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Oligothiophene derivatives have been extensively studied as p‐type semiconducting materials in organic electronics applications. This work reports the synthesis, self‐assembly and photophysical properties of acceptor–donor–acceptor (A–D–A)‐type oligothiophene derivatives by end‐group engineering of quaterthiophene (QT) with naphthalene monoimide (NMI) chromophores that are further connected to a trialkoxy benzamide wedge. Conjugation to the NMI units reduces the HOMO–LUMO gap significantly, and consequently the absorption spectrum exhibits a bathochromic shift of about 50 nm compared with QT. Furthermore, extended H‐bonding interactions among the amido groups of the peripheral wedges produce entangled fibrillar nanostructures and gelation in hydrocarbon solvents such as methylcyclohexane, wherein the A–D–A chromophore exhibits typical H‐aggregation. On the contrary, the fact that the same chromophore, lacking only the amido units, does not produce gels or H‐aggregates indicates strong impact of H‐bonding on the self‐assembly. Computational studies revealed the electronic properties of the chromophore and predicted the geometry of a dimer in the H‐aggregate that reasonably matches with the experimental results. Bulk electrical conductivity measurements determined an excellent conductivity of 2.3×10−2 S cm−1 for the H‐aggregated system (OT‐1), which is two orders of magnitude higher than that of the same chromophore lacking the amido groups (OT‐2). [ABSTRACT FROM AUTHOR]

Herein we describe the H‐bonding‐regulated nanostructure, thermodynamics, and multivalent binding of two bolaamphiphiles NDI‐1 and NDI‐2 consisting of a hydrophobic naphthalene diimide connected to a hydrophilic wedge by a H‐bonding group and a glucose moiety on its two arms. NDI‐1 and NDI‐2 differ by the single H‐bonding group, namely, hydrazide or amide, which triggers the formation of vesicles and cylindrical micelles, respectively. Although the extended H‐bonding ensures stacking with head‐to‐head orientation and the formation of an array of the appended glucose moieties in both systems, the adaptive cylindrical structure exhibited superior multivalent binding with concanavalin A (ConA) to that of the vesicle. A control amphiphile lacking a H‐bonding group assembled with a random lateral orientation to produce spherical micelles without any notable multivalent binding. Bonded with a purpose: Two bolaamphiphiles consisting of a hydrophobic naphthalene diimide unit connected at one end to a hydrophilic wedge by a H‐bonding group (hydrazide or amide) and at the other to a glucose moiety showed distinct H‐bonding‐regulated behavior with the formation of vesicles or cylindrical micelles (see picture). The adaptive cylindrical micelles formed by amide H‐bonding exhibited superior multivalent binding with concanavalin A. [ABSTRACT FROM AUTHOR]

The stimuli‐responsive supramolecular co‐assembly of two π‐amphiphiles, NDI‐1 and Py‐1, in which an acceptor (A) (naphthalene diimide) and a donor (D) (pyrene) chromophore, respectively, serve as the hydrophobic segment, is described. In addition, both contain an amide group in a designated location so that H‐bonding and D–A charge‐transfer (CT) interactions can operate simultaneously. H‐bonding among the amide groups not only enhanced the CT interaction promoted by the alternating D–A stacking propensity, but also fixed the lateral orientation of the two chromophores and thus compelled the anionic and nonionic hydrophilic head groups, appended with the D and A amphiphiles, respectively, to remain segregated on two opposite sides of the amphiphilic alternating supramolecular copolymer. This copolymer showed spontaneous polymersome assembly with the D‐appended anionic groups displayed at the outer surface, whereas the A‐appended hydrophilic wedge converged at the inner lacuna. In contrast, spherical or cylindrical micellar structures were produced by Py‐1 and NDI‐1, respectively. Effective functional‐group display in the D–A supramolecular polymersome enabled protein‐surface recognition and inhibition of the enzymatic activity of Cht. Under a reducing environment, formation of NDI.− jeopardized the D–A interaction and thus the A chromophores were ejected out of the membrane of the polymersome causing its gradual contraction in size by >75 %. D–A supramolecular polymersomes also exhibited a lower critical solution temperature that could be tuned across a temperature window of 40 to 70 °C by varying the ratio of the A and D components in the alternating supramolecular copolymer. H‐bonding promoted directional alternating donor–acceptor stacking leads to formation of a multi‐stimuli‐responsive supramolecular polymersome with the desired functional‐group display (see scheme). In contrast, the individual components form a micelle and hydrogel, respectively. [ABSTRACT FROM AUTHOR]

Abstract: This Communication reports photo‐triggered supramolecular assembly of a naphthalene‐diimide (NDI) derivative, appended with a photo‐labile ortho‐nitrobenzyl (ONB)‐ester protected carboxylic acid. Photo‐irradiation produces the free COOH group which facilitates H‐bonding‐driven face‐to‐face stacking of the NDI chromophores producing an ultra‐thin (height <2.0 nm) two‐dimensional (2D) nanosheet. In contrast, spontaneous supramolecular assembly of the same active monomer exhibits entirely different features such as uncontrolled growth, J‐aggregation and fibrillar morphology. A completely different pathway for photo‐triggered assembly is attributed to the dual function of the photo‐caged pro‐monomer in i) producing the carboxylic acid in controlled manner and ii) simultaneously inhibiting the spontaneous J‐aggregation of the photo‐generated monomers by ester‐carboxylic acid H‐bonding and in turn directing a distinct growth mechanism. [ABSTRACT FROM AUTHOR]

A naphthalene-diimide appended carboxylic acid either spontaneously self-assembles (P) by an open-chain H-bonding or can be arrested in an intra-molecularly H-bonded monomeric state (M) depending on the sample preparation method. Sonication of P produces a seed (S) that triggers controllable supramolecular polymerization (SP) of M via a chain growth route with first order kinetics, a tunable mesoscopic structure and a living nature as demonstrated by the chain-extension up to three cycles. SP of an achiral M, initiated by a chiral S, illustrates chiral amplification by the “sergeant and soldiers” effect. [ABSTRACT FROM AUTHOR]

This article discloses hydrogen-bonding driven supramolecular polymerization of a core-substituted naphthalene-diimide derivative NDI-1, which exhibits J-aggregation in all tested hydrocarbon solvents; however, spontaneous gelation was noticed only in linear alkanes in contrast to free flowing solution in their cyclic analogs. Mechanistic investigation by variable-temperature UV/Vis studies and analyzing the data by using an appropriate model(s) elucidates a highly cooperative self-assembly pathway in linear hydrocarbons (heptane, octane, nonane, or decane) in sharp contrast to cyclohexane or methylcyclohexane in which an ill-defined polymerization was noticed. This is attributed to the direct participation of linear alkanes in the nucleation process by favorable mixing with the peripheral alkyl chains of the NDI monomer, which appears not to be the case for cyclic alkanes owing to geometry mismatch. Although all tested linear hydrocarbons induced nucleation-elongation growth, the thermodynamic parameters were found to depend on the chain length of the alkane. The morphology of the self-assembled polymer was strongly dependent on the growth mechanism as we noticed fibrillar networks and short-length rods, respectively, in decane and methylcyclohexane (MCH). However, in the presence of a small amount of additive (preformed fiber in decane; added in situ or post self-assembly) a fibrillar structure was noticed also in MCH, corroborating the self-assembly in solution, which adopted a cooperative mechanism similar to linear alkanes. [ABSTRACT FROM AUTHOR]

We report molecular interaction-driven self-assembly of supramolecularly engineered amphiphilic macromolecules (SEAM) containing a single supramolecular structure-directing unit (SSDU) consisting of an H-bonding group connected to a naphthalene diimide chromophore. Two such SEAMs, P1-50 and P2-50, having the identical chemical structure and hydrophobic/hydrophilic balance, exhibit distinct self-assembled structures (polymersome and cylindrical micelle, respectively) due to a difference in the H-bonding group (hydrazide or amide, respectively) of the single SSDU. When mixed together, P1-50 and P2-50 adopted self-sorted assembly. For either series of polymers, variation in the hydrophobic/hydrophilic balance does not alter the morphology reconfirming that self-assembly is primarily driven by directional molecular interaction which is capable of overruling the existing norms in packing parameter-dependent morphology control in an immiscibility-driven block copolymer assembly. [ABSTRACT FROM AUTHOR]

Photo-initiated supramolecular polymerization of a naphthalenediimide (NDI-1) derivative containing an ortho-nitrobenzyl (ONB)-protected amide group is demonstrated. In a hydrocarbon solvent (methylcyclohexane), it remains as monomer. Upon photo-irradiation, deprotection of the ONB group produces NDI-2 with a free amide group, which drives supramolecular polymerization by self-complementary H-bonding between the amide groups, leading to gelation. The polymerization rate can be controlled by tuning the energy of the light source. During photopolymerization, a gradual increase in hydrodynamic radius and viscosity is noticed. More interestingly, the morphology of the supramolecular polymer of NDI-2, produced by photo-irradiation, was a spherulite, which is in sharp contrast with the fibrillar morphology of NDI-2 polymer, when assembled spontaneously without a phototrigger. This is ascribed to the ability of the ONB-caged pro-monomer (NDI-1) to act as a chain-stopper by forming a H-bonded complex with the active monomer during the growth of the supramolecular polymer under photo-irradiation. [ABSTRACT FROM AUTHOR]

This communication reveals the H-bonding driven supramolecular assembly of a sulfur-substituted naphthalenediimide leading to the formation of very strong (Tg ＞ 90 °C) organogel in aliphatic hydrocarbons. Mechanistic investigation reveals nucleation–elongation pathway for self-assembly. Photophysical studies show explicit features of classical J-aggregation which reduces the non-radiative fluorescence rate constant considerably and thus results in a remarkable fluorescence enhancement (ΦPL increases from 1% to 30%) which is unprecedented in the entire NDI literature. [ABSTRACT FROM AUTHOR]

In this review we have collated various supramolecular designs, all surrounding H-bonding among well-known functional groups (peptides, nucleic acids, amides, ureas, carboxylic acids, pyridine-hydroxyls, urethanes, imides and others), to dictate self-assembly of naphthalenediimide (NDI) π-systems (both small molecules and polymeric building blocks) that exhibit several exciting features including strong propensity for π–π interactions, π-acidity, excellent n-type semiconductivity, CT-complexation, ion–π interactions, ring-substitution dependent redox properties and photophysical properties. This article reveals that H-bonding can indeed serve as a very powerful and versatile tool to programmed self-assembly of a single or multiple dye system producing a wide range of tailored soft materials, including fibrillar gels, chromonic mesophases, foldamers, nanotubes, vesicles, reverse micelles and polymersomes, both in water and organic medium with distinct photophysical properties, charge transport properties, conductivity properties and functional group displays that are highly relevant in the fields of biology and organic electronics. [ABSTRACT FROM AUTHOR]

A unique supramolecular strategy enables the unidirectional assembly of two bola-shaped unsymmetric π-amphiphiles, NDI-1 and NDI-2, which feature a naphthalene-diimide chromophore connected to nonionic and anionic head groups on opposite arms. The amphiphiles differ only in the location of a hydrazide group, which is placed either on the nonionic or on the anionic arm of NDI-1 and NDI-2, respectively. The formation of hydrogen bonds between the hydrazides, which compensates for electrostatic and steric factors, promotes unidirectional alignment and the formation of monolayer vesicles. The zeta potentials and cation-assisted quantitative precipitation reveal negatively charged and nonionic outer surfaces for NDI-1 and NDI-2, respectively, indicating that hydrogen bonding also dictates the directionality of the monolayer curvature, ensuring that in both cases, the hydrazides remain at the inner wall to benefit from stronger hydrogen bonding where they are in closer proximity. This is reflected in their different abilities to inhibit α-chymotrypsin, which possesses a positively charged surface: NDI-1 induced an inhibition of 80 % whereas hardly any inhibition was observed with NDI-2. [ABSTRACT FROM AUTHOR]

Unique H-bonding motifs of 1,3-dihydroxyl derivatives involving simultaneous intra- and inter-molecular H-bonding results in extended organization of pendant chromophores with a spatial distance suitable for π–π interaction. A preformed assembly with appended acceptor units exhibits host–guest interaction with specific donors by charge-transfer complex formation. [ABSTRACT FROM AUTHOR]

In diesem Kurzaufsatz werden supramolekulare Anordnungen diskutiert, bei denen eine (nichtkovalente) Charge ‐ Transfer(CT) ‐ Wechselwirkung zwischen einem organischen Donor und Akzeptor genutzt wird, um Strukturen wie fibrilläre Gele, Micellen, Vesikel, Nanoröhren, Foldamere, konformativ eingeschränkte Makromoleküle und flüssigkristalline Phasen zu erzeugen. Nicht zuletzt auch nach dem Vorbild der Natur haben Chemiker die Wasserstoffbrücke als ein Hilfsmittel für die Herstellung von supramolekularen Anordnungen aus einer vielfältigen Auswahl an abiotischen Bausteinen umfassend genutzt. Als Strukturmotiv können CT ‐ Komplexe hinsichtlich ihrem gerichteten Charakter und ihrer Komplementarität mit Wasserstoffbrücken ‐ gebundenen Komplexen verglichen werden. Vorteile von CT ‐ Wechselwirkungen sind eine breite Lösungsmitteltoleranz und ihre einfache spektroskopische Messung. Ein potentieller Nachteil ist jedoch ihre geringe Assoziationskonstante. Um dieses Hindernis zu überwinden, wurden verschiedene Strategien entwickelt, z. B. die Verstärkung von CT ‐ Wechselwirkungen mit zusätzlichen nichtkovalenten Kräften, ohne dass die Art der Donor ‐ Akzeptor ‐ Stapelung beeinträchtigt wird. Ein besonders vielversprechendes Anwendungsfeld von Donor ‐ Akzeptor ‐ CT ‐ Komplexen ist die organische Elektronik. Farbenspiel: Durch die alternierende Stapelung aromatischer Donor ‐ und Akzeptor ‐ Bausteine über komplementäre und gerichtete Charge ‐ Transfer ‐ Wechselwirkungen sind vielfältige Arten supramolekular aufgebauter Materialien zugänglich, z. B. Micellen, Vesikel, Nanoröhren, fibrilläre Gele, gefaltete Polymere, Netzwerke und flüssigkristalline Phasen. [ABSTRACT FROM AUTHOR]

We have collated various supramolecular designs that utilize organic donor-acceptor CT complexation to generate noncovalently co-assembled structures including fibrillar gels, micelles, vesicles, nanotubes, foldamers, conformationally restricted macromolecules, and liquid crystalline phases. Possibly inspired by nature, chemists have extensively used hydrogen bonding as a tool for supramolecular assemblies of a diverse range of abiotic building blocks. As a structural motif, CT complexes can be compared to hydrogen-bonded complexes in its directional nature and complementarities. Additional advantages of CT interactions include wider solvent tolerance and easy spectroscopic probing. Nevertheless the major limitation is their low association constant. This article shows different strategies have evolved over the years to overcome this drawback by reinforcing the CT interactions with auxiliary noncovalent forces without hampering the alternate stacking mode. Emerging reports on promising CT complexes in organic electronics are intimately related to various supramolecular designs that one can postulate based on donor-acceptor CT interactions. [ABSTRACT FROM AUTHOR]

Self-assembly and photophysical propertiesof a trialkoxybenzhydrazide-functionalizednaphthalene diimide (NDI)-appended amphiphilic polymer are reported.Hydrophobically assisted H-bonding among hydrazides in conjunctionwith π-stacking among NDI produced vesicles in aqueous mediumwith astonishingly high kinetic as well as thermodynamic stabilitywhich showed enhanced emission in the aggregated state. In benzene,rarely reported reverse vesicular assembly was formed with dual containerproperty with almost identical photophysical properties and stabilityas observed in water. Both vesicular and reverse-vesicular assemblieswere found to remain stable at the benzene–water interface. [ABSTRACT FROM AUTHOR]

Formation of micelle‐type assembly from supramolecular complexation of a surfactant and an oppositely charged homopolymer is demonstrated. The lower CAC observed for these assemblies suggest that the electrostatic interaction provides an amphiphilic homopolymer‐like structure. The stimulus‐induced disassembly of these supramolecular structures has been accomplished with variations in redox characteristics, ionic strength, and pH of the medium. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1052–1060, 2009 [ABSTRACT FROM AUTHOR]

Three component supramolecular assemblies from a mixture of an aromatic donor (D), acceptor (A) and external structure directing agent (ESDA) are achieved by orthogonal noncovalent interactions involving two different types of H-bonding and alternate D–A stacking. An ESDA containing amide or urea produces a charge–transfer gel and sol, respectively, owing to their contrasting morphology. [ABSTRACT FROM AUTHOR]

An effective supramolecular strategy for self-sorting between naphthalene-diimide (NDI) acceptor and dialkoxy-naphthalene (DAN) donor organogelators is reported. The concept is based on mismatch in the placement of the two amide functionalities in the donor and acceptor chromophores so that self-sorting ensured maximum effect of H-bonding. [ABSTRACT FROM AUTHOR]

Supramolecular induction of chirality to a π-stacked dialkoxynaphthalene (DAN)-fiber (made of achiral building blocks) from a neighbouring helical naphthalenediimide (NDI)-fiber is reported. CD-studies helped in understanding the nature of co-assembly in the donor–acceptor chromophore mixture from molecular to macroscopic scale. [ABSTRACT FROM AUTHOR]

Supramolecular Assembly In their Communication on page 1606 ff., S. Ghosh et al. describe the generation of two bolaamphiphiles with different H‐bonding motifs (hydrazide or amide) and their distinct behavior in the multivalent binding of concanavalin A. [ABSTRACT FROM AUTHOR]

In the present examples of self ‐ assembly of a naphthalene – diimide building block, linear hydrocarbon solvents directly participate in the nucleation step owing to a geometry allowed, favorable mixing with peripheral alkyl chains of the monomer, which leads to a cooperative supramolecular polymerization pathway. In sharp contrast, lack of such efficient nucleation leads to ill ‐ defined polymerization pathway in cyclic hydrocarbons. However, in the presence of a small amount of additive (preformed fiber in linear alkanes), cooperative polymerization pathway could be retrieved even in cyclic alkanes. For more information, see the Full Paper by S. Ghosh et al. on page 10536 ff. [ABSTRACT FROM AUTHOR]

Review: 113 refs. [ABSTRACT FROM AUTHOR]

Supramolecular Chemistry Complementary donor (D)–acceptor (A) chromophores assemble with long‐range order by hydrogen bonding and produce charge‐transfer organogels. In the presence of excess donor, extended fibrils get truncated and the gel is destroyed. For more details see the Communication by S. Ghosh, A. Paul et al. on page 1908 ff. The authors thank Mr. Gopal Krishna Manna for his help in the preparation of the frontispiece. [ABSTRACT FROM AUTHOR]

Review: 159 refs. [ABSTRACT FROM AUTHOR]