Pillar[5]arene-Based [2]Rotaxane: Synthesis, Characterization, and Application in a Coupling Reaction

Abstract

Mechanically interlocked molecules are a class of smart supramolecular species because of their interesting topological structure and application in various areas, such as biology and nanoscience. In this work, we used "multicomponent reaction" to fabricate a new [2]rotaxane based on pillar[5]arene from different small-sized molecules. The molecular structure of the obtained [2]rotaxane R was confirmed by 1 H and 13 C NMR, high-resolution electrospray ionization mass spectrometry, twodimensional nuclear Overhauser effect spectroscopy, and density functional theory studies. Interestingly, the [2]rotaxane-based organometallic cross-linked catalyst (Pd@R) was easily constructed via the coordination between triazole groups and Pd(NO 3 ) 2 . Pd@R proved to be a good catalyst for the Suzuki−Miyaura coupling reaction with excellent stability and repeatability.

External-stimulus-triggered conformational inversion of mechanically self-locked pseudo[1]catenane and gemini-catenanes based on A1/A2-alkyne–azide-difunctionalized pillar[5]arenes

“…Mp 161-162 C. 1 31.6, 33.8, 55.5, 55.5, 55.5, 55.6, 55.7, 55.9, 56.2, 68.3, 74.7, 79.7, 113.3, 113.4, 113.5, 113.9, 114.3, 114.8, 128.0, 128.1, 128.2, 128.3, 128.3, 128.5, 128.6, 128.7, 148.8, 150.3, 150.4, 150.5, 150.6, 150.7 Copper(I)-catalyzed alkyne-azide 1,3-dipolar cycloaddition reaction of 1-(10-bromodecyloxy)-4-propargylpillar [5]arene Pillar-3M and Pillar-3D(1-2). 14,25 Pillar-2 (100 mg, 0.1 mmol) was dissolved in dry acetone (30 mL) and degassed for 5 min. Thereaer, a degassed solution of tetrakis(acetonitrile)copper(I) hexauorophosphate, Cu(CH 3 CN) 4 PF 6 (18.4 mg, 0.048 mmol) and tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA, 26.4 mg, 0.048 mmol) in acetonitrile (1.5 mL) was added.…”

“…Importantly, this reaction exhibits an excellent functional group tolerance, in addition to being compatible with a wide range of substrates. [24][25][26][27][28][29][30][31][32][33] Thus, we report the synthesis of a pseudo [1]catenane base of self-inclusion A1/A2-asymmetric difunctionalized pillar [5]arenes. In solution, stable pseudo [1]rotaxanes that are formed from the self-inclusion of the straight-chain bromodecyl group on the pillar [5]arene rim, enable the construction of pseudo [1]catenane and gemini-catenane structures via the conversion of bromine to an azide functional group followed by intramolecular CuAAC reaction.…”

Recent Progress in Light-Driven Molecular Shuttles

“…Recently, mechanically interlocked molecules (MIMs) have received widespread attention for their well-defined and unique interlocked structures and appealing stimuli-responsive properties in various fields particularly in artificial molecular machines and nanoscience (Erbas-Cakmak et al, 2015;Stoddart 2017;Sun et al, 2019;Dattler et al, 2020;Cai et al, 2021). Rotaxane is one type of the most crucial representative of MIMs, which is often composed of an axle component interlocked by a macrocyclic wheel component (Ma and Tian, 2010;Guo et al, 2020). Conventionally, the axle component contains two bulky end groups as stoppers to protect the wheel component from dethreading.…”

Enhancing the Stability and Photothermal Conversion Efficiency of ICG by Pillar[5]arene-Based Host-Guest Interaction

“…Pillar [5]arenes (Ogoshi et al, 2008;Xue et al, 2012;Ogoshi et al, 2019), composed of hydroquinone or its derivatives bridged by-CH 2in the 2,5-positions, are a smart type of macro-cyclic hosts after crown ethers (Yoo et al, 2019;Zhou et al, 2017), cyclodextrins (Lai et al, 2017), calixarenes (Li et al, 2020), and cucurbiturils (Jiang et al, 2020;Chernikova and Berdnikova, 2020). The preparation and modification of pillar [5]arene is convenient and efficient, which make them outstanding affinity hosts for selectively guests (Chao et al, 2020;Duan et al, 2020;Hao et al, 2020;Sheng et al, 2020;Xu et al, 2020;Guo et al, 2020a;Guo et al, 2020b;Cao et al, 2021;Chen et al, 2021;Shin et al, 2021). Considering the convenient synthesis of pillar[n]arenes and their rich hostguest properties, functional materials based on pillar[n]arenes have been widely studied and applied in various fields, such as drug delivery systems (Cai et al, 2021;Yao et al, 2017;Xiao et al, 2019), molecular machines (Han et al, 2020;Dong et al, 2014;Wan et al, 2020), trans-membrane channels (Chen et al, 2013;Strilets et al, 2020), and supramolecular polymeric materials (Xiao et al, 2018;Jie et al, 2020;Zhang et al, 2020).…”