1180-60-5Relevant academic research and scientific papers
Lewis acid-catalyzed synthesis of dodecamethoxycalix[4]arene from 1,3,5-trimethoxybenzene and its conformational behavior and host-guest property
Ogoshi, Tomoki,Kitajima, Keisuke,Umeda, Kenji,Hiramitsu, Sachi,Kanai, Suguru,Fujinami, Shuhei,Yamagishi, Tada-aki,Nakamoto, Yoshiaki
, p. 10644 - 10649 (2009)
Lewis acid-catalyzed condensation of 1,2- and 1,3-dimethoxybenzenes with paraformaldehyde afforded an ortho-bridged cyclic trimer (1) and a meta-bridged cyclic tetramer (2), respectively. Furthermore, condensation of 1,3,5-trimethoxybenzene with paraformaldehyde in the presence of Lewis acid catalyst successfully rendered the first dodecamethoxy-substituted calix[4]arene (3) with high yield. From X-ray crystallography, it was found that 3 formed the partial cone conformation. The conformational behavior of 3 in the solution was investigated by variable temperature 1H NMR measurements. The partial cone structure observed in the solid state was retained in the solution at low temperatures. Furthermore, because of the slow conformational exchanges of 3 on the NMR time scale, bimodal conformational exchanges were found. The host-guest property of 3 with the electron accepting guest, tetracyanoethylene (TCNE) was examined by UV-Vis measurements, and the ability to associate with the 3-TCNE complex was three times higher than that of the 2-TCNE complex. The observation is due to the superior electron donating property and slow conformational exchanges of 3 compared with those of analogous 2.
An electron-transfer induced conformational transformation from non-cofacial "sofa" to cofacial "boat" in cyclotetraveratrylene (CTTV) and formation of charge transfer complexes
Wang, Denan,Ivanov, Maxim V.,Mirzaei, Saber,Lindeman, Sergey V.,Rathore, Rajendra
, p. 5712 - 5717 (2018)
Electro-active polychromophoric assemblies that undergo clam-like electromechanic actuation represent an important class of organic functional materials. Here, we show that the readily available cyclotetraveratrylene (CTTV) undergoes oxidation-induced folding, consistent with interconversion from a non-cofacial "sofa" conformation to a cofacial "boat" conformer. It is found that the non-cofacial "sofa" conformer of CTTV forms stable electron donor-acceptor complexes with chloranil and DDQ. Electron-transfer induced conformational transformation in CTTV provides a framework for the rational design of novel organic functional molecules.
Solvolysis reactions at the 13th carbon of 1-aryl organoiron complexes
Roe, Caroline,Sandoe, Elizabeth J.,Richard Stephenson
, p. 591 - 595 (2010)
Acid-catalysed solvolysis procedures exchange protecting groups on benzyl alcohol derivatives in the synthesis of η5 1-arylcyclohexadienyliron building blocks for alkaloid synthesis. The reaction proceeds via a carbocation intermediate which can also be intercepted by intramolecular electrophilic addition to the tricarbonyl(η4-diene)iron(0) moiety to provide a novel and high-yielding cyclisation reaction forming a 5aα-cyanomethyl-5a,8a-dihydrofluorene tricarbonyliron complex in 96% yield.
A ternary charge-transfer complex composed of cyclotriveratrylene (CTV) and a polyoxometalate (POM) with quinone as an electronic modulator
Tashiro, Shohei,Hashida, Shizuka,Shionoya, Mitsuhiko
, p. 1180 - 1184 (2012)
Triple stack: A facile synthesis of charge-transfer-type crystals composed of CTV and POM was demonstrated. The crystals further accommodated 1,4-benzoquinone as a guest to form a ternary crystal with a donor-acceptor-acceptor arrangement. The electronic spectra of the crystals suggested that the incorporated quinone served as an electronic modulator to adjust the charge-transfer property. Copyright
Silane catecholates: Versatile tools for self-assembled dynamic covalent bond chemistry
Kawakami, Yoshiteru,Ogishima, Tsuyoshi,Kawara, Tomoki,Yamauchi, Shota,Okamoto, Kazuhiko,Nikaido, Singo,Souma, Daiki,Jin, Ren-Hua,Kabe, Yoshio
, p. 6066 - 6069 (2019)
Shape-persistent macrocycles and 3D nanocages have been prepared in one-pot under MeCN-promoted dynamic covalent bond conditions starting from silane catecholates, whose structures were confirmed by X-ray crystallography. Cation-exchange reactions of macrocycles and nanocages were performed along with the encapsulation of ammonium ions within the cavity of an anionic macrocycle and a tetrahedral nanocage.
Single-crystal-to-single-crystal transformation of the desolvation of a cyclotriveratrylene-acetonitrile inclusion complex: Via a gating mechanism with subsequent polymorphism
Payne, Richard M.,Oliver, Clive L.
, p. 7965 - 7971 (2016)
A cyclotriveratrelyne-acetonitrile inclusion complex is shown to undergo a single-crystal-to-single-crystal transformation upon desolvation to an intermediate phase and it is furthermore demonstrated that the preparation conditions may introduce polymorphism of the apohost. We characterised the as-synthesized and desolvated polymorphs using single crystal (polymorph 1) and powder X-ray diffraction, thermal analysis and gas sorption. Successive data collections on the as-synthesized crystal at 50 °C show that the rotation of a single, unique methoxy group of the host molecule may allow evacuation of solvent molecules from the seemingly non-porous crystal.
Hydrogen-bonded molecular capsules: Probing the role of water molecules in capsule formation in modified cyclotricatechylene
Illa, Giri Teja,Hazra, Sohan,Satha, Pardhasaradhi,Purohit, Chandra Shekhar
, p. 4759 - 4765 (2017/08/22)
Two new pyridine moiety-appended cavitands, CTC(Py)2(OH)2 and CTC(Py)3, were synthesized and characterized. The solid state structures of both cavitands were studied by single crystal X-ray diffraction. CTC(Py)2(OH)2 resulted in a hydrogen-bonded dimeric molecular capsule, entrapping two molecules of DMSO and intervening water molecules that formed hydrogen bonding to DMSO and CTC(Py)2(OH)2. When crystallized in the absence of water, it forms a 2D polymer by hydrogen bonding of pyridine nitrogen and phenolic hydrogen atoms. CTC(Py)3 forms no such capsule.
Homochiral columns constructed by chiral self-sorting during supramolecular helical organization of hat-shaped molecules
Roche, Cécile,Sun, Hao-Jan,Prendergast, Margaret E.,Leowanawat, Pawaret,Partridge, Benjamin E.,Heiney, Paul A.,Araoka, Fumito,Graf, Robert,Spiess, Hans W.,Zeng, Xianbingon,Ungar, Goran,Percec, Virgil
supporting information, p. 7169 - 7185 (2014/06/09)
A library of dendronized cyclotriveratrylene (CTV) crowns substituted with chiral, racemic, or achiral peripheral alkyl chains, including enantiopure R and S branched alkyls, "racemic by mixture", "racemic by synthesis", n-octyl, and n-dodecyl groups was synthesized. In solvophobic solvents and in bulk they self-assemble in helical columns. Their solution and bulk shape-persistent supramolecular structures were determined by a complementary combination of circular dichroism (CD) and UV in solution and thin film, microspot CD in thin film, differential scanning calorimetry combined with fiber X-ray diffraction, computer simulation, and molecular models. In solution, self-assembly via a cooperative mechanism generates single-handed columns from enantiopure CTVs and mixtures of right-and left-handed columns from racemic by mixture, racemic by synthesis, other combinations of R and S, and even from achiral compounds. In bulk state all supramolecular columns form a 3D hexagonal crystalline phase, φhk (P63 symmetry), that can be obtained only from single-handed columns and a columnar hexagonal 2D liquid crystal, φh. The highest order φhk consists of enantiopure single-handed columns that are slightly distorted 12-fold triple helices. The "hat-shaped" dendronized CTV assembles in bent-branch pine-tree columns that allow interdigitation of alkyl groups in adjacent columns regardless of their direction. Enantiomerically rich, racemic, and achiral compositions undergo deracemization in the crystal state by transfer of the transient disc-like conformer of dendronized CTV from column to column during crown inversion. Solid state NMR experiments identified motional processes that allow such transfer. This unprecedented supramolecular chiral self-sorting will impact the creation of functions in complex systems.
Synthesis of cycloveratrylene macrocycles and benzyl oligomers catalysed by bentonite under microwave/infrared and solvent-free conditions
Miranda, Rene,Valencia-Vazquez, Omar,Maya-Vega, Carlos Abel,Nicolas-Vazquez, Ines,Vargas-Rodriguez, Yolanda Marina,Morales-Serna, Jose Antonio,Garcia-Rios, Erendira,Salmon, Manuel
, p. 12820 - 12844 (2013/11/06)
Tonsil Actisil FF, which is a commercial bentonitic clay, promotes the formation of cycloveratrylene macrocycles and benzyl oligomers from the corresponding benzyl alcohols in good yields under microwave heating and infrared irradiation in the absence of solvent in both cases. The catalytic reaction is sensitive to the type of substituent on the aromatic ring. Thus, when benzyl alcohol was substituted with a methylenedioxy, two methoxy or three methoxy groups, a cyclooligomerisation process was induced. Unsubstituted, methyl and methoxy benzyl alcohols yielded linear oligomers. In addition, computational chemistry calculations were performed to establish a validated mechanistic pathway to explain the growth of the obtained linear oligomers.
Self-assembly of dendritic crowns into chiral supramolecular spheres
Percec, Virgil,Imam, Mohammad R.,Peterca, Mihai,Wilson, Daniela A.,Heiney, Paul A.
supporting information; experimental part, p. 1294 - 1304 (2009/06/28)
The synthesis and structural and retrostructural analysis of a library of dendronized cyclotriv- eratrylene containing seven nonchiral and sevenchiral self-assembling dendrons is reported. These dendronized cyclotri veratrylenes exhibit a crown conformation that we named dendritic crown.Selected examples of dendritic crowns self-assemble into helical pyrami dal columns that self-organize into columnar crystals or into 2-D columnar hexagonal lattices with intracolumnar order. A second group of dendritic crowns self-assembles into helical pyramidal columns and spherical supramolecular dendrimers that self- organize into cubic and tetragonal lattices. A third group of dendritic crowns self-assembles only in spherical supramolecular dendrimers. The helical pyramidal columns and spherical supramolecular dendrimers assembled from dendronized cyclotriveratrylene containing nonchiral dendrons are chiral but racemic while those generated from chiral dendrons exhibit amplified chirality. Structural analysis by a combination of X-ray diffraction methods and CD experiments demonstrated a new mechanism for the assembly of chiral supramolecular spheres that involves an intramolecular structure containing short fragments of helical pyramidal columns.
