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Fluorescent molecules are extensively employed in (bio)sensing and bioimaging but their applications in the visualization of fingerprints are less reported due to their inherited aggregation-caused quenching (ACQ) mechanism in the solid state (aggregated form). DPSA undergoes self-assembly to form aggregates with rod-like structures in a 90% H2O : CH3CN mixture evident from dynamic light scattering (DLS) and scanning electron microscopic (SEM) techniques. The self-assembled diphenylpyrimidinone (DPSA) derivative shows aggregation-induced emission (∼24 fold) in a ＞90% H2O : CH3CN mixture with orange-red fluorescence (λmax 564 nm). The red fluorescent aggregates of DPSA show applications in the visualization of latent fingerprints on aluminium, stainless steel and metal currency coin substrates. In addition, we established the individuality of three subjects based on information gathered at level one (pattern of arch, loop or whorl) and level two (minutiae details of dots, bifurcation, ridge ending, core and delta). [ABSTRACT FROM AUTHOR]

Control over the self-assembly of bay functionalized perylene diimides and the response of these self-assembled materials towards analytes in mixed aqueous–organic media is important to consider the potential of this intriguing dye family in supramolecular chemistry. Herein, we have designed and synthesized allylcarbonate-functionalized perylene diimide AC-PDI which shows solvent dependent supramolecular nanostructures and could readily self-assemble into nanorods of tens of μm in length in CH3CN, but the length of the rods drammatically decreased to 0.8–1.2 μm in a H2O : CH3CN (1 : 1, v/v) mixture. Interestingly, AC-PDI self-assembles into nanowires of several tens of μm in length in a 30% H2O:DMSO mixture and forms only nanospheres in ethyl acetate. AC-PDI can be used as a near-infrared (NIR) colorimetric (λabs 685 nm) and fluorescent (λem 530/570 nm) probe for selective detection of Pd0 [LOD = 39 nM (UV); 45 nM (FI)]. Furthemore, TLC strips coated with the AC-PDI probe could detect 0.58 pg cm−2 of Pd0 in the solid state. The mechanism of interaction of AC-PDI with Pd0 has been confirmed by 1H NMR titration, kinetic and morphological studies. [ABSTRACT FROM AUTHOR]

In this work, we have designed and synthesized a perylene diimide based derivative PDI-SiHQ having an O-silylated-8-hydroxyquinoline group at the bay position. PDI-SiHQ is able to detect and differentiate CN− from F− in the presence of other anions. The electron transfer from cyanide ions to PDI-SiHQ leads to the emergence of panchromatic and NIR absorption bands due to the formation of a PDI-SiHQṖ− radical anion. In contrast, fluoride induced desilylation of PDI-SiHQ coupled with π–π aggregation results in a red-shifted absorption band at 730 nm. 1H NMR and cyclic voltammetry combined with the reversal of the PDI-SiHQṖ− radical anion to the PDI-SiHQ neutral form in the presence of NOBF4 or Cu2+ ions confirm the formation of the radical anion in PDI-SiHQ. Multi-channel UV-Vis-NIR absorption and emission bands and their reversibility with NOBF4/Cu2+ ions offer the possibility for fabrication of complex logic circuits such as complementary IMP/INH logic circuits, magnitude comparators and ‘set–reset’ flip flop memory elements. [ABSTRACT FROM AUTHOR]

The manuscript describes a facile and highly diastereoselective synthesis of cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones via copper(i) mediated Kinugasa reactions of previously unexplored functionalized α,β-unsaturated nitrones. A variety of functionalized acetylenes and α,β-unsaturated nitrones were studied to yield cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones in good yields (82%). [ABSTRACT FROM AUTHOR]