O−H···N Heterosynthon: A Robust Supramolecular Unit For Crystal Engineering

To explore the robust nature of template resorcinols in organic solid-state reactions, a series of mono- and dipyridines were cocrystallized with different substituted resorcinols. The organizational consequences of hydrogen-bonds in the hydroxyl···pyridine heterosynthon in the presence of competitive hydrogen-bonding functional groups are elucidated. C−O bond flexibility, steric hindrance, and formation of undesired intramolecular hydrogen bonds have strongly affected the ability of the template for a parallel alignment of olefins. Finally, structural changes that occurred at a molecular level during [2 + 2] photodimerization of the complex of 1,4-bis[(E)-2-(4-pyridyl)ethenyl]-2-fluorobenzene (bpef) with 2,4-dihydroxy-benzaldehyde were studied in detail by performing a rather rare single-crystal-to-single-crystal photoirradiation.

为探究模板型间苯二酚（template resorcinols）在有机固态反应中的固有稳健特性，本研究将一系列单吡啶与联吡啶类化合物与不同取代基修饰的间苯二酚进行共结晶。研究阐明了在竞争性氢键官能团共存条件下，羟基-吡啶异合成子（hydroxyl···pyridine heterosynthon）中氢键的分子组装调控效应。碳氧键（C−O bond）的柔性、空间位阻效应以及非预期形成的分子内氢键，均对模板调控烯烃平行排布的能力造成了显著影响。最后，通过开展极为罕见的单晶-单晶（single-crystal-to-single-crystal）光辐照实验，对1,4-双[(E)-2-(4-吡啶基)乙烯基]-2-氟苯（bpef）与2,4-二羟基苯甲醛形成的配合物发生[2+2]光二聚反应（[2 + 2] photodimerization）过程中，分子层面的结构变化进行了详尽研究。