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We recently reported photoresponsive, dissipative, and dynamic covalent macrocycles that use visible-light photoswitching. Several other exciting contributions involving the use of metal–organic and metal-free supramolecular assemblies have been published back-to-back; here, we have a closer look at these contributions, together with an in-depth insight into our macrocyclic system. 1 Introduction 2 Photoswitchable Dissipative Supramolecular Systems 3 Photoresponsive Dynamic Covalent Imine Macrocycles 4 Conclusion [ABSTRACT FROM AUTHOR]

Cyclophanes are an admirable class of macrocyclic and cage compounds that often display unusual properties due to their high strain and unusual conformations. However, the exploration of new, complex cyclophanes has been encumbered by syntheses that can be low yielding, require harsh reaction conditions, and arduous purification steps. Herein, we discuss our work using metalloid-directed self-assembly and dynamic covalent chemistry to form cryptands. These were then subjected to mild conditions to produce discrete disulfide, thioether and hydrocarbon macrocycles in high yields. 'Design of Experiments' was then used to selectively synthesize targeted macrocycles from complex mixtures. 1 Introduction 2 Cryptands to Cyclophanes 3 Functionalizable Macrocycles 4 'Design of Experiments' Targeted Synthesis 5 Conclusions and Outlook [ABSTRACT FROM AUTHOR]

To expand the toolbox of dynamic covalent and systems chemistry, we investigated the acid-catalyzed exchange reaction of trithioorthoesters with thiols. We found that trithioorthoester exchange occurs readily in various solvents in the presence of stoichiometric amounts of strong Brønsted acids or catalytic amounts of certain Lewis acids. The scope of the exchange reaction was explored with various substrates, and conditions were identified that permit clean metathesis reactions between two different trithioorthoesters. One distinct advantage of S , S , S -orthoester exchange over O , O , O -orthoester exchange is that the exchange reaction can kinetically outcompete hydrolysis, thereby making the process less sensitive to residual moisture. We expect that the relatively high stability of the products might be beneficial in future supramolecular receptors or porous materials. [ABSTRACT FROM AUTHOR]

There is unabated interest in developing new strategies for the control of atropisomers despite the rich history of atropisomerism. We recently introduced dynamic covalent reactions (DCRs) within biphenyl skeletons for the incorporation and chirality recognition of multiple classes of mononucleophiles. To expand the scope of this strategy, the sulfonamide unit was switched from an endocyclic to an exocyclic position, and the influence of the resulting DCRs on chiral induction was investigated. The intramolecular equilibrium between the open aldehyde and its cyclic hemiaminal favored the ring form, and excellent chirality transfer from the hemiaminal stereocenter to the helical twist of the biphenyl was revealed. The modulation of unique dual reactivity then allowed the realization of DCRs of a diverse set of amines and alcohols. The degree of chirality induction was further explored by employing chiral substrates, affording significant circular dichroism signals. [ABSTRACT FROM AUTHOR]

Dynamic covalent self-assembly of small and rigid precursors into cage-type architectures can serve as a powerful strategy for the formation of molecular porous units. In order to enhance the functionality of suchlike nanostructures, formation of complex multicomponent assemblies with high spatial precision, and on-demand control of both reversible assembly and disassembly is highly desirable. Here we highlight some of our most recent achievements on the size-specific synthesis and self-sorting properties within a series of covalent organic cage compounds and the stimuli-responsive assembly of supramolecular cages assembled by boron-nitrogen dative bonds. 1 Introduction 2 Self-Sorting of Covalent Organic Cages 3 Stimuli-Responsive Cages 4 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Cryptands can be seen as the smallest three-dimensional molecular cages still capable of accommodating (ionic) guests. We have recently realized the first dynamic covalent self-assembly of a monometallic cryptate, whose template synthesis and unique structure crucially rest on orthoester bridgeheads [Nat. Commun. 2015, 6, 7129]. In this Synpacts article, I discuss selected aspects that led to this discovery and I attempt to put the study into the context of recent trends in the selfassembly of larger molecular cages. [ABSTRACT FROM AUTHOR]

Subcomponent self-assembly allows for the construction of complex architectures from simple building blocks via the simultaneous, reversible formation of covalent and coordinative bonds. Complex structures may be rapidly built by taking advantage of the different and complementary selectivities of covalent and coordinative bond-forming reactions. Because both kinds of bonds are formed under thermodynamic control, a wide variety of rearrangement reactions are possible involving substitution at both intraligand and metal-ligand bonds. Understanding the selectivities that underlie these reactions also allows one to pick out specific products from among diverse dynamic combinatorial libraries of interconverting structures. 1 Introduction 2 Initial Work 2.1 Aqueous Copper(I)-Templated Subcomponent Self-[nl]Assembly 3 Construction 3.1 Dicopper and Tricopper Helicates 3.2 Tetracopper(I) Grid 3.3 Catenates and Macrocycles 4 Rearrangements 4.1 Cascade Reaction 4.2 Electronic Effects 5 Sorting 5.1 Sorting Ligand Structures with Copper(I) 5.2 Cooperative Selection by Iron and Copper 5.3 Sorting within a Structure 6 Systems Chemistry 6.1 Deterministic Self-Sorting Systems of Subcomponents 6.2 Interplay between Three Dynamic Equilibria 7 Chiral Information Transfer 7.1 Chirality Transfer from Carbon to Copper(I) 7.2 Chiral Resolution during Crystallization 8 Boron-Templated Self-Assembly 8.1 Mononuclear Boron-Templated Structures 8.2 More-Complex Structures 8.3 Subcomponent Substitution Reactions within Imino�boronate Ester Systems 9 Conclusions [ABSTRACT FROM AUTHOR]