Te Aka Matua, School of Science, University of Waikato, Hamilton 3240, New Zealand.
Molecules. 2022 Nov 7;27(21):7634. doi: 10.3390/molecules27217634.
The crystal structures of 1-(2,3,5,6-tetrafluoro-4-pyridyl)-3-benzylimidazolium chloride (1) and iodide (3) have been determined by single crystal X-ray diffraction. The crystal structure of 1 is similar to that of the bromide salt (2), possessing anion···C5F5N···C6H5 motifs, whilst that of 3 contains columns of alternating iodide anions and parallel tetrafluoropyridyl rings. All three crystal structures possess C(1)−H∙∙∙X− and C(2)−H∙∙∙X− hydrogen bonding. DFT calculations reveal that the strengths of the hydrogen bonding interactions lie in the order C(1)−H···X− > C(3)−H···X− > C(2)−H···X− for the same halide (X−) and Cl− > Br− > I− for each position. It is suggested that salt 3 adopts a different structure to salts 1 and 2 because of the larger size of iodide.
1-(2,3,5,6-四氟-4-吡啶基)-3-苄基咪唑𬭩氯化物(1)和碘化物(3)的晶体结构 通过单晶 X 射线衍射法测定。
标题:1-(2,3,5,6-四氟-4-吡啶基)-3-苄基咪唑𬭩氯化物(1)和碘化物(3)的晶体结构 通过单晶 X 射线衍射法测定。
1-(2,3,5,6-四氟-4-吡啶基)-3-苄基咪唑𬭩氯化物(1)和碘化物(3)的晶体结构已通过单晶 X 射线衍射法确定。1 的晶体结构与溴化物盐(2)相似,具有阴离子···C5F5N···C6H5 基序,而 3 则包含交替的碘化物阴离子和平行的四氟吡啶环的列。所有三个晶体结构都具有 C(1)−H∙∙∙X−和 C(2)−H∙∙∙X−氢键。DFT 计算表明,氢键相互作用的强度顺序为 C(1)−H···X− > C(3)−H···X− > C(2)−H···X−,对于相同的卤化物(X−)和 Cl− > Br− > I−,对于每个位置。由于碘化物的尺寸较大,建议盐 3 采用与盐 1 和 2 不同的结构。