100-76-5Relevant articles and documents
Cucurbit[7]uril host-guest complexes of cholines and phosphonium cholines in aqueous solution
Wyman, Ian W.,Macartney, Donal H.
, p. 253 - 260 (2010)
The neutral host cucurbit[7]uril forms very stable complexes with a series of cationic cholines (R3NCH2CH2OR'+) and their phosphonium analogues (R3PCH2CH 2OR'+) (R3 = Me3, Et3, or Me2Bz, or R3N = quinuclidinium, and R' = H, COCH 3, CO(CH2)2CH3, or PO3H), and (±)-carnitine, in aqueous solution. The complexation behaviour has been investigated using 1H and 31P NMR spectroscopies, and ESI mass spectrometry. The complexation-induced chemical shift changes of the guests clearly indicate the effects of replacing the N(CH3) 3+ end group by P(CH3)3+, and changing the nature of R on the position of the guest with respect to the CB[7] cavity and its polar portal-lining carbonyl groups. This study demonstrates that molecular recognition of cholines in aqueous solution is achievable with a neutral host without the need for aromatic walls for cation-π interactions. The Royal Society of Chemistry 2010.
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Clemo,Metcalfe
, p. 1989 (1937)
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The Soft Molecular Polycrystalline Ferroelectric Realized by the Fluorination Effect
Xie, Yongfa,Ai, Yong,Zeng, Yu-Ling,He, Wen-Hui,Huang, Xue-Qin,Fu, Da-Wei,Gao, Ji-Xing,Chen, Xiao-Gang,Tang, Yuan-Yuan
, p. 12486 - 12492 (2020)
For a century ferroelectricity has attracted widespread interest from science and industry. Inorganic ferroelectric ceramics have dominated multibillion dollar industries of electronic ceramics, ranging from nonvolatile memories to piezoelectric sonar or ultrasonic transducers, whose polarization can be reoriented in multiple directions so that they can be used in the ceramic and thin-film forms. However, the realization of macroscopic ferroelectricity in the polycrystalline form is challenging for molecular ferroelectrics. In pursuit of low-cost, biocompatible, and mechanically flexible alternatives, the development of multiaxial molecular ferroelectrics is imminent. Here, from quinuclidinium perrhenate, we applied fluorine substitution to successfully design a multiaxial molecular ferroelectric, 3-fluoroquinuclidinium perrhenate ([3-F-Q]ReO4), whose macroscopic ferroelectricity can be realized in both powder compaction and thin-film forms. The fluorination effect not only increases the intrinsic polarization but also reduces the coercive field strength. More importantly, it is also, as far as we know, the softest of all known molecular ferroelectrics, whose low Vickers hardness of 10.5 HV is comparable with that in poly(vinylidene difluoride) (PVDF) but almost 2 orders of magnitude lower than that in BaTiO3. These attributes make it an ideal candidate for flexible and wearable devices and biomechanical applications.
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Van Paasschen,Geanangel
, p. 2321 (1976)
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Degradation of Organic Cations under Alkaline Conditions
You, Wei,Hugar, Kristina M.,Selhorst, Ryan C.,Treichel, Megan,Peltier, Cheyenne R.,Noonan, Kevin J. T.,Coates, Geoffrey W.
supporting information, p. 254 - 263 (2020/12/23)
Understanding the degradation mechanisms of organic cations under basic conditions is extremely important for the development of durable alkaline energy conversion devices. Cations are key functional groups in alkaline anion exchange membranes (AAEMs), and AAEMs are critical components to conduct hydroxide anions in alkaline fuel cells. Previously, we have established a standard protocol to evaluate cation alkaline stability within KOH/CD3OH solution at 80 °C. Herein, we are using the protocol to compare 26 model compounds, including benzylammonium, tetraalkylammonium, spirocyclicammonium, imidazolium, benzimidazolium, triazolium, pyridinium, guanidinium, and phosphonium cations. The goal is not only to evaluate their degradation rate, but also to identify their degradation pathways and lead to the advancement of cations with improved alkaline stabilities.
Synthesis of amino-diamondoid pharmacophores: Via photocatalytic C-H aminoalkylation
Weigel, William K.,Dang, Hoang T.,Yang, Hai-Bin,Martin, David B. C.
supporting information, p. 9699 - 9702 (2020/09/03)
We report a direct C-H aminoalkylation reaction using two light-activated H-atom transfer catalyst systems that enable the introduction of protected amines to native adamantane scaffolds with C-C bond formation. The scope of adamantane and imine reaction partners is broad and deprotection provides versatile amine and amino acid building blocks. Using readily available chiral imines, the enantioselective synthesis of the saxagliptin core and rimantadine derivatives is also described.
