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Search for "supramolecular" in Full Text gives 501 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
A switchable [2]rotaxane with two active alkenyl groups
Beilstein J. Org. Chem. 2018, 14, 2074–2081, doi:10.3762/bjoc.14.181
- polymers. Keywords: alkenyl bond; functional crown ether; stimuli-responsiveness; switchable rotaxane; Introduction Along with the development of supramolecular chemistry, much attention has been paid to the design and synthesis of novel and complicated mechanical interlocked molecules (MIMs) [1][2][3][4
- , which act as important precursors for constructing stimuli-responsive supramolecular materials [21][22]. Rotaxanes [23][24][25][26][27][28][29][30][31], as one of the most important MIMs, have been deeply investigated because of their excellent properties and convenient synthesis. By introducing various
Synthesis and supramolecular self-assembly of glutamic acid-based squaramides
Beilstein J. Org. Chem. 2018, 14, 2065–2073, doi:10.3762/bjoc.14.180
- derivative; organogel; self-assembly; squaramide; supramolecular gel; Introduction Since their discovery, squaramides have gained importance across different fields from chemistry to biomedicine due to their synthetic versatility and wide applicability [1]. These compounds, formed by two amine units
- crystal engineering [13][14][15][16][17]. Despite their isosteric relationship with ureas, which have become key synthons in supramolecular chemistry [18][19], there are only a few reports on the formation of self-assembled supramolecular gels using squaramide derivatives [20][21][22][23]. Along this line
- , supramolecular or physical gels have received great attention during the last decade [24][25] due to their unique architectures and potential applications in many areas such as biomedicine (mainly hydrogels), health care and catalysis, among others [26][27][28][29]. In contrast to chemical gels [30], physical
Coordination-driven self-assembly vs dynamic covalent chemistry: versatile methods for the synthesis of molecular metallarectangles
Beilstein J. Org. Chem. 2018, 14, 2027–2034, doi:10.3762/bjoc.14.178
- , Ministry of Education, Anhui Normal University, Wuhu 241002, China 10.3762/bjoc.14.178 Abstract Supramolecular coordination assemblies have a range of potential applications in chemical and biological sciences. Herein, simple modular methods for the synthesis of metallarectangles are described. The
- self-assembly; dynamic covalent chemistry; half-sandwich rhodium complex; metallarectangles; one-pot reaction; supramolecular chemistry; Introduction Over the past two decades, supramolecular structures with organometallic half-sandwich fragments have attracted much attention, including
- coordination-driven self-assembly has been proven to be a powerful tool to construct supramolecular architectures with controlled shapes and sizes [18][19][20][21][22][23][24][25][26][27][28][29][30]. Using this strategy, a host of exciting supramolecular structures have been constructed by using two
A self-assembled photoresponsive gel consisting of chiral nanofibers
Beilstein J. Org. Chem. 2018, 14, 1994–2001, doi:10.3762/bjoc.14.174
- absorption spectroscopy, circular dichroism, scanning electron microscopy and rheological techniques. This work provides a new method for facile synthesis of chiro-optical gels. Keywords: chirality; nanostructure; organogel; photoresponse; self-assembly; Introduction Supramolecular gels [1][2] immobilized
- ], and chemosensing [13][14]. Among the supramolecular gels, the low-molecular-weight gels (LMWGs) [15][16] are those that self-assemble into gels in organic solvents with molecular weights of <2000 Da. The weak noncovalent intermolecular interactions between LMWGs make them more sensitive to external
- formation of supramolecular structure. To investigate the potential photoresponsiveness of compound 3, the UV–vis absorption spectrum was measured to trace photochemical and photophysical properties of the solution of compound 3 (1.0 × 10−5 M in chloroform). As shown in Figure 2, the azobenzene trans-isomer
Synthesis of new p-tert-butylcalix[4]arene-based polyammonium triazolyl amphiphiles and their binding with nucleoside phosphates
Beilstein J. Org. Chem. 2018, 14, 1980–1993, doi:10.3762/bjoc.14.173
- concentration. Second, the dye should not be fully absorbed in the hydrophobic domain of an aggregate to be easily released into solution after any changes that occur with the molecule/aggregate. In this context premicellar aggregates are good candidates to design supramolecular systems for recognition and
- complex formation was calculated as a difference between free energy of calix[4]arene + ADP/ATP complex and isolated calix[4]arene and ADP/ATP dianion. The complex structures corresponding to the minimum energy as well as supramolecular binding motif of ADP and ATP are presented in Figure 4. As can be
- seen ADP more effectively embeds into the molecular cleft formed by two ammonium moieties due to a good host–guest geometric size and/or shape complementarity (Figure 4a and c). The three phosphate groups of ATP have a larger size and cannot realize a similar supramolecular motif in the complex. For
Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril
Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171
- -dipyrromethene (BODIPY) dyes as a new class of fluorophores for the design of reporter dyes for supramolecular host–guest complex formation with cucurbit[7]uril (CB7). The BODIPYs contain a protonatable aniline nitrogen in the meso-position of the BODIPY chromophore, which was functionalized with known binding
- transfer; supramolecular chemistry; Introduction Cucurbit[n]urils (CBn, n = 5–8, 10, and 14) are a class of macrocyclic host molecules which are water soluble, nontoxic, and are able to bind a large variety of neutral and cationic guests in their inner cavity with high affinity [1][2][3][4]. This unique
- −1 for the cyclohexylmethylammonium cation, 5.3 × 103 M−1 for the anilinium cation and 1.4 × 105 M−1 for the benzylammonium cation in the 10 mM citrate buffer in 30% (v/v) ACN in water. As another advantage over previously established supramolecular reporter dyes, the absorption maximum of the
Synthesis and characterization of π–extended “earring” subporphyrins
Beilstein J. Org. Chem. 2018, 14, 1956–1960, doi:10.3762/bjoc.14.170
- 3Pd is further red-shifted and more intense. Keywords: aromaticity; earring subporphyrin; π-extended; supramolecular chemistry; Findings Since its first synthesis in 2006 [1][2], subporphyrin, the lowest homolog of porphyrins, has received considerable attention [3][4][5][6][7][8] due to its 14π
Recent advances in materials for organic light emitting diodes
Beilstein J. Org. Chem. 2018, 14, 1944–1945, doi:10.3762/bjoc.14.168
- obtained his Ph.D. from McGill University in 2003. He then completed two postdoctoral fellowships, one in supramolecular chemistry at the Organic Chemistry Institute, University of Zurich and the other in inorganic materials chemistry at Princeton University. After beginning his career in Canada, he moved
An amphiphilic pseudo[1]catenane: neutral guest-induced clouding point change
Beilstein J. Org. Chem. 2018, 14, 1937–1943, doi:10.3762/bjoc.14.167
- upon addition of a neutral guest, 1,4-dicyanobutane. The supramolecular structural change contributed to a significant increase in the hydrophobic ratio of the molecule, which induced insolubilization of 3 in aqueous media at 20 °C and a decrease of the clouding point temperature. Neutral guest
- -responsive LCST changes are very rare, while there have been some examples of LCST control using ionic chemical stimuli [5][6]. Results and Discussion Supramolecular structure and clouding point of bicyclic compound 3 The bicyclic compound 3 was prepared using a copper(I)-catalyzed alkyne–azide cycloaddition
- supramolecular structure of 3 by 1H NMR spectroscopy. In CDCl3, the signals from the alkyl chain of 3 (blue peaks, a–e, Figure 2) were observed upfield compared with the ones of the model compound 4 (Figure 2a). This is due to an aromatic shielding by the pillar[5]arene cavity, indicating that 3 mainly formed a
Asymmetric Michael addition reactions catalyzed by calix[4]thiourea cyclohexanediamine derivatives
Beilstein J. Org. Chem. 2018, 14, 1901–1907, doi:10.3762/bjoc.14.164
- and yields of the Michael reactions. Supramolecular catalysis has drawn tremendous interest in the past few years [15][16][17][18][19][20][21][22][23]. In this context, calixarenes are ideal supramolecular macrocyclic scaffolds for the design of molecular receptors and organocatalysts due to their
- nitrostyrene 7a lacking substituents has minimal steric hindrance and tends to bind with the calixarene cavity by supramolecular host–guest interactions which could further improve the enantioselectivity. In addition, electronic effects of the substituents on the aromatic ring showed a significant influence on
- supramolecular host–guest interaction with the calixarene to form a stable transition state A. Then, another hydrogen bond is formed between the nitrogen atom of the tertiary amine group in A and acetylacetone in its enol form, leading to the formation of a ternary complex B. Finally, nucleophilic attack of
A hemicryptophane with a triple-stranded helical structure
Beilstein J. Org. Chem. 2018, 14, 1885–1889, doi:10.3762/bjoc.14.162
- part). They display recognition properties toward neurotransmitters and carbohydrates, and can act as molecular switches and supramolecular catalysts [11]. Their C3 symmetry makes them promising candidates to build molecular cages displaying a triple helical arrangement of the linkers. Furthermore, we
Strong binding and fluorescence sensing of bisphosphonates by guanidinium-modified calix[5]arene
Beilstein J. Org. Chem. 2018, 14, 1840–1845, doi:10.3762/bjoc.14.157
- in view of low cost, ease of use and high sensitivity of optical sensing modalities, but remains a challenge since BPs are considered as unlabeled analytes. With the development of the host–guest concept in supramolecular chemistry, the indicator displacement assay (IDA), pioneered by Prof. Anslyn
Recent advances in hypervalent iodine(III)-catalyzed functionalization of alkenes
Beilstein J. Org. Chem. 2018, 14, 1813–1825, doi:10.3762/bjoc.14.154
- asymmetric induction. The NH group engages hydrogen bonding with the acetoxy groups located at an iodine(III) center to form two nine-membered rings, which were confirmed by the crystal structure of the iodine(III) reagent 16 [53]. The hydrogen bonding effect is crucial to a supramolecular helical chiral
Host–guest complexes of conformationally flexible C-hexyl-2-bromoresorcinarene and aromatic N-oxides: solid-state, solution and computational studies
Beilstein J. Org. Chem. 2018, 14, 1723–1733, doi:10.3762/bjoc.14.146
- ], coordination chemistry [12][13], biological systems [14] and especially for host–guest (H–G) chemistry [15]. Resorcinarenes can be modified at either the upper rim 2-position, lower rim, or both, to deliver supramolecular structures with the required structure for a given function [16][17][18]. We have shown
- various upper-rim substituents, differing lower-rim alkyl chain length, specific guests, and selective solvents, have made resorcinarenes an attractive platform for H–G applications. Through careful rational supramolecular design via self-assembly processes, our lab and others have combined simple 1:1 H–G
- building blocks into dimers [29][30][31], hexamers [32] or supramolecular chains (1D), sheets (2D), or lattice (3D) networks [15]. The detailed analysis of the molecular level interactions of these systems also has enabled our research to design constructs with specific individual molecular and electronic
Design, synthesis and structure of novel G-2 melamine-based dendrimers incorporating 4-(n-octyloxy)aniline as a peripheral unit
Beilstein J. Org. Chem. 2018, 14, 1704–1722, doi:10.3762/bjoc.14.145
- block copolymers and G-0 monomeric or dimeric dendritic liquid crystals with photochromic azobenzene mesogens. The present ab initio study explores a previously unknown use of 4-(n-octyloxy)aniline in the synthesis, structure and supramolecular behaviour of new dendritic melamines. Results: Starting
- (ethynyl)-s-triazine and various icosanyloxyphenylazides) with liquid crystalline and luminescent properties [22]. On the other hand, mesogenic supramolecular perylene bisimide assemblies with a number of 2-amino-4,6-bis[(4-alkoxy)phenylamino]-s-triazines [23], amphiphilic azobenzene-containing linear
Synthesis of diamido-bridged bis-pillar[5]arenes and tris-pillar[5]arenes for construction of unique [1]rotaxanes and bis-[1]rotaxanes
Beilstein J. Org. Chem. 2018, 14, 1660–1667, doi:10.3762/bjoc.14.142
- ]rotaxane and [1]rotaxane are one of particular supramolecular assembly system and are considered as an important building block in the construction of diverse MIMs [5][6][7][8][9][10]. [1]Rotaxane has a macrocyclic wheel component connected with a self-locked chain axle, and a bulky stopper at the terminal
- explosive development on the construction of various supramolecular devices and diverse responsive materials has been reported by using diverse functionalized pillararenes [33][34][35]. Due to easily preparation and suitable cavity, functionalized pillar[5]arenes were widely used as wheel component for
- feature was obtained in the five single crystals. That is, the longer chain of methyl (ethyl) oxyalkoxybenzoate not only does not inserted in the cavity of the pillar[5]arene to form the pseudo[1]rotaxane, but also does not thread to the cavity of the neighbouring pillar[5]arene to form the supramolecular
The phenyl vinyl ether–methanol complex: a model system for quantum chemistry benchmarking
Beilstein J. Org. Chem. 2018, 14, 1642–1654, doi:10.3762/bjoc.14.140
- contact is reminiscent of stabilization effects observed in coupled diamondoids [69] or supramolecular complexes [70], where such interactions can be found in large numbers. Electronic ground state spectra FTIR spectroscopy The results of an FTIR exploration of the conformational diversity of this system
A conformationally adaptive macrocycle: conformational complexity and host–guest chemistry of zorb[4]arene
Beilstein J. Org. Chem. 2018, 14, 1570–1577, doi:10.3762/bjoc.14.134
- binding behavior of ZB4 and lays the basis for the construction of stimuli-responsive materials with ZB4 as a major component. Keywords: conformations; host–guest chemistry; macrocycles; supramolecular chemistry; zorb[4]arene; Introduction Macrocyclic receptors are the principal workhorses used in
- supramolecular chemistry [1]. A myriad of synthetic macrocycles have sprouted during the past decade, greatly enriching the arsenal of supramolecular chemists [2][3][4][5][6][7][8][9][10][11]. The majority of artificial macrocycles are featured with rigid backbones as it is widely accepted that preorganization
Hyper-reticulated calixarene polymers: a new example of entirely synthetic nanosponge materials
Beilstein J. Org. Chem. 2018, 14, 1498–1507, doi:10.3762/bjoc.14.127
- preliminary tests to assess their supramolecular absorption abilities towards a set of suitable organic guests, selected as pollutant models. The synthesis was accomplished by means of a CuAAC reaction between a tetrakis(propargyloxy)calix[4]arene and an alkyl diazide. The formation of the polymeric network
- ; solid-state NMR; Introduction Nanosponges (NSs) [1][2][3] constitute an emerging area of both materials chemistry and supramolecular chemistry due to their peculiar properties, which have been object of an increasing interest during the last years. These materials are constituted by hyper-reticulated
- polymers obtained joining supramolecular host units, as the monomers, by means of a suitable reticulating agent. Up to date, the examples by far most studied are constituted by cyclodextrin-based nanosponges (CyNSs) [4][5], which can be synthesized by reacting native β-cyclodextrin with double
Recent advances in phosphorescent platinum complexes for organic light-emitting diodes
Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124
Recent applications of chiral calixarenes in asymmetric catalysis
Beilstein J. Org. Chem. 2018, 14, 1389–1412, doi:10.3762/bjoc.14.117
- calixarene; organocatalyst; supramolecular catalyst; Introduction The catalysis of organic reactions by macrocyclic host compounds is a longstanding proposed application of supramolecular chemistry and utilizes the use of noncovalent interactions in catalytic systems to achieve higher reaction rates, more
- asymmetric catalysis has received considerable interest and witnessed significant progress in recent years [2][3][4]. Calixarenes are considered as the third generation of supramolecular hosts after cyclodextrins and crown ethers [5][6]. Due to their easy preparation and readily modification at either the
A three-armed cryptand with triazine and pyridine units: synthesis, structure and complexation with polycyclic aromatic compounds
Beilstein J. Org. Chem. 2018, 14, 1370–1377, doi:10.3762/bjoc.14.115
- titration; 1,3,5-triazine; Introduction Cryptands with C3-symmetric aromatic reference groups are exciting targets, on the one hand due to the challenges encountered in their synthesis and on the other due to their ability (macrobicyclic effect [1]) to form supramolecular assemblies with cations, anions or
- neutral guests, e.g., aromatic molecules [2][3][4][5][6]. The supramolecular architectures involving cryptands (including metallomacrocycles) and aromatic guests are targeted for investigations of aromatic–aromatic contacts [7][8] and for various applications in molecular electronics [9][10]. The recently
- reported cage-box [11] is able to complex a plethora of aromatic compounds (e.g., anthracene, pyrene, perylene), while in the cases of several metallo-based cryptands the formation of layered host–guest supramolecular structures (with many guests in the cavity of the host) were reported [12][13][14][15
A selective removal of the secondary hydroxy group from ortho-dithioacetal-substituted diarylmethanols
Beilstein J. Org. Chem. 2018, 14, 1229–1237, doi:10.3762/bjoc.14.105
- been used in the treatment of overactive bladder, external genital warts and osteoporosis (Figure 1). The diarylmethyl motif also plays a pivotal role in supramolecular architectures of calixarenes [13] and orthocyclophanes [14]. A special, ortho-carbonyl-substituted diarylmethyl scaffold is present in
Local energy decomposition analysis of hydrogen-bonded dimers within a domain-based pair natural orbital coupled cluster study
Beilstein J. Org. Chem. 2018, 14, 919–929, doi:10.3762/bjoc.14.79
- publications [23][24][25][26][27][28][29][30][31][32][33]. We thus only recall here the main features of this technique. Within a supramolecular approach, the energy of a molecular adduct XY relative to the total energies of noninteracting fragments X and Y, i.e, dimerization energy (ΔE), can be written as
- compare with the ones from energy decomposition schemes based on a supramolecular approach, e.g., the LED. Despite these differences, it is still interesting to compare whether both approaches lead to a similar partitioning of dispersion and electrostatics, in order to draw connections between different
Recent advances in synthetic approaches for medicinal chemistry of C-nucleosides
Beilstein J. Org. Chem. 2018, 14, 772–785, doi:10.3762/bjoc.14.65
- and supramolecular complexes [10][11][12][13][14][15][16][17][18][19][20][21][22]. Nucleic acids are composed of a monomeric nucleoside unit that features an aromatic nitrogenous moiety (a nucleobase) connected to a pentose sugar, which in turn is attached to a phosphate group (Figure 1) [7]. The
- stability, ii) altered hydrogen bonding motifs, and iii) altered molecular recognition properties [25][29][37][58]. Because of these changes, C-nucleosides have been useful in the study of RNA and DNA processing enzymes, as well as drug design efforts and novel supramolecular structures [12][29][59
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