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The amplification of asymmetry in supramolecular polymers has recently garnered significant attention. While asymmetry amplification has predominantly been explored under thermodynamic conditions, the kinetic aspect of this process unveils intriguing observations, yet is scarcely reported in the literature. Herein, drawing inspiration from macromolecular systems, we propose a novel strategy for enhancing asymmetry in supramolecular polymers through a seed-induced supramolecular polymerization approach under kinetic conditions, employing a naphthalene diimide-derived monomer (ANSG) for template-induced supramolecular polymerization, utilizing adenosine triphosphate (ATP) and pyrophosphate (PPi) as templates. A chiral seed comprising [ANSG-ATP]S effectively amplifies the overall supramolecular asymmetry when exposed to a mixture of achiral templates (PPi) and monomers (ANSG), owing to its efficient seeding characteristics under kinetic conditions. As a result of efficient co-operativity, conversely, employing an achiral seed [ANSG-PPi]S in a mixture of chiral templates (ATP) and monomers (ANSG) results in the attenuation of asymmetry, highlighting the effective modulation achievable through the seeding approach, -an unprecedented observation in the field. Exploiting the efficient aggregation-induced emission enhancement (AIEE) of the resultant supramolecular polymers further extends the amplification and attenuation of circularly polarized luminescence (CPL) as a potential function., (© 2024 Wiley‐VCH GmbH.)

Efficient circularly polarized luminescence (CPL) from purely organic molecules holds great promise for applications in displays, sensing, and bioimaging. However, achieving high dissymmetry values (g lum ) from organic chromophores remains a significant challenge. Herein, we present a bioinspired approach using adenosine triphosphate (ATP)-triggered supramolecular polymerization of a naphthalene diimide-derived monomer (ANSG) to induce CPL with a remarkable g lum value of 1.1×10 -2 . The ANSG molecules undergo a templated, chiral self-assembly through a cooperative growth mechanism in the presence of ATP, resulting in scrolled nanotubes with aggregation-induced enhanced emission (AIEE) and induced CPL. Furthermore, we demonstrate the concept of chiroptical amplification of induced CPL by efficiently amplifying asymmetry using a mixture of chiral ATP and achiral pyrophosphate. This innovative approach opens numerous opportunities in the emerging field of circularly polarized luminescence., (© 2023 Wiley-VCH GmbH.)

Chiral organic phosphors with circularly polarized room-temperature phosphorescence (CPP) provide new prospects to the realm of circularly polarized luminescence (CPL) materials, owing to the long-lived triplet states and persistent emission. Although several molecular designs show efficient room-temperature phosphorescence (RTP), realization of ambient organic CPP remains a formidable challenge. Herein, we introduce a chiral bischromophoric phosphor design to realize ambient CPP emission by appending molecular phosphors to a chiral diaminocyclohexane core. Thus, solution-processable polymer films of the trans-1,2-diaminocyclohexane (DAC) chiral cores with heavy-atom substituted pyromellitic diimide phosphors, exhibits one of the most efficient exclusive CPP emissions with high phosphorescence quantum yield (≈18 % in air and ≈46 % under vacuum) and significant luminescence dissymmetry factor (|g lum |≈4.0×10 -3 )., (© 2022 Wiley-VCH GmbH.)

Solution phase room-temperature phosphorescence (RTP) from organic phosphors is seldom realized. Herein we report one of the highest quantum yield solution state RTP (ca. 41.8 %) in water, from a structurally simple phthalimide phosphor, by employing an organic-inorganic supramolecular scaffolding strategy. We further use these supramolecular hybrid phosphors as a light-harvesting scaffold to achieve delayed fluorescence from orthogonally anchored Sulforhodamine acceptor dyes via an efficient triplet to singlet Förster resonance energy transfer (TS-FRET), which is rarely achieved in solution. Electrostatic cross-linking of the inorganic scaffold at higher concentrations further facilitates the formation of self-standing hydrogels with efficient RTP and energy-transfer mediated long-lived fluorescence., (© 2021 Wiley-VCH GmbH.)

Synthesis of supramolecular block co-polymers (BCP) with small monomers and predictive sequence requires elegant molecular design and synthetic strategies. Herein we report the unparalleled synthesis of tri-component supramolecular BCPs with tunable microstructure by a kinetically controlled sequential seeded supramolecular polymerization of fluorescent π-conjugated monomers. Core-substituted naphthalene diimide (cNDI) derivatives with different core substitutions and appended with β-sheet forming peptide side chains provide perfect monomer design with spectral complementarity, pathway complexity and minimal structural mismatch to synthesize and characterize the multi-component BCPs. The distinct fluorescent nature of various cNDI monomers aids the spectroscopic probing of the seeded growth process and the microscopic visualization of resultant supramolecular BCPs using Structured Illumination Microscopy (SIM). Kinetically controlled sequential seeded supramolecular polymerization presented here is reminiscent of the multi-step synthesis of covalent BCPs via living chain polymerization. These findings provide a promising platform for constructing unique functional organic heterostructures for various optoelectronic and catalytic applications., (© 2021 Wiley-VCH GmbH.)

Arylene diimide derived ambient organic phosphors are seldom reported despite their potential structural characteristics to facilitate the triplet harvesting. In this context, highly efficient room temperature phosphorescence (RTP) from simple, heavy-atom substituted pyromellitic diimide derivatives in amorphous matrix and crystalline state is reported here. Multiple intermolecular halogen bonding interactions among these phosphors, such as halogen-carbonyl and halogen-π resulted in the modulation of phosphorescence, cyan emission from monomeric state and orange-red emission from its aggregated state, to yield twin RTP emission. Remarkably, the air-stable phosphorescence presented here own one of the highest quantum yield (≈48 %) among various organics in orange-red emissive region., (© 2021 Wiley-VCH GmbH.)

Adenosine triphosphate (ATP) is a molecular unit of energy that drives various processes in the cellular environment. In this Minireview, we discuss the potential of physical and chemical properties of ATP for the development of bio-inspired, synthetic ATP-induced supramolecular systems with dynamic, stimuli-responsive and active assembly characteristics. Molecular design rules for ATP-induced assemblies with various architectures and their stimuli-responsive structural and functional response are categorized. Special attention is given to the immense potential of ATP-fuelled designs in the nascent field of transient/non-equilibrium supramolecular polymerization for the synthesis of lifelike temporally programmable soft materials. Finally, the existing dearth and fate of ATP-driven systems for future challenges are discussed., (© 2020 Wiley-VCH GmbH.)

Stereoselective and temporally controlled supramolecular polymerizations are ubiquitous in nature and are desirable attributes for the design of chiral, well-defined functional materials. Kinetically controlled, living supramolecular polymerization (LSP) has emerged recently for the synthesis of supramolecular polymers with controlled length and narrow dispersity. On the other hand, stringent design requirements for chiral-discriminating monomers precludes the stereoselective control of the supramolecular polymer structure. Herein, a synergetic stereo- and structural control of supramolecular polymerization by the realization of an unprecedented stereoselective seed-induced LSP is reported. Homochiral and seeded growth is demonstrated with bischromophoric naphthalene diimide (NDI) enantiomers with a chiral binaphthyl amine core, exhibiting strong self-recognition abilities and pathway complexity., (© 2020 Wiley-VCH GmbH.)

Ambient afterglow luminescence from metal-free organic chromophores would provide a promising alternative to the well-explored inorganic phosphors. However, the realization of air-stable and solution-processable organic afterglow systems with long-lived triplet or singlet states remains a formidable challenge. In the present study, a delayed sensitization of the singlet state of organic dyes via phosphorescence energy transfer from organic phosphors is proposed as an alternative strategy to realize "afterglow fluorescence". This concept is demonstrated with a long-lived phosphor as the energy donor and commercially available fluorescent dyes as the energy acceptor. Triplet-to-singlet Förster-resonance energy-transfer (TS-FRET) between donor and acceptor chromophores, which are co-organized in an amorphous polymer matrix, results in tuneable yellow and red afterglow from the fluorescent acceptors. Moreover, these afterglow fluorescent hybrids are highly solution-processable and show excellent air-stability with good quantum yields., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ambient solution and amorphous state room temperature phosphorescence (RTP) from purely organic chromophores is rarely achieved. Remarkable stabilization of triplet excitons is realized to obtain deep red phosphorescence in water and in amorphous film state under ambient conditions by a unique supramolecular hybrid assembly between inorganic laponite clay and heavy atom core substituted naphthalene diimide (NDI) phosphor. Structural rigidity and oxygen tolerance of the inorganic template along with controlled molecular organization via supramolecular scaffolding are envisaged to alleviate the unprecedented aqueous phase phosphorescence., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chirality-driven self-sorting is envisaged to efficiently control functional properties in supramolecular materials. However, the challenge arises because of a lack of analytical methods to directly monitor the enantioselectivity of the resulting supramolecular assemblies. Presented herein are two fluorescent core-substituted naphthalene-diimide-based donor and acceptor molecules with minimal structural mismatch and they comprise strong self-recognizing chiral motifs to determine the self-sorting process. As a consequence, stereoselective supramolecular polymerization with an unprecedented chirality control over energy transfer has been achieved. This chirality-controlled energy transfer has been further exploited as an efficient probe to visualize microscopically the chirality driven self-sorting., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Synthetic manifestations of supramolecular chirality have extensively drawn inspiration from naturally occurring systems. Even though in biological systems conformational changes are dissipative, synthetic systems that change conformation under non-equilibrium conditions have still not been established. Herein, we attempt to alleviate this scenario by reporting a synthetic supramolecular system that undergoes temporal changes in its helical conformation as an active system at the expense of a biologically relevant chemical fuel, ATP. Use of enzymes working in tandem provides transient and switchable helices with modular lifetime and stereomutation rates., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A "chirality driven self-sorting" strategy is introduced for the controlled supramolecular organization of donor (D) and acceptor (A) molecules in multicomponent assemblies. The trans-1,2-bis(amido)cyclohexane (trans-BAC) has been identified as a supramolecular motif with strong homochiral recognition to direct this chirality controlled assembly process of enantiomers in solution. Stereoselective supramolecular polymerization of trans-BAC appended naphthalene diimide monomers (NDIs) has been probed in detail by spectroscopic and mechanistic investigations. This chirality-driven self-sorting design of enantiomeric components also offers to realize mixed and segregated D-A stacks by supramolecular co-assembly of the NDI acceptors with trans-BAC appended dialkoxynaphthalene (DAN) donor monomers. Such an unprecedented chirality control on D-A organization paves the way for the creation of supramolecular p-n nanostructures with controlled molecular-level organization., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Several covalent strategies towards surface charge-reversal in nanochannels have been reported with the purpose of manipulating ion transport. However, covalent routes lack dynamism, modularity and post-synthetic flexibility, and hence restrict their applicability in different environments. Here, we introduce a facile non-covalent approach towards charge-reversal in nanochannels (<10 nm) using strong charge-transfer interactions between dicationic viologen (acceptor) and trianionic pyranine (donor). The polarity of ion transport was switched from anion selective to ambipolar to cation selective by controlling the extent of viologen bound to the pyranine. We could also regulate the ion transport with respect to pH by selecting a donor with pH-responsive functional groups. The modularity of this approach further allows facile integration of various functional groups capable of responding to stimuli such as light and temperature to modulate the transport of ions as well as molecules., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Flexible and dynamic porous coordination polymers (PCPs) with well-defined nanospaces composed of chromophoric organic linkers provide a scaffold for encapsulation of versatile guest molecules through noncovalent interactions. PCPs thus provide a potential platform for molecular recognition. Herein, we report a flexible 3D supramolecular framework {[Zn(ndc)(o-phen)]⋅DMF}n (o-phen = 1,10-phenanthroline, ndc = 2,6-napthalenedicarboxylate) with confined nanospaces that can accommodate different electron-donating aromatic amine guests with selective turn-on emission signaling. This system serves as a molecular recognition platform through an emission-readout process. Such unprecedented tunable emission with different amines is attributed to its emissive charge-transfer (CT) complexation with o-phen linkers. In certain cases this CT emission is further amplified by energy transfer from the chromophoric linker unit ndc, as evidenced by single-crystal X-ray structural characterization., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)