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To develop new hybrid micelles with alkyl/polyaromatic core–shell structures, we synthesized umbrella‐shaped amphiphiles bearing a bent anthracene dimer with a linear alkyl chain (i.e. octyl and hexadecyl groups). The amphiphiles quantitatively assemble into spherical micelles (~2–3 nm in core diameter), possessing an alkylated cavity surrounded by a polyaromatic framework, in water. The alkylation significantly enhances the stability of the micellar structures against dilution (up to 9 μM) and heat (up to >120 °C). The highly condensed hexadecyl core of the hybrid micelle, as indicated by solvatochromic guest probes, displays increased uptake ability toward large alkylated metallodyes. Interestingly, efficient uptake of aromatic macrocycles (i.e. [n]cycloparaphenylenes) by the present micelle provides pseudorotaxane‐shaped host–guest composites with high emissivity (ΦF=up to 35 %). Internal multi‐alkylation of an aromatic micelle can thus successfully enhance its assembly stability/guest uptake functions. [ABSTRACT FROM AUTHOR]

A ferrocene‐based capsule is spontaneously and quantitatively formed in water by the assembly of bent amphiphiles carrying two ferrocene units. The disassembly and assembly of the new organometallic capsule, with a well‐defined and highly condensed ferrocene core, are demonstrated by chemical redox stimuli in a fully reversible fashion under ambient conditions. In contrast to previously reported multiferrocene assemblies, only the present capsule efficiently encapsulates typical organic/inorganic dyes as well as electron‐accepting molecules in water. As a result, unusual host‐guest charge‐transfer (CT) interactions, displaying relatively wide absorption bands in the visible to near‐infrared region (λ=650–1350 nm), are observed upon the encapsulation of acceptors (i.e. chloranil and TCNQ). The resultant encapsulation‐induced CT interactions can be released by a redox stimulus through the disassembly of the capsule. [ABSTRACT FROM AUTHOR]

Host–guest assemblies of a designed 1,4-bis(diarylamino)naphthalene and V-shaped aromatic amphiphiles consisting of two pentamethylbenzene moieties bridged by an m -phenylene unit bearing two hydrophilic side chains emerged as highly reducing photoredox catalysis systems in water. An efficient demethoxylative hydrogen transfer of Weinreb amides has been developed. The present supramolecular strategy permits facile tuning of visible-light photoredox catalysis in water. [ABSTRACT FROM AUTHOR]

Catalyst‐ and reagent‐free reactions are powerful tools creating various functional molecules and materials. However, such chemical bonds are usually hydrolysable or require specific functional groups, which limits their use in aqueous media. Herein, we report the development of new amphiphiles through the Staudinger reaction. Simple mixing of chlorinated aryl azide with a hydrophilic moiety and various triarylphosphines (PAr3) gave rise to azaylide‐based amphiphiles NPAr3, rapidly and quantitatively. The obtained NPAr3 formed ca. 2 nm‐sized spherical aggregates (NPAr3)n in water. The hydrolysis of NPAr3 was significantly suppressed as compared with those of non‐chlorinated amphiphiles nNPAr3. Computational studies revealed that the stability is mainly governed by the decrease in LUMO around the phosphorus atom owing to the o‐substituted halogen groups. Furthermore, hydrophobic dyes such as Nile red and BODIPY were encapsulated by the spherical aggregates (NPAr3)n in water. [ABSTRACT FROM AUTHOR]

An aromatic oligomer micelle, featuring both high stability and high uptake ability, was quantitatively formed in water from amphiphilic oligomers, composed of three bent polyaromatic amphiphiles connected alternately by two hydrophilic chains. The well‐defined micelle, with a diameter of ca. 2 nm, remains intact even under highly diluted conditions (ca. 3 μM) and at elevated temperature (>130 °C), due to the polyaromatic chelate effect. The thermodynamic studies reveal that large enthalpic gain (ΔH=−110 kJ mol−1) is the key for the micelle formation. The oligomer micelle selectively encapsulates unsubstituted oligothiophenes (≥4‐mer) to a high degree and the resultant, aqueous host‐guest complexes display unusual emission derived from the multiply stacked oligomers. Furthermore, facile uptake and release of unsubstituted polythiophenes can be achieved using the oligomer micelle. [ABSTRACT FROM AUTHOR]

A nanocapsule composed of multiple carbazole panels (ca. 12 panels) was quantitatively generated from bent carbazole‐based amphiphiles in water. Unlike previously reported macrocycles and coordination cages bearing several carbazole panels, the resultant nanocapsule displays enhanced emissivity and improved electrochemical stability as compared with the monomeric amphiphile. The spectroscopic properties of substituted coumarin and boron‐dipyrromethene dyes can be modulated upon encapsulation by the nanocapsule in water. In the cavity, a highly blue‐shifted absorption band is observed from largely twisted coumarin dyes and two absorption bands are found from boron‐dipyrromethene dimers stacked in an unusual L‐shaped fashion. Moreover, the encapsulated dimers exhibit unique excimer‐like emission. [ABSTRACT FROM AUTHOR]

A gemini‐type amphiphilic molecule, constituted of two V‐shaped polyaromatic amphiphiles linked by a linear acetylene spacer, was synthesized. The gemini amphiphile assembles into a well‐defined aromatic micelle (ca. 2 nm in core diameter), providing higher stability in water even at low concentration (0.09 mm) and high temperature (>130 °C). Unlike common gemini amphiphiles with aliphatic chains, the present amphiphile and its micellar assembly emit green and orange fluorescence (ΦF=33 and 9 %), respectively. Despite strong and multiple π‐stacks of the polyaromatic panels of the amphiphiles, the water‐soluble gemini aromatic micelle incorporates medium‐size to large hydrophobic compounds into the frameworks. Interestingly, the guest binding capability toward large planar molecules was enhanced by more than two times through the pre‐encapsulation of spherical molecules in the cavity. [ABSTRACT FROM AUTHOR]

By the covalent linkage of two bent bisanthracene amphiphiles with a biphenyl spacer bearing hydrophilic pendants, we synthesized a new molecular clip with a C-shaped conformation. The molecular clip provides an acyclic, open cavity surrounded by four anthracene panels in water. In contrast to previous clip- and tweezers-like compounds as well as cage-shaped compounds, the C-shaped polyaromatic cavity displays unusual wide-ranging capturing abilities toward not only planar perylene-based pigments and cylindrical single-walled carbon nanotubes but also highly branched macromolecules (carbazole dendrimers). [ABSTRACT FROM AUTHOR]

A rigid tribranched scaffold with three anthracene panels was synthesized using a stereocontrolled 1,3,5-triphenylbenzene core. Grinding a mixture of the rigid scaffold and perylene leads to the quantitative formation of a spherical assembly containing stacked perylene molecules in water. The wrapped perylenes exhibit unusual Y-type excimer-like emission (λmax = ∼500 nm) at room temperature. In contrast, an analogous assembly from a flexible tribranched scaffold and perylene shows E-type emission (λmax = ∼610 nm) from the wrapped perylenes under the same conditions. [ABSTRACT FROM AUTHOR]

Metallophthalocyanines (MPcs) are very useful pigments but scarcely soluble without appropriate functional groups in common solvents. Herein, we report that bent polyaromatic amphiphiles act as excellent solubilizing reagents for nonfunctionalized MPcs and larger MPc derivatives (e.g., CuPc, perhalogenated CuPcs, Cu-naphthalocyanine, CuPc polymers, and double-decker MPcs) in neutral water upon encapsulation. The resultant MPc nanocomposites display high stability towards heat and pH change. More importantly, the encapsulated MPcs can be released by simple protocols under mild conditions both into a bulk solvent and onto glass or polymer plates. [ABSTRACT FROM AUTHOR]

Nanocarbons are synthetic carbon-rich compounds with polyaromatic frameworks that have lately attracted attention as emerging functional materials. However, their extreme hydrophobicity and aggregation peculiarity, besides their shape and size diversities, precluded their study in solution, especially in 'green' water. More convenient and general solubilizing methods of nanocarbon frameworks are required by using non-covalent supramolecular interactions. Here we report a protocol for solubilizing a wide range of nanocarbons, that is, fullerenes (C60, C70, C84, and C120), polyarenes (tetracene, pentacene, perylene, coronene, and hexabenzocoronene), and carbon nanotubes (single-walled and multi-walled CNTs), in water through manual grinding with V-shaped polyaromatic amphiphiles. The obtained aqueous nanocomposites are composed of nanocarbons encircled by the polyaromatic frameworks of the amphiphiles through multiple aromatic-aromatic interactions. Notably, the encapsulated photosensitive nanocarbons, such as tetracene, pentacene, and fullerene dimer, exhibit unusual stability toward UV/Vis light. [ABSTRACT FROM AUTHOR]

Atropselektive Bildung: Ein amphiphiles cis ‐ Atropisomer mit drei Anthracenringen und vier Sulfonatgruppen bildet über hydrophobe und Aren ‐ Aren ‐ Wechselwirkungen eine molekulare Kapsel. Die dimere Kapsel bindet kleine Gastmoleküle, und die entstehenden Wirt ‐ Gast ‐ Komplexe zeigen Charge ‐ Transfer ‐ Wechselwirkungen, die mit Änderungen der Wirt ‐ Emission einhergehen. [ABSTRACT FROM AUTHOR]

Linear alkanes are essential building blocks for natural and artificial assemblies in water. As compared with typical, linear alkane-based micelles and recent aromatic micelles, we herein develop a cycloalkane-based micelle, consisting of bent amphiphiles with two cyclohexyl frameworks. This uncommon type of micelle, with a spherical core diameter of ~ 2 nm, forms in water in a spontaneous and quantitative manner. The cycloalkane-based, hydrophobic cavity displays peculiar host abilities as follows: (i) highly efficient uptake of sterically demanding Zn(II)-tetraphenylporphyrin and rubrene dyes, (ii) selective uptake of substituted Cu(II)-phthalocyanines and spherical nanocarbons, and (iii) uptake-induced solution-state emission of [Au(I)-dimethylpyrazolate]3 in water. These host functions toward the large metal-complex and other guests studied herein remain unaccomplished by previously reported micelles and supramolecular containers. Typical micelles are molecular assemblies composed of amphiphiles bearing linear alkyl chains. Herein, the authors present an uncommon type of cycloalkane-based bent amphiphile and its micelle which encapsulates large metal- complexes with high uptake efficiency, selectivity, and emissivity in water. [ABSTRACT FROM AUTHOR]

A new protocol for solubilizing various nanocarbons such as spherical fullerenes Cn (e.g., n=60, 70, and 84), planar polyarenes (e.g., tetracene, coronene, and hexabenzocoronene), and cylindrical carbon nanotubes (e.g., SWCNTs and MWCNTs) in water through manual grinding with V ‐ shaped polyaromatic amphiphiles is described in the Full Paper by K. Kondo and M. Yoshizawa et al. on page 12741 ff. The obtained aqueous nanocomposites are composed of nanocarbons encircled by the polyaromatic panels of the amphiphiles through multiple aromatic – aromatic interactions. Notably, the encapsulated photosensitive nanocarbons, such as tetracene and fullerene dimer C120 , exhibit high stability toward light. [ABSTRACT FROM AUTHOR]