N , N '-二芳基方酰胺和N , N '-二烷基方酰胺是构象稳定的连接体,分别具有延伸(反式,反式)和折叠(顺式,顺式)结构,与外部条件无关。在这里,我们表明,N-单甲基化的N , N '-二芳基方酰胺在晶体中通常采用(反式,顺式)结构,但在溶液中表现出依赖于溶剂的构象平衡。特别地,N-甲基-N , N'-双(1-萘基)方酰胺( 1f )的稳定构象异构体根据溶剂而变化。因此,芳香族N-单甲基化方酰胺可作为环境响应型分子开关的组分。
N , N '-二芳基方酰胺和N , N '-二烷基方酰胺是构象稳定的连接体,分别具有延伸(反式,反式)和折叠(顺式,顺式)结构,与外部条件无关。在这里,我们表明,N-单甲基化的N , N '-二芳基方酰胺在晶体中通常采用(反式,顺式)结构,但在溶液中表现出依赖于溶剂的构象平衡。特别地,N-甲基-N , N'-双(1-萘基)方酰胺( 1f )的稳定构象异构体根据溶剂而变化。因此,芳香族N-单甲基化方酰胺可作为环境响应型分子开关的组分。
N,N'-Bis(ortho-substituted phenyl)squaramides afforded chiral crystals, in which squaramide molecules are arranged in one-handed helical networks, upon simple recrystallization. Three types of crystals with different helices were obtained, depending on the substituents or recrystallization solvent. Folded-type intermolecular hydrogen-bonding interactions of squaramides play a key role in forming the helical networks. (C) 2019 Elsevier Ltd. All rights reserved.