ABSTRACT para‐ Quinone Methides ( p ‐QMs) are versatile reactive intermediates widely used in organic synthesis, particularly undergoing 1,6‐Michael addition leading to the formation of complex organic frameworks. Over the years, numerous reactive partners associated with p ‐QMs, such as 2‐hydroxyphenyl‐, o ‐tosylaminophenyl‐, and 1,5‐enyne‐substituted p ‐QMs, have been developed to access the core structures of a broad range of natural products and bioactive molecules. In contrast, p ‐QMs associated with haloarenes, particularly the 2‐bromoaryl‐substituted para ‐quinone methides, have also emerged as valuable synthons in organic synthesis; however, their reactivity and synthetic applications have not been comprehensively summarized. Therefore, this review systematically summarizes recent advances in the synthetic utilities of 2‐bromoaryl‐substituted para ‐quinone methides, with an emphasis on their reactivity under various reaction conditions, mechanistic insights, and substrate scope. Additionally, it summarizes the key transformations enabled by transition‐metal catalysis and highlights their scope for C─C and C‐heteroatom bond construction. Moreover, the future prospects and limitations of 2‐bromoaryl‐substituted para ‐quinone methide are also outlined.
ABSTRACT We report the synthesis of donor–acceptor π‐conjugated polymer composites based on naphthalene diimide (NDI) and diketopyrrolopyrrole (DPP) (DPP‐NDI‐T2/MWCNT) for high‐voltage symmetric supercapacitor applications. DPP‐NDI‐T2 copolymers were synthesized by Stille polymerization and doped with varying loadings of multiwalled carbon nanotube (MWCNT). By varying the NDI:DPP feed ratio from 15 to 50 mol%, three copolymers ( P1 , P2 , and P3 ) were obtained. Polymer P3 was further fabricated into composites containing 20% ( C1 ), 35% ( C2 ), and 50% ( C3 ) MWCNT. These composites exhibited significantly improved conductivity, surface area, and porosity, with the 35% MWCNT composite ( C2 ) delivering a high specific capacitance of 304.2 F g − 1 at 1.0 A g − 1 in a three‐electrode assembly. The symmetric device C2||C2 in 1 M LiClO 4 shows the capacitance of 102.8 F g − 1 at 1.0 A g − 1 with the wide voltage window of 3.0 V (0 to 3 V) and the ultra‐high cycling stability over 100,000 charge–discharge cycles with capacitance retention of 98.4%, high power and energy density of 1500 W kg − 1 and 32.1 Wh kg − 1 , respectively. These results demonstrate the strong potential of conjugated composite polymer for next‐generation high‐performance energy storage devices.
ABSTRACT We report the synthesis of two new thionated benzoperylene imide‐based large rigid π‐systems with tunable optical properties. UV‐Vis absorption and fluorescence spectroscopy studies indicate that thionation significantly improves the absorption in longer wavelengths and quenches fluorescence. Interestingly, these molecules show unusual supramolecular self‐assembly behavior in water‐dioxane solvent mixtures. In dioxane, benzoperylene imides and thioimides exist as monomers and self‐assemble when the water volume percentage is more than 40%. Surprisingly, with less vol% of poor solvent (water) in good solvent, long and crystalline supramolecular self‐assemblies are formed, whereas shorter and amorphous supramolecular self‐assemblies are obtained at higher vol% of water in dioxane. Our investigations reveal the involvement of the nucleation‐elongation mechanism during self‐assembly of benzoperylene imides. Using various spectroscopy and microscopy methods, we found that variations in the kinetics of the nucleation elongation process due to changes in the solvent composition are the major reasons for this unusual behavior.
ABSTRACT Zirconium oxide (ZrO 2 ) nanoparticles and nanocomposites have emerged as multifunctional materials owing to their thermal stability, chemical inertness, high surface activity, tunable polymorphism, biocompatibility, and catalytic performance. These properties make ZrO 2 ‐based nanomaterials attractive for sustainable energy technologies and environmental remediation. However, conventional synthesis routes, including hydrothermal, sol–gel, solvothermal, spray pyrolysis, laser ablation, and arc‐discharge methods, often require hazardous reagents, costly precursors, high temperature and pressure, long reaction times, and complex equipment. Consequently, eco‐friendly synthesis has become an important strategy for producing ZrO 2 nanomaterials with lower environmental impact. This review critically summarizes recent progress in ZrO 2 nanoparticles and nanocomposites, with emphasis on green and plant‐mediated synthesis routes. Plant extracts contain polyphenols, flavonoids, tannins, proteins, amino acids, sugars, and related biomolecules that can serve as reducing, chelating, capping, and stabilizing agents during nanoparticle formation. The review discusses structural features, phase behavior, synthesis strategies, and proposed phytochemical‐assisted formation mechanisms of ZrO 2 based nanomaterials. Recent applications in lithium‐ion batteries, supercapacitors, solar cells, fuel cells, photocatalytic degradation, adsorption, antibacterial treatment, and pollutant removal are critically examined, focusing on ion transport, electrode stability, interfacial charge transfer, catalytic activity, and wastewater treatment performance. Finally, key challenges and future directions are outlined, including mechanistic understanding, reproducibility, scalability, real‐sample validation, toxicity assessment, reusability, and standardized performance evaluation. This review highlights the potential of green ZrO 2 ‐based nanomaterials for sustainable energy and clean‐water technologies.
ABSTRACT Controlled oxidation strategy has enabled the clean transformation of a cross‐conjugated doubly N‐confused porphyrinoid into two hitherto unknown fully (anti)aromatic analogues. Oxidation with chloranil selectively installs carbonyl functionality at the N‐confused pyrrole unit, generating an 18π aromatic macrocycle ( 8 ) that is stable in the free‐base state and structurally authenticated by x‐ray diffraction, while DDQ oxidized tri‐oxo analogue 9 is antiaromatic. The restored π‐conjugation of 8 not only produces characteristic vis–NIR absorption features but also renders the macrocycle competent to stabilize a formally square‐planar Pd(IV) center, affording the organometallic complex 10 in high yield. Porphyrinoid 9 remained unsusceptible to Pd metallation. Detailed spectroscopic characterization, supported by DFT calculations, confirms excellent agreement between experimental and computed structural, electronic, and optical properties. The conversion from a cross‐conjugated porphyrin to an aromatic framework, and its subsequent metalation, demonstrates a robust approach for accessing new N‐confused porphyrinoid architectures with tunable π ‐aromaticity.
