Co-Crystal Formation of Partially Fluorinated 1,3,5-Tris(phenylethynyl)benzenes

Abstract

Several rigid 1,3,5-tris(phenylethynyl)benzenes with different fluorination patterns were synthesized through selective Sonogashira-Hagihara coupling reactions to analyze the packing behavior in solid-state structures. The aggregation is dominated by various intermolecular interactions between aryl substituents, triple bonds, C−H bonds and H⋅⋅⋅F contacts. Co-crystallization experiments for the analysis of preferred aryl-aryl-interactions led to 1 : 1 complexes. Intermolecular phenyl-perfluorophenyl interactions with short centroid-centroid distances are dominating these co-crystal structures. They lead to melting point increases of up to 49 °C for the co-crystals compared to the pure substances.