碘捕獲實現的多組分膠囊湧現自組裝
作者:
小柯機器人發布時間:2021/1/3 15:25:15
北京師範大學龔漢元團隊通過碘捕獲實現多組分膠囊湧現自組裝。 相關研究成果發表在2020年12月24日出版的《美國化學會志》。
該文描述了一種三組分自組裝系統,該系統隨著組分變化而改變。該體系包含全烴八芳基大環環[8](1,3-(4,6-二甲基)苯(D4d-CDMB-8)、珊瑚烯(Cora)和I2。無論是在環己烷中還是在不同的結晶條件下,這三種組分的任意兩種之間都沒有明顯的相互作用。但是,當所有三種組分在環己烷中混合後,該體系能夠結晶,得到含有碘的超分子膠囊((D4d-CDMB-8)3(Cora)2)I2。根據單晶和粉末X射線衍射研究以及固態13C核磁共振和拉曼光譜推斷,這種全烴膠囊由三個D4d-CDMB-8和兩個Cora亞基以及一個中心結合的I2分子組成。
這些分析得到了溶液相1H NMR和UV-vis光譜研究的補充驗證。即使在高溫(例如,高達418 K)下,也沒有發現I2從膠囊中逸出的跡象。同樣保護結合的I2不與水溶液(例如飽和NaOH(aq)或Na2S2O3水溶液)中的鹼或標準還原劑反應。還發現,含有3:2摩爾比的D4d-CDMB-8和Cora的混合粉末可以捕獲來自水源(例如,1.0 mM I2 in NaCl(35 wt%)或I2+NaI(aq)(各1.0 mM))的飽和I2蒸汽或碘。目前的系統顯示的結構和功能特徵超出了在簡單的組件分析基礎上的預期。
因此,該文設計了一種構建自組裝結構的有效方法。
附:英文原文
Title: Emergent Self-Assembly of a Multicomponent Capsule via Iodine Capture
Author: Yu-Dong Yang, Xu-Lang Chen, Jonathan L. Sessler, Han-Yuan Gong
Issue&Volume: December 24, 2020
Abstract: Described here is a three-component self-assembly system that displays emergent behavior that differs from that of its constituents. The system comprises an all-hydrocarbon octaaryl macrocycle cyclo[8](1,3-(4,6-dimethyl)benzene (D4d-CDMB-8), corannulene (Cora), and I2. No appreciable interaction is seen between any pair of these three-components, either in cyclohexane or under various crystallization conditions. On the other hand, when all three-components are mixed in cyclohexane and allowed to undergo crystallization, a supramolecular iodine-containing capsule, ((D4d-CDMB-8)3(Cora)2)I2, is obtained. This all-hydrocarbon capsule consists of three D4d-CDMB-8 and two Cora subunits and contains a centrally bound I2 molecule as inferred from single-crystal and powder X-ray diffraction studies as well as solid-state 13C NMR and Raman spectroscopy. These analyses were complemented by solution-phase 1H NMR and UV–vis spectroscopic studies. No evidence of I2 escape from the capsule is seen, even at high temperatures (e.g., up to 418 K). The bound I2 is likewise protected from reaction with alkali or standard reductants in aqueous solution (e.g., saturated NaOH(aq) or aqueous Na2S2O3). It was also found that a mixed powder containing D4d-CDMB-8 and Cora in a 3:2 molar ratio could capture saturated I2 vapor or iodine from aqueous sources (e.g., 1.0 mM I2 in NaCl (35 wt %) or I2 + NaI(aq) (1.0 mM each)). The present system displays structural and functional features that go beyond what would be expected on the basis of a simple sum-of-the-components analysis. As such, it illustrates a new approach to creating self-assembled ensembles with emergent features.
DOI: 10.1021/jacs.0c11838
Source: https://pubs.acs.org/doi/10.1021/jacs.0c11838