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Amine-linked (C−NH) porous organic cages (POCs) are preferred over the imine-linked (C=N) POCs owing to their enhanced chemical stability. In general, amine-linked cages, obtained by the reduction of corresponding imines, are not shape-persistent in the crystalline form. Moreover, they require multistep synthesis. Herein, a one-pot synthesis of four new amine-linked organic cages by the reaction of 1,3,5-triformylphloroglucinol (Tp) with different analogues of alkanediamine is reported. The POCs resulting from the odd diamine (having an odd number of −CH₂ groups) is conformationally eclipsed, while the POCs constructed from even diamines adopt a gauche conformation. This odd–even alternation in the conformation of POCs has been supported by computational calculations. The synthetic strategy hinges on the concept of Schiff base condensation reaction followed by keto–enol tautomerization. This mechanism is the key for the exceptional chemical stability of cages and facilitates their resistance towards acids and bases.

Stable cages: A one-pot synthesis of four amine-linked porous organic cages is reported. These cages are exceptionally stable to acids and bases, and their odd–even effect on conformation was studied.

Chiral fullerene–metal hybrids with complete control over the four stereogenic centers, including the absolute configuration of the metal atom, have been synthesized for the first time. The stereochemistry of the four chiral centers formed during [60]fullerene functionalization is the result of both the chiral catalysts employed and the diastereoselective addition of the metal complexes used (iridium, rhodium, or ruthenium). DFT calculations underpin the observed configurational stability at the metal center, which does not undergo an epimerization process.

Chirality at the metal: Fullerene hybrids with iridium-, rhodium-, or ruthenium-centered chirality were prepared by precise control of four newly formed stereogenic centers. The resulting complexes are configurationally stable and do not undergo an epimerization process.

Inspired by the swimming of natural microorganisms, synthetic micro-/nanomachines, which convert energy into movement, are able to mimic the function of these amazing natural systems and help humanity by completing environmental and biological tasks. While offering autonomous propulsion, conventional micro-/nanomachines usually rely on the decomposition of external chemical fuels (e.g., H₂O₂), which greatly hinders their applications in biologically relevant media. Recent developments have resulted in various micro-/nanomotors that can be powered by biocompatible fuels. Fuel-free synthetic micro-/nanomotors, which can move without external chemical fuels, represent another attractive solution for practical applications owing to their biocompatibility and sustainability. Here, recent developments on fuel-free micro-/nanomotors (powered by various external stimuli such as light, magnetic, electric, or ultrasonic fields) are summarized, ranging from fabrication to propulsion mechanisms. The applications of these fuel-free micro-/nanomotors are also discussed, including nanopatterning, targeted drug/gene delivery, cell manipulation, and precision nanosurgery. With continuous innovation, future autonomous, intelligent and multifunctional fuel-free micro-/nanomachines are expected to have a profound impact upon diverse biomedical applications, providing unlimited opportunities beyond one's imagination.

Fuel-free synthetic micro-/nanomachines powered by external stimuli are able to swim efficiently in biologically relevant environments. Tremendous progress made in the past decade to develop different synthesis strategies for designing and fabricating fuel-free micro-/nanomotors with different functionalities is reviewed. These artificial nanomachines can achieve predetermined tasks in biomedical applications.

An inherently chiral C₃-symmetric triaminotribenzotriquinacene was condensed in racemic and enantiomerically pure form with a bis(salicylaldehyde) to form [2+3] salicylimine cage compounds. Investigations on the chiral self-sorting revealed that while entropy favors narcissistic self-sorting in solution, selective social self-sorting can be achieved by exploiting the difference in solubility between the homochiral and heterochiral cages. Gas sorption measurements further showed that seemingly small structural differences can have a significant impact on the surface area of microporous covalent cage compounds.

Sorted out: An inherently chiral C₃-symmetric triaminotribenzotriquinacene was condensed in racemic and enantiomerically pure form with a bis(salicylaldehyde) to form [2+3] salicylimine cage compounds. Investigations revealed that entropy favors narcissistic self-sorting in solution, and selective social self-sorting can be achieved by exploiting the difference in solubility between the homochiral and heterochiral cages.

The huge interest towards fullerenes and carbon nanotubes in molecular materials and materials science is closely related to the intriguing properties of these carbon nanostructures such as their excellent electrical conductivity and remarkable chemical stability, among others. In this connection, organic photovoltaics (OPVs) is one of the research fields where these carbon allotropes have been extensively employed, mainly as electron-accepting materials. Among the electron-donating counterparts, phthalocyanines (Pcs) and subphthalocyanines (SubPcs) are some organic compounds largely used for this pourpose mainly due to their intense light-harvesting ability in the red and near infrared region of the solar spectrum, and rich and tuneable redox chemistry. In this review, we summarize some of the most recent and relevant achievements in the preparation of fullerene- and carbon nanotube-based OPVs containing Pcs and/or SubPcs, paying a special attention to the effect that i) the structural and electronic modifications of the Pc and SubPc derivatives, ii) the different type of OPV architecture, and iii) the preparation method, have on the performance of the OPV devices. A section of this review has been also devoted to the used of SubPcs as electron-accepting materials in fullerene-free PV cells highlighting the great potential of these class of materials for the preparation of efficient organic solar cells.

Phthalocyanines and subphthalocyanines are optimal partners for fullerenes and carbon nanotubes in molecular photovoltaics. The latest advances on the incorporation of phthalocyanine/fullerene and subphthalocyanine/fullerene couples in different solar cell architectures are described and discussed in detail. Some examples on the functionalization of carbon nanotubes with phthalocyanines and the evaluation of their photovoltaic capability are also reviewed.

The integration of dynamic covalent bonds into macrocycles has been a tremendously successful strategy for investigating noncovalent interactions and identifying effective host–guest pairs. While numerous studies have focused on the dynamic responses of macrocycles and larger cages to various guests, the corresponding constitutionally dynamic chemistry of cryptands remains unexplored. Reported here is that cryptands based on orthoester bridgeheads offer an elegant entry to experiments in which a metal ion selects its preferred host from a dynamic mixture of competing subcomponents. In such dynamic mixtures, the alkali metal ions Li⁺, Na⁺, K⁺, Rb⁺, and Cs⁺ exhibit pronounced preferences for the formation of cryptands of certain sizes and donor numbers, and the selection is rationalized by DFT calculations. Reported is also the first self-assembly of a chiral orthoester cryptate and a preliminary study on the use of stereoisomers as subcomponents.

A lid for every pot: Cryptands based on orthoester bridgeheads offer an elegant entry to experiments in which a metal ion selects its preferred host from a dynamic mixture of competing subcomponents. In such dynamic mixtures the alkali metal ions Li⁺, Na⁺, K⁺, Rb⁺, and Cs⁺ exhibit pronounced preferences for the formation of cryptands of certain sizes and donor numbers.

Light-driven conformational changes in a macrocyclic host enable the controlled encapsulation and release of guest species. In their Communication on page 16096 ff., J. del Barrio, O. A. Scherman and co-workers describe the rational design and synthesis of a photoresponsive macrocycle that displays remarkable binding affinity towards a set of guest molecules, including N-oxides and carboxylates. The guest molecules are expelled from the macrocyclic cavity when the complex is exposed to UV light.

A photocatalytic method for the aerobic oxidative cleavage of C=C bonds has been developed. Electron-rich aromatic disulfides were employed as photocatalyst. Upon visible-light irradiation, typical mono- and multi-substituted aromatic olefins could be converted into ketones and aldehydes at ambient temperature. Experimental and computational studies suggest that a disulfide–olefin charge-transfer complex is possibly responsible for the unconventional dissociation of S−S bond under visible light.

Mild and metal-free: A photocatalytic method for the aerobic oxidative cleavage of C=C bonds has been developed with electron-rich aromatic disulfides as photocatalyst. Upon visible-light irradiation, aromatic olefins were converted into ketones and aldehydes at ambient temperature. A disulfide–olefin charge-transfer complex is possibly responsible for the S−S bond dissociation.