1711-46-2Relevant academic research and scientific papers
Metal ion-catalyzed Diels-Alder and hydride transfer reactions. Catalysis of metal ions in the electron-transfer step
Fukuzumi, Shunichi,Ohkubo, Kei,Okamoto, Toshihiko
, p. 14147 - 14155 (2002)
Rates of Diels - Alder cycloaddition of anthracenes with p-benzoquinone and its derivatives as well as rates of hydride-transfer reactions from 10-methyl-9,10-dihydroacridine to the same series of p-benzoquinones are accelerated significantly in the presence of metal ions in acetonitrile. An extensive comparison of the catalytic effects of metal ions in electron transfer from one-electron reductants (cobalt tetraphenylporphyrin and decamethyrferrocene) to p-benzoquinones with those in the Diels - Alder reactions of the quinones as well as the hydride-transfer reactions has revealed that the catalysis of metal ions in each case is ascribed to the 1:1 and 1:2 complexes formed between the corresponding semiquinone radical anions and metal ions. The transient absorption and ESR spectra of the semiquinone radical anion-metal ion complexes are detected directly in the electron-transfer reduction of p-benzoquinone derivatives in the presence of metal ions. The catalytic reactivities of a variety of metal ions in each reaction are well correlated with the energy splitting values of πg levels because of the complex formation between O2.- andMn+, which are derived from the gzz values of the ESR spectra of the O2.--Mn+ complex.
Finely Tuning the Free Volume Architecture in Iptycene-Containing Polyimides for Highly Selective and Fast Hydrogen Transport
Luo, Shuangjiang,Wiegand, Jennifer R.,Kazanowska, Barbara,Doherty, Cara M.,Konstas, Kristina,Hill, Anita J.,Guo, Ruilan
, p. 3395 - 3405 (2016)
Iptycene-based polyimides have attracted extensive attention recently in the membrane gas separation field due to their unique structural hierarchy and chemical characteristics that enable construction of well-defined yet tailorable free volume architecture for fast and selective molecular transport. We report here a new series of iptycene-based polyimides that are exquisitely tuned in the monomer structure to afford preferred microcavity architecture for hydrogen transport. In particular, a triptycene-containing dianhydride (TPDAn) was prepared to react with two iptycene-containing diamines (i.e., TPDAm and PPDAm) or 2,2′-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (6FAP) to produce entirely or partially iptycene-based polyimides. The incorporation of iptycene units effectively disrupted chain packing, which resulted in ultrafine microporosity in the membranes with a desired bimodal size distribution with maxima at ~3 and ~7 ?, respectively. Depending on the combination of diamine and dianhydride, the microporosity was feasibly tuned and optimized to meet the needs of challenging H2 separations, especially for H2/N2 and H2/CH4 gas pairs. Particularly, a H2 permeability of 27 barrers and H2/N2 and H2/CH4 selectivities of 142 and 300, respectively, were obtained for TPDAn-6FAP.
Hybrid Molecular Container Based on Glycoluril and Triptycene: Synthesis, Binding Properties, and Triggered Release
Liu, Wenjin,Lu, Xiaoyong,Xue, Weijian,Samanta, Soumen K.,Zavalij, Peter Y.,Meng, Zihui,Isaacs, Lyle
, p. 14101 - 14110 (2018)
We designed and synthesized a “hybrid” molecular container 1, which is structurally related to both cucurbit[n]uril (CB[n]) and pillar[n]arene type receptors. Receptor 1 was fully characterized by 1H NMR, 13C NMR, IR, MS and X-ray single crystal diffraction. The self-association behavior, host–guest recognition properties of 1, and the [salt] dependence of Ka were investigated in detail by 1H NMR and isothermal titration calorimetry (ITC). Optical transmittance and TEM measurements provide strong evidence that receptor 1 undergoes co-assemble with amphiphilic guest C10 in water to form supramolecular bilayer vesicles (diameter 25.6±2.7 nm, wall thickness ≈3.5 nm) that can encapsulate the hydrophilic anticancer drug doxorubicin (DOX) and the hydrophobic dye Nile red (NR). The release of encapsulated DOX or NR from the vesicles can be triggered by hexamethonium (8 c) or spermine (10) which leads to the disruption of the supramolecular vesicles.
Synthesis of highly sulfonated poly(arylene ether sulfone)s with sulfonated triptycene pendants for proton exchange membranes
Gong, Feixiang,Mao, Hongchao,Zhang, Yuwei,Zhang, Suobo,Xing, Wei
, p. 1738 - 1747 (2011)
A series of poly(aryl ether sulfone)s containing triptycene groups PES-x-TPD (x refers to molar percentage of TPD) were firstly synthesized through nucleophilic aromatic substitution polycondensation by using 2,5-triptycenediol (TPD), bis(4-hydroxyphenyl) sulfone (BHPS) and 4,4′-difluorodiphenyl sulfone (DFDPS). The sulfonation of copolymers was conducted at room temperature by using a mild sulfonating reagent (98% H2SO4), and the degree of sulfonation was readily and accurately controlled by adjusting the ratio of TPD and BHPS. The structures of PES-x-TPD and SPES-x-TPD were characterized by IR, 1H NMR and 13C NMR spectra. These ionomers generally showed high thermal stability and mechanical strength at low humidity regardless of high IEC value. Meanwhile, it is noteworthy that these novel SPES-x-TPD membranes with high IEC value achieved high proton conductivity in a wide range of humidity at 80 °C. For example, SPES-60-TPD with the highest IEC value 2.86 mmol/g displays the conductivity of 2.5 × 10 -1 S/cm which is much higher than that of the perfluorinated Nafion membrane (1.1 × 10-1 S/cm) at 80 °C and 94% RH. At 80 °C and 34% RH, SPES-60-TPD displays the conductivity of 4.5 × 10 -3 S/cm which is also higher than that of the Nafion membrane (3.0 × 10-3 S/cm). Microscopic analyses revealed that well-dened phase separated structures and uniform ionic pathway was formed for SPES-45-TPD membrane with the IEC of 2.29 mmol/g. Moreover, a H2/O2 fuel cell using the SPES-55-TPD (IEC = 2.68 mmol/g) also showed better performance than that of Nafion 117 at 40 °C and 30% RH.
Melt-phase synthesis and properties of triptycene-containing copolyesters
Liu, Yanchun,Turner, S. Richard,Wilkes, Garth
, p. 4049 - 4056 (2011)
A new triptycene diol (TD), triptycene-1,4-hydroquinone-bis(2-hydroxyethyl) ether, was synthesized and was used to prepare a series of copolyesters with dimethyl 1,4-cyclohexanedicarboxylate (1,4-DMCD) by melt polycondensation. Straight chain aliphatic spacers, including ethylene glycol (EG), 1,4-butanediol (BD), and 1,6-hexanediol (HD), were used as codiols with TD to explore the effects of straight chain flexible spacers on copolyester properties. A concomitant series of non-triptycene copolyesters based on hydroquinone bis(2-hydroxyethyl) ether (HBE), bis[4-(2-hydroxyethoxy)phenyl] sulfone (BHPS), 1,1-bis[4-(2-hydroxyethoxy)phenyl]cyclohexane (BHPC), or 1,1-bis(2- hydroxyethoxy)phenyl-3,3,5-trimethylcyclohexane (BHPT) were prepared for comparison. The results demonstrated that the triptycene-containing polyesters in this study have higher thermal stability and higher glass transition temperatures (Tg's) than the corresponding non-triptycene analogues. For triptycene-containing copolyesters, the mechanical properties were found to be dependent on the types and compositions of comonomer diols. A 1,4-butanediol-based triptycene copolyester was observed to have a significant increase in Tg and modulus while maintaining high elongation at ambient temperature (23 °C). However, all the studied 1,4-butanediol-based copolyesters were brittle and had comparable modulus values at low temperatures (-25 or -40 °C).
Blurring the Lines between Host and Guest: A Chimeric Receptor Derived from Cucurbituril and Triptycene
Lu, Xiaoyong,Samanta, Soumen K.,Zavalij, Peter Y.,Isaacs, Lyle
supporting information, p. 8073 - 8078 (2018/06/04)
We report the synthesis and X-ray crystal structure of a cucurbituril–triptycene chimeric receptor (1). Host 1 binds to guests typical of CB[6]–CB[8], but also binds to larger guests such as blue box (20) and the Fujita square (22). Intriguingly, the geom
Preparation and gas transport properties of triptycene-containing polybenzoxazole (PBO)-based polymers derived from thermal rearrangement (TR) and thermal cyclodehydration (TC) processes
Luo, Shuangjiang,Liu, Junyi,Lin, Haiqing,Kazanowska, Barbara A.,Hunckler, Michael D.,Roeder, Ryan K.,Guo, Ruilan
, p. 17050 - 17062 (2016/11/11)
Polybenzoxazoles (PBOs), such as thermally rearranged (TR) polymers, have been shown to have excellent gas separation performance. Herein we report the preparation and transport properties of two new series of PBO-based polymers that were thermally derived from triptycene-containing o-hydroxy polyimide and polyamide precursors via a thermal rearrangement (TR) process and a thermal cyclodehydration (TC) process, respectively. Incorporation of triptycene units into poly(hydroxyimide) precursor structures led to a significant increase of fractional free volume and created ultrafine microporosity in the converted PBO-based TR polymers, which enabled both high gas permeabilities and high selectivities. Although the TC process of the poly(hydroxyamide) precursor led to moderate improvement in the separation performance of the resulting triptycene-containing PBO polymers as compared to the TR process, the PBO films converted via the TC process exhibited excellent mechanical properties superior to many other TR polymers previously reported in the literature as well as the triptycene-containing TR polymers in this study. In particular, the PBO film thermally rearranged at 450 °C showed a H2 pure gas permeability of 810 barrer, a CO2 permeability of 270 barrer, and CO2/CH4 and H2/CH4 selectivities of 67 and 200, respectively, at 35 °C and 11 atm, which are far beyond the upper bound limits.
TRIPTYCENE MONOMER AND TRIPTYCENE CONTAINING POLYESTERS AND POLYURETHANES
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Paragraph 0042-0044, (2015/07/15)
The primary diol triptycene derivative triptycene-1,4-hydroquinone-bis(2-hydroxyethyl) ether (TD) is provided, as are methods of using the same to synthesize polyesters and polyurethanes, and polyesters and polyurethanes synthesized therewith.
Electrosynthesis and electrochromic properties of poly(amide-triarylamine)s containing triptycene units
Hsiao, Sheng-Huei,Chiu, Yu-Ting
, p. 90941 - 90951 (2015/11/11)
Four bis(amide-triarylamine) derivatives featuring a triptycene as an interior core and terminal electroactive triphenylamine (TPA) or N-phenylcarbazole (NPC) groups were prepared by the condensation reactions from 1,4-bis(4-aminophenoxy)triptycene with 4-carboxytriphenylamine and N-(4-carboxyphenyl)carbazole, respectively, and from 1,4-bis(4-carboxyphenoxy)triptycene with 4-aminotriphenylamine and N-(4-aminophenyl)carbazole, respectively. The electrochemistry and electropolymerization of these bis(amide-triarylamine) derivatives were investigated. The stability of the oxidized forms of the bis(amide-triarylamine)s is affected by the orientation of amide linkage and the structure of terminal triarylamine unit. Two of the bis(amide-triarylamine)s could be electropolymerized into robust films on the electrode surface in an electrolyte solution. The electrogenerated polymer films exhibited reversible electrochemical oxidation processes and strong color changes upon electro-oxidation, which can be switched by potential modulation. The electrochromic properties of the films were evaluated by the spectroelectrochemical and electrochromic switching studies. The TPA-based film showed better electrochromic performance than the NPC-based one.
Synthesis and characterization of triptycene-based polyimides with tunable high fractional free volume for gas separation membranes
Wiegand, Jennifer R.,Smith, Zachary P.,Liu, Qiang,Patterson, Christopher T.,Freeman, Benny D.,Guo, Ruilan
, p. 13309 - 13320 (2014/08/18)
Robust polymer membranes that are highly permeable and selective are desired for energy efficient gas separation processes. In this study, a series of rigid, bulky triptycene-based diamine monomers were designed, synthesized, and subsequently incorporated into the backbone of polyimides via polycondensation with 2,2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) to obtain a series of polyimide membranes with high fractional free volume. These triptycene-containing polyimides with systematic variations in their chemical structure demonstrate the viability of the 'tunable' fractional free volume by introducing various substituents onto the polymer backbone. All the polyimides synthesized exhibited film-forming high molecular weight, high solubility, and excellent thermal properties, with glass transition temperatures ranging from 280 °C to 300 °C and thermal stability up to 500 °C. Compared to other classes of glassy polymers, these triptycene-polyimides had high combinations of permeability and selectivity, suggesting that a favorable free volume size distribution in these triptycene polyimides was induced by the unique chain packing mechanism of triptycene units. The correlation between gas transport properties and the polymer chemical structure was also investigated. Altering the size of the substituents neighboring the triptycene units provides greater opportunity to fine-tune the fractional free volume and free volume size distribution in the polymer, which in turn can change the transport properties effectively to meet various separation needs. It is expected that additional design modifications made by exploiting the chemistry versatility of the triptycene moiety and by selectively adding other components may improve these membranes to break the gas permeability-selectivity trade-off barrier. This journal is the Partner Organisations 2014.
