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Cucurbit[n]uril supramolecular chemistry has developed rapidly since 2001 when different cucurbit[n]uril homologues (Q[n]) were successfully separated in pure form. The combination of Q[n] cavity size and various types of external stimuli has given birth to numerous types of Q[n]-based mechanically interlocked molecules (MIMs), including (pseudo)rotaxanes, catenanes, dendrimers and poly(pseudo)rotaxanes. In this review article, the important advances in the field of Q[n]-based MIMs over the past two decades are highlighted. This review also describes examples of heterowheel (pseudo)rotaxanes and poly(pseudo)rotaxanes involving Q[n]s, and reflects on the opportunities and challenges of constructing Q[n]-based stimuli-responsive MIMs. [ABSTRACT FROM AUTHOR]

The nature of mechanically interlocked molecules (MIMs) has continued to encourage researchers to design and construct a variety of high-performance materials. Introducing mechanically interlocked structures into polymers has led to novel polymeric materials, called mechanically interlocked polymers (MIPs). Rotaxane-based MIPs are an important class, where the mechanically interlocked characteristic retains a high degree of structural freedom and mobility of their components, such as the rotation and sliding motions of rotaxane units. Therefore, these MIP materials are known to possess a unique set of properties, including mechanical robustness, adaptability and responsiveness, which endow them with potential applications in many emerging fields, such as protective materials, intelligent actuators, and mechanisorption. In this review, we outline the synthetic strategies, structure-property relationships, and application explorations of various polyrotaxanes, including linear polyrotaxanes, polyrotaxane networks, and rotaxane dendrimers. [ABSTRACT FROM AUTHOR]

We present the successful construction of a new family of organometallic rotaxane-terminated dendrimers using neutral platinum–acetylides as the main scaffold. The fourth generation dendrimer has 24 rotaxane moieties on the surface termini in a monodisperse manner. [ABSTRACT FROM AUTHOR]

The development of multicomponent (supramolecular) systems that can perform predetermined functions under external control -- i.e., molecular devices -- is a challenging task in chemistry and a fascinating objective in the frame of a bottom-up approach to nanostructures. In this context light signals can be conveniently used both for supplying energy to the system and for probing its states and transformations. The aim of this tutorial review is to recall a few basic aspects of light-induced processes that can be used to "write" and "read" onto molecular and supramolecular systems. These principles are illustrated through some examples of artificial molecular devices and machines taken from our work, which provide a flavour of current research. They are molecular and supramolecular systems that operate and/or perform valuable functions by exploiting photoinduced energy- or electron-transfer processes, photoisomerization reactions, or photoinduced proton transfer. The choice of these examples was based on both their intrinsic importance for the referred topic and their educational value. In the last section of the review potential applications, limitations and future directions of the research in the field of artificial molecular devices and machines are also discussed. [ABSTRACT FROM AUTHOR]

A series of dendritic ammonium salts have been designed and synthesized. Subsequently, they were used to construct the corresponding [2]rotaxanes by a template-directed clipping approach. Unusually, two unsymmetrical dendritic [2]rotaxanes containing fluorophore (pyrene units) were also obtained; their optical properties, such as UV/vis absorption and fluorescence, were measured. The results indicate that these two rotaxanes possess stronger intermolecular interaction in the solid state than in solution. As a result, solutions of high concentration readily formed the excimer. These special rotaxanes might be applied in dynamic fluorescence-reponsive materials, and the rotaxane structure will also be used as a strategy to adjust the aggregated behaviors of fluorescent molecules. [ABSTRACT FROM AUTHOR]

Mechanically bonded macromolecules constitute a class of challenging synthetic targets in polymer science. The controllable intramolecular motions of mechanical bonds, in combination with the processability and useful physical and mechanical properties of macromolecules, ultimately ensure their potential for applications in materials science, nanotechnology and medicine. This tutorial reviewdescribes the syntheses and properties of a library of diverse mechanically bonded macromolecules, which covers (i) main-chain, side-chain, bridged, and pendant oligo/polycatenanes, (ii) main-chain oligo/polyrotaxanes, (iii) poly[c2]daisy chains, and finally (iv) mechanically interlocked dendrimers. A variety of highly efficient synthetic protocols—including template-directed assembly, step-growth polymerisation, quantitative conjugation, etc.—were employed in the construction of these mechanically interlocked architectures. Some of these structures, i.e., side-chain polycatenanes and poly[c2]daisy chains, undergo controllable molecular switching in a manner similar to their small molecular counterparts. The challenges posed by the syntheses of polycatenanes and polyrotaxanes with high molecular weights are contemplated. [ABSTRACT FROM AUTHOR]

A squaraine rotaxane scaffold with four alkyne groups is readily converted into a range of dendritic architectures using high-yielding copper-catalyzed alkyne azide cycloaddition (CuAAC) chemistry. A convergent synthesis approach is more efficient than a divergent pathway. Dendritic squaraine rotaxanes with peripheral amine groups can be further functionalized to produce multivalent deep-red fluorescent derivatives that exhibit high brightness and outstanding chemical stability in biological solution. The surface groups on these functionalized fluorescent dendrimers include guanidinium, mannose, and phosphatidylcholine. [ABSTRACT FROM AUTHOR]

Abstract: The electron and energy accepting properties of fullerene C60 can be readily exploited upon the selection of suitable donating species to construct supramolecular assemblies which display photoinduced electron and/or energy transfer processes. In this account we focus on the use of transition metal complexes in the role of the electron/energy donor, in particular we discuss the photophysical properties of some fullerene hybrid systems containing tris(2,2′-bipyridine)ruthenium(II), (2,2′-bipyridine)rhenium(I) or bis(1,10-phenanthroline)copper(I) subunits that we have investigated over the years. In fullerene hybrid dyads with Ru(II) and Re(I) complexed moieties, electron transfer is observed at room temperature in both cases, while it is blocked at 77 K in the former case. For multicomponent arrays (rotaxane, dendrimers, helicates) with Cu(I)-bisphenanthroline moieties, quenching by electron/energy transfer of the MLCT excited states of the metal complexed moiety is always found. When excitation is addressed to the carbon cage, photoinduced processes occurs when methanofullerenes are involved, but not with bismethanofullerenes. To cite this article: J.N. Clifford et al., C. R. Chimie (9) 2006 . [Copyright &y& Elsevier]

Supramolecular (multi-component) systems can perform complex functions which result from the cooperation of actions performed by suitably selected molecular components. Looking at supramolecular systems, from the viewpoint of the functions, shows that the concept of macroscopic device can be extended to molecular level. Nature exploits very complex molecular-level devices to substain life, and, in the last twenty years, the development of supramolecular chemistry has allowed the construction of simple molecular-level devices, that are of interest not only for basic research, but also for the growth of nanoscience and nanotechnology.Molecular-level devices operate via electronic and/or nuclear rearrangements, and like macroscopic devices, they need energy to operate and signals to communicate with the operator. Electrochemistry can provide the answer to this dual requirement, since electrons/holes, besides supplying the energy needed to make a devices work, can also be useful to “read” the state of the system and thus to control and monitor the operation of the device. In this article, some examples of molecular-level devices investigated in our laboratory will be reviewed. [Copyright &y& Elsevier]

Type III-B first generation [3]rotaxane and second generation [4]rotaxane dendrimers have been synthesized via (1) a modified copper-catalyzed alkyne–azide cycloaddition (CuAAC), (2) Glaser–Hay's acetylenic oxidative homo-coupling, and (3) amide formation. The dendron does not reveal obvious cytotoxicities in L929 fibroblast cells. The rotaxane dendrimers can capture ammonia and are switchable both in solution and on surfaces. [ABSTRACT FROM AUTHOR]

The article discusses template-directed dynamic synthesis of mechanically interlocked dendrimers. Recently, the versatility of dynamic covalent chemistry (DCC) has been demonstrated in the multicomponent construction of complex mechanically interlocked compounds, such as molecular bundles and nanoscale Borromean rings, as well as in the highly efficient template-directed synthesis of (2) rotaxanes. It has been found that by taking advantage of dynamic covalent chemistry, dendrons from generation zero to two can be self-assembled in near quantitative yields into, first of all, kinetically labile and, then, kinetically stable mechanically interlocked dendrimers.

Review: 'classic' and recent results concerning their chemistry, applications and crysal structure; 128 refs. [ABSTRACT FROM AUTHOR]

Review: 127 refs. [ABSTRACT FROM AUTHOR]

Review: [73 refs. [ABSTRACT FROM AUTHOR]

An abstract of the article "Host-Guest Properties of Pillar(n)arenes" by T. Ogoshi and T.-A. Yamagishi is presented.

Review: [synthesis and properties of pillar[n]arene based supramolecular complexes]. [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 "Synthesis of Pillar[n]arenes" 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: 98 refs. [ABSTRACT FROM AUTHOR]

Review: 39 refs. [ABSTRACT FROM AUTHOR]

Review: [54 refs. [ABSTRACT FROM AUTHOR]

Review: recent research advances in the synthesis, characterization, and catalytic proerties; 90 refs. [ABSTRACT FROM AUTHOR]

Review: 291 refs. [ABSTRACT FROM AUTHOR]

Review: efforts in the development of a highly efficient copper-free click reaction for the synthesis of oligo- and polyrotaxanes with potential commercial value; 50 refs. [ABSTRACT FROM AUTHOR]

Review: 38 refs. [ABSTRACT FROM AUTHOR]

The article presents reference of the article "Multivalent Glycocalixarenes: Synthesis and Molecular Recognition" and others, published in the "RSC Polymer Chemistry Series" in 2016.

The article offers information about kinetic resolution of a racemic paracyclophane through transfer hydrogenation.

Review: 132 refs. [ABSTRACT FROM AUTHOR]

Review: 109 refs. [ABSTRACT FROM AUTHOR]

Review: [synthetic routes and selected applications in imaging, drug developement and bioapplications; 79 refs. [ABSTRACT FROM AUTHOR]

Review: 101 refs. [ABSTRACT FROM AUTHOR]

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Review: 267 refs. [ABSTRACT FROM AUTHOR]

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Review: 61 refs. [ABSTRACT FROM AUTHOR]

The article offers information on a study related to an article regarding synthesis of optically active conjugated compounds on planar chiral paracyclophane by M. Gon and others, published in the journal "Chemistry - A European Journal " in 2015.

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: [266 refs. [ABSTRACT FROM AUTHOR]

This section cites the study "Synthetic Approaches to Cyclophanes via Claisen Rearrangement and Ring-Closing Metathesis as Key Steps," by S. Kotha and colleagues.

A new method to synthesize para-cyclophanes and longithorone C frameworks is reported involving alkylation, ceric ammonium nitrate oxidation and ring-closing metathesis as key steps. [ABSTRACT FROM AUTHOR]

Several catenanes are synthesized by olefin metathesis dimerization. [ABSTRACT FROM AUTHOR]

Synthesis of tetrathia[8]circulenes is achieved by sequential C-H borylation and annulation from cyclic tetrathiophene. [ABSTRACT FROM AUTHOR]

Using in-situ prepared LiNK reagent, methylarenes are sequentially converted into mono- and bis-trimethylsilylated derivatives. [ABSTRACT FROM AUTHOR]

Review: 66 refs. [ABSTRACT FROM AUTHOR]

It is found that the configuration of the double bond formed during the RCM depends on the order of the synthetic route. The Fischer indolization followed by RCM lead to the cis-isomer, whereas the RCM followed by Fischer indolization lead to the trans-isomer. [ABSTRACT FROM AUTHOR]

Review: 143 refs. [ABSTRACT FROM AUTHOR]

Review: 39 refs. [ABSTRACT FROM AUTHOR]