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The article presents information about calix arenes substituted by urea groups at the wide rim. It is now well established, that calix arenes of type 1 substituted by urea groups at the wide rim form hydrogen-bonded dimeric capsules in apolar solvents. If these functional groups are preorganized in heterodimers, which are exclusively formed with tetratosyl ureas as template, multimacrocyclic compounds are available in excellent yield from which the newly formed macrocycles can be detached in a final step. The structure of the tetra rotaxanes was unambiguously confirmed not only by the nuclear magnetic resonance-spectroscopic changes, but also by ESI-MS or MALDI-TOF-MS showing the expected molecular peaks.

Macrocyclic arenes including calixarenes, resorcinarenes, cyclotriveratrylene, pillararenes and so on have emerged as highly attractive synthetic macrocyclic hosts due to their unique structures, facile functionalization, and broad range of applications. In recent years, there has been growing interest in the development of novel macrocyclic arenes composed of various aromatic building blocks bridged by methylene groups, which have found applications in various research areas. Consequently, the development of novel macrocyclic arenes has become a frontier and hot topic in supramolecular and macrocyclic chemistry. In this review, we feature the recent advances in the synthesis and applications of novel macrocyclic arenes that have emerged in the last decade. The general synthetic strategies employed for these macrocyclic arenes are systematically summarized, and their wide applications in molecular recognition and assemblies, molecular machines, biomedical science and functional materials are highlighted. [ABSTRACT FROM AUTHOR]

Heteroditopic calix[6]arenes are extensively exploited as synthetic receptors and as molecular components of supramolecular threaded and interlocked structures. We describe the synthesis of two novel calix[6]arene macrocycles, the upper rim of which is functionalized with either two or three phenylthioureido groups. These moieties are excellent hydrogen‐bond donors and largely affect the conformation of the macrocycle, both in solution and in the solid state. Alternate conformers are observed in solution, and they give rise to supramolecular chains in the solid state. Moreover, and because of this conformational freedom, also the recognition properties toward the formation of pseudorotaxanes with bipyridinium‐based axles are strongly affected. The number of phenylthioureido units of the macrocyclic host and the nature of the counterions of the bipyridinium guest determine the stability of the complexes. NMR, UV‐Vis and electrochemical measurements revealed that very stable 1 : 1 inclusion complexes are formed between the triphenylthioureido calix[6]arene and a bipyridinium guest with tosylate counterions, whereas no complex is observed between the diphenylthioureido macrocycle and a hexafluorophosphate bipyridinium salt. [ABSTRACT FROM AUTHOR]

A reference of an article "Assembled Structures of Pillar[n]arenes" by T. Ogoshi and T.A. Yamagishi which was published in the 2016 issue of periodical "Monographs in Supramolecular Chemistry" is presented.

The article presents chemical equations related to the article "Functionalization of Pillararenes" by T. Ogoshi and others, published in the "Monographs in Supramolecular Chemistry" in 2016.

The article presents chemical equations related to the article "Conformation and Planar Chirality of Pillar[n]arenes" by T. Ogoshi and others published in the "Monographs in Supramolecular Chemistry" in 2016.

Review: 101 refs. [ABSTRACT FROM AUTHOR]

Review: 267 refs. [ABSTRACT FROM AUTHOR]

The newly developed method for the synthesis of pillar[6]arenes involves the solid-state condensation of finely milled 1,4-dialkoxybenzene and paraformaldehyde by grinding in the presence of a catalytic amount of H2SO4. [ABSTRACT FROM AUTHOR]

Review: [69 refs. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Regioselective Synthesis of 1,2- and 1,3-Diaminothiacalix[4]arenes via Nucleophilic Aromatic Substitution and Their X-Ray Structures" by H. Katagiri and others, published in the "RSC Advances" in 2014.

Review: 192 refs. [ABSTRACT FROM AUTHOR]

Review: [preparation, structure in solution and in the solid state and complexation; 100 refs. [ABSTRACT FROM AUTHOR]

Review: [62 refs. [ABSTRACT FROM AUTHOR]

Review: 109 refs. [ABSTRACT FROM AUTHOR]

Review: 57 refs. [ABSTRACT FROM AUTHOR]

Review: 37 refs. [ABSTRACT FROM AUTHOR]

The simple tetraminocalix[4]arene 1, which contains weak H-bond-donor NH2 groups, is reported to be a highly efficient organocatalyst for the Vinylogous Mukaiyama Aldol Reaction (VMAR) of 2-(trimethylsilyloxy)furan 5 with α-ketoesters 6 a- l under 'on-water' conditions owing to the hydrophobic amplification of weak H-bond interactions. The catalytic efficiency of calixarene catalyst 1 was shown to be closely related to its recognition abilities towards the reactants 5 and 6 through a multipoint recognition model. The proposed model provided good explanations for the differences on the reaction rate acceleration and on the stereoselectivity observed with different substrates. [ABSTRACT FROM AUTHOR]

Tris-( N-phenylureido)-calix[6]arene derivatives are heteroditopic non-symmetric molecular hosts that can form pseudorotaxane complexes with 4,4′-bipyridinium-type guests. Owing to the unique structural features and recognition properties of the calix[6]arene wheel, these systems are of interest for the design and synthesis of novel molecular devices and machines. We envisaged that the incorporation of photoactive units in the calixarene skeleton could lead to the development of systems the working modes of which can be governed and monitored by means of light-activated processes. Here, we report on the synthesis, structural characterization, and spectroscopic, photophysical, and electrochemical investigation of two calix[6]arene wheels decorated with three naphthyl groups anchored to either the upper or lower rim of the phenylureido calixarene platform. We found that the naphthyl units interact mutually and with the calixarene skeleton in a different fashion in the two compounds, which thus exhibit a markedly distinct photophysical behavior. For both hosts, the inclusion of a 4,4 ′-bipyridinium guest activates energy- and/or electron-transfer processes that lead to non-trivial luminescence changes. [ABSTRACT FROM AUTHOR]

First time, new calixarene-based dendrimers, containing calix[4]arene as the core and different generations of Frechet-type poly(benzyl ether) dendrons as building blocks, which possess either Br-atoms or COOtBu groups at their surface, are synthesized and presented. [ABSTRACT FROM AUTHOR]

Pillar[5]arenes, as a new intriguing class of calixarene analogues, were functionalized with ten diglycolamide (DGA) arms on both sides (rims) of the pillar framework and evaluated for their extraction behaviour towards Am(III) and Eu(III). These novel extractants exhibit excellent separation and extraction efficiency, suggesting its significant potential for nuclear waste remediation. Laser induced fluorescence experiments disclosed strong complexation of the trivalent metal ions with the pillararene-DGA ligands. [ABSTRACT FROM AUTHOR]

Four cyclophane derivatives with triazole-phosphane moieties are synthesized and tested as ligands in Suzuki cross-coupling reactions with compound (V) giving the best results. [ABSTRACT FROM AUTHOR]

Review: 72 refs. [ABSTRACT FROM AUTHOR]

Macrocycles play a crucial role in supramolecular chemistry and the family of macrocyclic arenes represents one of the most important types of hosts. Among them, calixarenes, resorcinarenes and pillararenes are the most commonly encountered macrocyclic arenes, and they have received considerable attention. Boron-dipyrromethene (BODIPY) dyes are fascinating compounds with multiple functionalization sites and outstanding luminescence properties including high fluorescence quantum yields, large molar absorption coefficients and remarkable photo- and chemical stability. The combination of macrocyclic arenes and BODIPY dyes has been demonstrated to be an effective strategy to construct chemosensors for various guests and smart materials with tailored properties. Herein, we firstly summarize the recent advances made so far in macrocyclic arenes substituted with BODIPY. This review only focuses on the three macrocyclic arenes of calixarenes, resorcinarenes and pillararenes, as there are no other macrocyclic arenes substituted BODIPY units at the present time. Hopefully, this review will not only afford a guide and useful information for those who are interested in developing novel chemosensors and smart materials, but also inspire new opportunities in this field. [ABSTRACT FROM AUTHOR]