5509-08-0Relevant articles and documents
Diverse Proton-Conducting Nanotubes via a Tandem Macrocyclization and Assembly Strategy
Strauss, Michael J.,Jia, Manping,Evans, Austin M.,Castano, Ioannina,Li, Rebecca L.,Aguilar-Enriquez, Xavier,Roesner, Emily K.,Swartz, Jeremy L.,Chavez, Anton D.,Enciso, Alan E.,Stoddart, J. Fraser,Rolandi, Marco,Dichtel, William R.
supporting information, p. 8145 - 8153 (2021/06/21)
Macrocycles that assemble into nanotubes exhibit emergent properties stemming from their low dimensionality, structural regularity, and distinct interior environments. We report a versatile strategy to synthesize diverse nanotube structures in a single, efficient reaction by using a conserved building block bearing a pyridine ring. Imine condensation of a 2,4,6-triphenylpyridine-based diamine with various aromatic dialdehydes yields chemically distinct pentagonal [5 + 5], hexagonal [3 + 3], and diamond-shaped [2 + 2] macrocycles depending on the substitution pattern of the aromatic dialdehyde monomer. Atomic force microscopy and in solvo X-ray diffraction demonstrate that protonation of the macrocycles under the mild conditions used for their synthesis drives assembly into high-aspect ratio nanotubes. Each of the pyridine-containing nanotube assemblies exhibited measurable proton conductivity by electrochemical impedance spectroscopy, with values as high as 10-3 S m-1 (90% R.H., 25 °C) that we attribute to differences in their internal pore sizes. This synthetic strategy represents a general method to access robust nanotube assemblies from a universal pyridine-containing monomer, which will enable systematic investigations of their emergent properties.
Cooperative Self-Assembly of Pyridine-2,6-Diimine-Linked Macrocycles into Mechanically Robust Nanotubes
Strauss, Michael J.,Asheghali, Darya,Evans, Austin M.,Li, Rebecca L.,Chavez, Anton D.,Sun, Chao,Becker, Matthew L.,Dichtel, William R.
supporting information, p. 14708 - 14714 (2019/11/05)
Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length and mechanical
Equilibration of Imine-Linked Polymers to Hexagonal Macrocycles Driven by Self-Assembly
Chavez, Anton D.,Evans, Austin M.,Flanders, Nathan C.,Bisbey, Ryan P.,Vitaku, Edon,Chen, Lin X.,Dichtel, William R.
supporting information, p. 3989 - 3993 (2018/03/01)
Macrocycles based on directional bonding and dynamic covalent bond exchange can be designed with specific pore shapes, sizes, and functionality. These systems retain many of the design criteria and desirable aspects of two-dimensional (2D) covalent organi
FeCl3-catalyzed self-cleaving deprotection of methoxyphenylmethyl-protected alcohols
Sawama, Yoshinari,Masuda, Masahiro,Asai, Shota,Goto, Ryota,Nagata, Saori,Nishimura, Shumma,Monguchi, Yasunari,Sajiki, Hironao
, p. 434 - 437 (2015/03/03)
4-Methoxyphenylmethyl ethers are widely utilized as alcohol protecting groups. FeCl3 effectively catalyzes the deprotection of methoxyphenylmethyl-type ethers in a self-cleaving manner to produce oligomeric derivatives and alcohols. Remarkably, the highly pure mother alcohols can be obtained without silica gel column chromatography by using the 2,4-dimethoxyphenylmethyl group as a protective group.
Synthesis of structural analogues of hexadecylphosphocholine and their antineoplastic, antimicrobial and amoebicidal activity
Timko, Luká?,Fischer-Fodor, Eva,Garajová, Mária,Mrva, Martin,Chereches, Gabriela,Ondriska, Franti?ek,Bukovsky, Marián,Luká?, Milo?,Karlovská, Janka,Kubincová, Janka,Devínsky, Ferdinand
, p. 263 - 273 (2015/05/26)
Twelve derivatives of hexadecylphosphocholine (miltefosine) were synthesized to determine how the position and length of the alkyl chain within the molecule influence their biological activities. The prepared alkylphosphocholines have the same molecular formula as miltefosine. Activity of the compounds was studied against a spectrum of tumour cells, two species of protozoans, bacteria and yeast. Antitumour efficacy of some alkylphosphocholines measured up on MCF-7, A2780, HUT-78 and THP-1 cell lines was higher than that of miltefosine. The compounds showed antiprotozoal activity against Acanthamoeba lugdunensis and Acanthamoeba quina. Some of them also possess fungicidal activity against Candida albicans equal to miltefosine. No antibacterial activity was observed against Staphylococcus aureus and Escherichia coli. A difference in position of a long hydrocarbon chain within the structure with maximum efficacy was observed for antitumour, antiprotozoal and antifungal activity.
Rapid configuration analysis of the solenopsins
Pianaro, Adriana,Fox, Eduardo G.P.,Bueno, Odair C.,Marsaioli, Anita J.
experimental part, p. 635 - 642 (2012/09/22)
A protocol for rapid access to the relative and absolute configurations of the solenopsins, the venom alkaloids of fire ants (Solenopsis spp.), was developed based on chiral capillary gas chromatography. The synthesis of racemic mixtures of 2-methyl-6-alkylpiperidines and the isolation of natural (2R,6R)- and (2R,6S)-2-methyl-6-undecylpiperidines allowed for the standardization of the chromatographic method. Application of this protocol revealed the previously unknown natural occurrence of four stereoisomers of 2-methyl-6-undecylpiperidine in venom samples from workers and gynes of Solenopsis saevissima.
Synthetic organic electrochemistry in ionic liquids: The viscosity question
Bornemann, Steven,Handy, Scott T.
experimental part, p. 5963 - 5974 (2011/09/13)
Ionic liquids are obvious candidates for use in electrochemical applications due to their ionic character. Nevertheless, relatively little has been done to explore their application in electrosynthesis. We have studied the Shono oxidation of arylamines and carbamates using ionic liquids as recyclable solvents and have noted that the viscosity of the medium is a major problem, although with the addition of sufficient co-solvent, good results and excellent recovery and recycling of the ionic liquid can be achieved.
Copper-catalyzed cross-coupling reaction of organoboron compounds with primary alkyl halides and pseudohalides
Yang, Chu-Ting,Zhang, Zhen-Qi,Liu, Yu-Chen,Liu, Lei
supporting information; experimental part, p. 3904 - 3907 (2011/05/15)
Non-activated alkyl electrophiles, including alkyl iodides, bromides, tosylates, mesylates, and even chlorides, underwent copper-catalyzed cross-coupling with aryl boron compounds and alkyl 9-BBN reagents (see scheme; 9-BBN=9-borabicyclo[3.3.1]nonane). The reactions proceed with practically useful reactivities and thus complement palladium- and nickel-catalyzed Suzuki-Miyaura coupling reactions of alkyl halides.
Amphiphilic organocatalyst for schotten-baumann-type tosylation of alcohols under organic solvent free condition
Asano, Keisuke,Matsubara, Seijiro
supporting information; experimental part, p. 1757 - 1759 (2009/09/06)
A Tosylation of primary alcohol with tosyl chloride was performed effectively with an W-hexadecylimidazole catalyst in water containing K 2CO3 aggregation of the catalyst carrying a hydrophobic methylene chain worked as a substitute for organic solvent.
Mild and efficient indium metal catalyzed synthesis of sulfonamides and sulfonic esters
Kim, Joong-Gon,Doo, Ok Jang
, p. 2501 - 2504 (2008/02/13)
A facile and efficient method for synthesizing sulfonamides was developed using a catalytic amount of indium metal. A wide range of sulfonamides were synthesized in excellent yields using the new process. The method showed a generality for substrates including less nucleophilic and sterically hindered anilines, and it is also applicable for preparing sulfonic esters from sulfonyl chlorides and alcohols. Georg Thieme Verlag Stuttgart.
