Department of Chemistry, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Department of Applied Chemistry, National Chi Nan University, 1 Daxue Rd., Puli, Nantou County, 545, Taiwan.
Sci Rep. 2017 Jun 16;7(1):3649. doi: 10.1038/s41598-017-03684-y.
Three dendrimers, (t-Bu-G N) , CC(t-Bu-G N) and (t-Bu-G N) , with 3,5-di-tert-butyl amidobenzene as a common peripheral moiety were prepared in 64-83% yields and characterized. The bulk solids had high BET surface areas of 136-138 m/g, which were similar for the three dendrimers in spite of their different molecular weight (ranging from 1791 to 2890). It was concluded that the peripheral amide groups do not imbed in the interstitial space of neighbouring dendrimer molecules but rather build a supramolecular architecture through strong intermolecular H-bonds. This mode of assembly generates voids in the bulk dendrimers responsible for sorption properties. The X-ray crystal structure analysis of a compound representing the peripheral moiety of the dendrimers and the FT-IR and powder-XRD data for (t-Bu-G N) suggest the proposed supramolecular structure. The isosteric heats of CO sorption (Q ) for (t-Bu-G N) were significantly higher than those for the other two dendrimers, which is consistent with the formation of a different type of voids within the interstitial space of the molecule. It is suggested that the interstitial void space can be designed and tuned to adjust its properties to a particular task, such as the separation of gases or a catalytic reaction facilitated by the dendrimer.
三种树枝状分子，（t-Bu-G N）、CC（t-Bu-G N）和（t-Bu-G N），以 3,5-二叔丁基酰胺苯为常见的外围部分，以 64-83%的产率合成并进行了表征。块状固体具有高达 136-138 m/g 的 BET 表面积，这对于三种树枝状分子来说是相似的，尽管它们的分子量不同（范围从 1791 到 2890）。结论是，外围酰胺基团不会嵌入相邻树枝状分子的间隙空间，而是通过强分子间氢键构建超分子结构。这种组装模式在块状树枝状聚合物中产生了负责吸附性能的空隙。代表树枝状聚合物外围部分的化合物的 X 射线晶体结构分析以及（t-Bu-G N）的 FT-IR 和粉末 XRD 数据表明了所提出的超分子结构。（t-Bu-G N）对 CO 的等吸附热（Q）明显高于另外两种树枝状分子，这与分子间隙内形成不同类型的空隙一致。可以设计和调整间隙空隙空间，以调整其性能以适应特定任务，例如气体分离或通过树枝状聚合物促进的催化反应。
