Core-substituted Naphthalene Diimide Research Articles

Retraction of "A Core-Substituted Naphthalene Diimide Fluoride Sensor".

Retraction of "A Core-Substituted Naphthalene Diimide Fluoride Sensor".

Donor-Acceptor Dyads and Triads Employing Core-Substituted Naphthalene Diimides: A Synthetic and Spectro (Electrochemical) Study.

Donor-acceptor dyads and triads comprising core-substituted naphthalene diimide (NDI) chromophores and either phenothiazine or phenoxazine donors are described. Synthesis combined with electrochemical and spectroelectrochemical investigations facilitates characterisation of the various redox states of these molecules, confirming the ability to combine arrays of electron donating and accepting moieties into single species that retain the redox properties of these individual moieties.

Furan functionalized naphthalenediimide semiconductors with different N-alkyl chains for n-type organic thin-film transistor applications

Development of n-type organic semiconductors (OSCs) is necessary in order to develop complementary electronics based on organic thin-film transistors (OTFTs). In this investigation, we designed and synthesized a series of four novel imide- and core-substituted naphthalene diimide (NDI) molecules. The molecular architecture was altered via introduction of different alkyl side chains (octyl and 2-ethylhexyl) to the imide-N positions and 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) to the NDI core. The NDI-TCF derivatives are abbreviated as NDI-TCF1A, NDI-TCF1B, NDI-TCF2A, and NDI-TCF2B, using a “1” or “2” to indicate the number of TCF subunits at the NDI core, and an “A” or a “B” to indicate an octyl or a 2-ethylhexyl alkyl chain at the imide-N position, respectively. All four compounds displayed similar photophysical properties but exhibited different electrochemical properties with lower LUMO levels of −4.25 eV, −4.33 eV, −4.27 eV and −4.35 eV for NDI-TCF1A, NDI-TCF1B, NDI-TCF2A, and NDI-TCF2B, respectively. These LUMO levels suggest a capacity for electron transport. Furthermore, the NDI-TCF chromophores were incorporated into OTFTs and systematically studied on the relationship between the NDI-TCF molecular architecture and electron transport properties. NDI-TCF1A and NDI-TCF1B displayed more consistent OTFT performance than NDI-TCF2A and NDI-TCF2B. NDI-TCF1A and NDI-TCF1B exhibited low threshold voltages (VT) of −0.43 V ± 4.78 V and 6.12 V ± 6.63 V, respectively, electron mobilities (μe) of ca. 3 × 10−5 cm2V−1s−1, and on/off (ION/OFF) ratios of ca. 103. Insofar that TCF facilitates electron transport, the OTFT data suggest that the number of TCF subunits affect OTFT performance via thin-film morphology. The thin-film morphology of NDI-TCF1A, NDI-TCF1B, NDI-TCF2A, and NDI-TCF2B was studied using atomic force microscopy (AFM) technique and supported by X-ray diffraction measurements.

Front Cover: (ChemistryOpen 7/2022)

The Front Cover shows a core-substituted naphthalene diimide with dimethylamine (DDPT) groups which has been used as a reversible acid-base sensor. The color-changing tides of the sea represent the acid-base-mediated colorimetric changes the DDPT probe exhibits, switching from blue to violet. DDPT could be an efficient alternative to overcome the irreversibility of commonly used pH paper, as it also works when immobilized on paper. More information can be found in the Research Article Vishal G. More et al.

Naphthalenediimide‐Benzothiazole‐Based Chemodosimeter for Selective and Sensitive Chromogenic for Cyanide Ion

Core-substituted naphthalene diimide (NDI) with benzothiazole acts as a colorimeteric chemosensor for cyanide ion ions in presence of the interfering anions such as F−, Cl−, I−, B−, HSO4−, H2PO4−, OAc−, ClO4− and HCO3−. The NDI-1 showed high selectivity and sensitivity towards cyanide ions. The LOD of detection was found to be 85 nM. Thus, this types of derivatives may have real practical applications in the future for sensing toxic ions.

A New 'Off-On' System Based on Core-Substituted Naphthalene Diimide with Dimethylamine for Reversible Acid-Base Sensing.

A new ‘Off–On’ system designed and synthesised by functionalisation of a naphthalene diimide (NDI) core with dimethylamine produces 4,9‐bis(dimethylamino)‐2,7‐dioctylbenzo[lmn][3,8]‐phenanthroline‐1,3,6,8‐(2H,7H)‐tetraone, abbreviated as DDPT (1). DDPT 1 was synthesised using a simple strategy, namely aromatic nucleophilic substitution using Br2‐NDI with dimethylamine at 110 °C. DDPT was characterized by 1H and 13C NMR spectroscopy, ESI mass spectrometry and elemental analysis. DDPT 1 was then used for optical studies through protonation of its dimethylamine core with trifluoroacetic acid (TFA), blue‐shifting the absorption band from 600 nm to 545 nm in solution. Interestingly, the fluorescence of DDPT 1 is weak in solution with a quantum yield Φ=0.09, which is significantly enhanced to Φ=0.78 upon addition of TFA. The limit of detection (LOD) was determined to 2.77 nm. Furthermore, DDPT 1 can be used for naked eyed detection not only under UV light (365 nm) but also using visible light, as clear changes can be clearly seen upon addition of TFA. The binding constant of DDPT was calculated to 2.1×10−3 m −1. Importantly, DDPT 1 showed reversible switching by alternative addition of acid (TFA) and base (triethylamine) without loss of activity. Immobilised on paper, DDPT 1 can be used for strip‐test sensing in which the colour changes from blue to reddish when expose to TFA vapours and reverse in the presence of triethylamine vapours.

Spatiotemporal dynamics of supramolecular polymers by in situ quantitative catalyst-free hydroamination.

Implementing chemical reactivity into synthetic supramolecular polymers based on π-conjugated molecules has been of great interest to create functional materials with spatiotemporal dynamic properties. However, the development of an in situ chemical reaction within supramolecular polymers is still in its infancy, because one needs to design optimal π-conjugated monomers having excellent reactivity under mild conditions possibly without byproducts or a catalyst. Herein we report the synthesis of a supramolecular polymer based on ethynyl core-substituted naphthalenediimide (S-NDI2) molecules that react with various amines quantitatively in a nonpolar solvent, without a catalyst, at 298 K. Most interestingly, the in situ reaction of the S-NDI2 supramolecular polymer with a linear aliphatic diamine proceeded much faster than the homogeneous reaction of a monomeric naphthalenediimide with the same diamine, affording diamine-linked S-NDI2 oligomers and polymers. The acceleration of in situ hydroamination was presumably due to rapid intra-supramolecular cross-linking between ethynyl and amino groups fixed in close proximity within the supramolecular polymer. Such intra-supramolecular cross-linking did not occur efficiently with an incompatible diamine. The systematic kinetic studies of in situ catalyst-free hydroamination within supramolecular polymers provide us with a useful, facile and versatile tool kit for designing dynamic supramolecular polymeric materials based on electron-deficient π-conjugated monomers.

Cooperative self-assembling process of core-substituted naphthalenediimide induced by amino-yne click reaction.

We report a cooperative (i.e., nucleation-elongation) self-assembling process of a core-substituted naphthalenediimide induced by a catalyst-free amino-yne click reaction at 298 K. The self-assembling process was initiated immediately in the presence of nuclei (seeds). The combination of the click reaction and the seeded self-assembling process paves the way for precise control over supramolecular assemblies of electron-deficient π-systems.

Photochromic and Room Temperature Phosphorescent Donor-Acceptor Hybrid Crystals Regulated by Core-Substituted Naphthalenediimides.

Donor-acceptor (D-A) hybrid crystals are an emerging kind of crystalline hybrid material composed of semiconductive inorganic donors and organic acceptors. Except for the intrinsic photochromism, recently we have reported that the anion-π polyoxometalate (POM)/naphthalenediimide (NDI) hybrid crystals could produce an interesting room temperature phosphorescence (RTP) quantum yield up to 7.2%. Herein, we extended into core-substituted NDIs and anticipated the regulation of their photochromic and RTP properties. Thus, two hybrid crystals, namely (H4BDMPy-Br2NDI)·(NMP)4·(HPW12O40) (1) and (H4BDMPy-I2NDI)·(HPW12O40) (2) (H2BDMPy-Br2NDI: N,N'-bis(3,5-dimethylpyrazolyl)-2,6-dibromo-1,4,5,8-naphthalenediimide and H2BDMPy-I2NDI: N,N'-bis(3,5-dimethylpyrazolyl)-2,6-diiodide-1,4,5,8-naphthalenediimide), have been synthesized from phosphotungstic anions (PW12O403-) and Br or I core-substituted NDIs. Compared to the core-unsubstituted analogues (H4BDMPy-NDI)·(NMP)4·(HPW12O40) (3), 2 with photosensitive iodine substituents is more sensitive to light, which can become discolored under natural light. As a result of the heavy-atom effect, hybrid 1 exhibits remarkable RTP with the quantum yield up to 10.2% and a lifetime of 1.14 ms.

Solvent-Directed Transformation of the Self-assembly and Optical Property of a Peptide-Appended Core-Substituted Naphthelenediimide and Selective Detection of Nitrite Ions in an Aqueous Medium.

This study vividly displays the different self-assembling behavior and consequent tuning of the fluorescence property of a peptide-appended core-substituted naphthalenediimide (N1) in the aliphatic hydrocarbon solvents (n-hexane/n-decane/methyl cyclohexane) and in an aqueous medium within micelles. The N1 is highly fluorescent in the monomeric state and self-aggregates in a hydrocarbon solvent, exhibiting "H-type" or "face-to-face" stacking as indicated by a blue shift of absorption maxima in the UV-vis spectrum. In the H-aggregated state, the fluorescence emission of N1 changes to green from the yellow emission obtained in the monomeric state. In the presence of a micelle-forming surfactant, cetyl trimethylammonium bromide (CTAB), the N1 is found to be dispersed in a water medium. Interestingly, upon encapsulation of N1 into the micelle, the molecule alters its self-assembling pattern and optical property compared to its behavior in the hydrocarbon solvent. The N1 exhibits "edge-to-edge" stacking or J aggregates inside the micelle as indicated by the UV-vis spectroscopic study, which shows a red shift of the absorption maxima compared to that in the monomeric state. The fluorescence emission also differs in the water medium with the NDI derivative exhibiting red emission. FT-IR studies reveal that all amide NHs of N1 are hydrogen-bonded within the micelle (in the J-aggregated state), whereas both non-bonding and hydrogen-bonding amide NHs are present in the H-aggregated state. This is a wonderful example of solvent-mediated transformation of the aggregation pattern (from H to J) and solvatochromism of emission over a wide range from green in the H-aggregated state to yellow in the monomeric state and orangish-red in the J-aggregated state. Moreover, the J aggregate has been successfully utilized for selective and sensitive detection of nitrite ions in water even in the presence of other common anions (NO3-, SO42-, HSO4-, CO32-, and Cl-).

Tricomponent Supramolecular Multiblock Copolymers with Tunable Composition via Sequential Seeded Growth.

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.

Novel core-substituted naphthalene diimide-based conjugated polymers for electrochromic applications

The strategic implementation of using a core-substituted naphthalene diimide derivative to electropolymerize an ionized polymer for a better electrochromic performance is proposed.

Influences of the number of 2-ethylhexylamine chain substituents on electron transport characteristics of core-substituted naphthalene diimide analogues

We designed and synthesized a series of naphthalenediimide (NDI) derivatives through core-substitution (coded as cNDI) with various number of 2-ethyl-hexylamine (EHA) chains at different positions and examined electron mobility properties.

Self-Sorted, Random, and Block Supramolecular Copolymers via Sequence Controlled, Multicomponent Self-Assembly.

Multicomponent supramolecular copolymerization promises to construct complex nanostructures with emergent properties. However, even with two monomeric components, various possible outcomes such as self-sorted supramolecular homopolymers, a random (statistical) supramolecular copolymer, an alternate supramolecular copolymer, or a complex supramolecular block copolymer can occur, determined by their intermolecular interactions and monomer exchange dynamics and hence structural prediction is extremely challenging. Herein, we target this challenge and demonstrate unprecedented two-component sequence controlled supramolecular copolymerization by manipulating thermodynamic and kinetic routes in the pathway complexity of self-assembly of the constitutive monomers. Extensive molecular dynamics simulations provided useful mechanistic insights into the monomer exchange rates and free energy of interactions between the monomers that dictate the self-assembly pathway and sequence. The fluorescent nature of core-substituted naphthalene diimide monomers has been further utilized to characterize the three sequences via Structured Illumination Microscopy (SIM).

Red-Emitting Delayed Fluorescence and Room Temperature Phosphorescence from Core-Substituted Naphthalene Diimides.

Unprecedented ambient triplet-mediated emission in core-substituted naphthalene diimide (cNDI) derivatives is unveiled via delayed fluorescence and room temperature phosphorescence. Carbazole core-substituted cNDIs, with a donor-acceptor design, showed deep-red triplet emission in solution processable films with high quantum yield. This study, with detailed theoretical calculations and time-resolved emission experiments, enables new design insights into the triplet harvesting of cNDIs; an important family of molecules which has been, otherwise, extensively been investigated for its n-type electronic character and tunable singlet fluorescence.

Water-soluble Cu2+-fluorescent sensor based on core-substituted naphthalene diimide and its application in drinking water analysis and live cell imaging

Water-soluble naphthalene diimide based fluorescent chemosensor, N1, was designed for Cu2+ recognition. The sensor exhibited significant fluorescence modulation and chromogenic change with high Cu2+ sensitivity and selectivity over interfering metal ions. The sensor was able to efficiently monitor Cu2+ in 100% aqueous buffer solution with a low detection limit of 0.7 ppb which is much lower than the recommended value in drinking water by the United States Environmental Protection Agency (U.S. EPA) and the World Health Organization (WHO). The complex formation of N1 with Cu2+ was found to be 1:1 N1-Cu2+ by Job’s plot analysis. Furthermore, the sensor was highly tolerant to interference from a matrix of real samples such as drinking water and human liver carcinoma cell line.

Investigation of cation binding and sensing by new crown ether core substituted naphthalene diimide systems

Different modes of cation binding lead to very different optical readouts from two structurally similar sensors.

Aqueous Phase Phosphorescence: Ambient Triplet Harvesting of Purely Organic Phosphors via Supramolecular Scaffolding

AbstractAmbient 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.

Aqueous Phase Phosphorescence: Ambient Triplet Harvesting of Purely Organic Phosphors via Supramolecular Scaffolding

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.

A dual-function probe based on naphthalene diimide for fluorescent recognition of Hg2+ and colorimetric detection of Cu2+

The core-substituted naphthalene diimide (NDI-6) as a dual-function probe was synthesized conveniently, which can monitor Hg2+ by fluorescent response and serve as a naked-eye detector towards Cu2+. The strong red emission induced by the addition of Hg2+ can be ascribed to the inhibition of the twisted intramolecular charge transfer (TICT) in the excited state, based on the experimental data and theory calculation. Meanwhile, NDI-6 could be used as a reversible fluorescent probe towards Hg2+ with the aid of I− as test strips, which can be applied into the detection of real samples.