarenes: Polymorphs II of Para‐Substituted Acetophenone Azines, YpPh(Me)CNNC(Me)PhYp (Y = Cl, Br, CH3)

Abstract

The crystal structures of polymorphs II of acetophenone azines YpPhRCNNCRPhYp with R = CH3 and Y = Cl (1M), Br (2M), and CH3 (8M) are discussed. The azine molecules in polymorphs II are Ci‐symmetric with trans‐azine moieties and conrotatory phenyl twists. Polymorphs 1M‐I and 2M‐I contain C2‐symmetric enantiomers with pronounced azine twists and disrotatory phenyl twists and allow for strong lateral double T‐contacts. The three polymorphs II exemplify the new Paradigm IV for the supramolecular architectures of “laterally offset diarenes” and result in “shiplap/flat” idioteloamphiphile monolayers. Intralayer lateral attraction is provided by edge‐to‐face arene‐arene contacts between molecules with substantial longitudinal offset and involves arene edges bridging one azine‐N and one phenyl center (EAzArB synthon) or one phenyl center and substituent Y (EYArB synthon) of different neighbors. These bridging synthons are characterized by a survey of pertinent structure parameters and their structural significance is corroborated by analysis of distance mapped Hirshfeld surfaces and the computation of 2D‐fingerprint plots. The edge‐to‐face contacts are the most attractive intermolecular interactions, and these interactions are quantified via the computed pair interaction energies and the results of aromatic analyzer analysis. Synthon binding energies and lattice energies are determined to assess polymorph preference energies.