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A solvent‐free sulfur‐bridge‐eosin‐Y (SBE‐Y) polymeric framework photocatalyst was prepared for the first time through an in situ thermal polymerization route using elemental sulfur (S8) as a bridge. The addition of a sulfur bridge to the polymeric framework structure resulted in an allowance of the harvesting range of eosin‐Y (E‐Y) for solar light. This shows that a wider range of solar light can be used by the bridge material's photocatalytic reactions. In this context, supercharged solar spectrum: enhancing light absorption and hole oxidation with sulfur bridges. This suggests that the excited electrons and holes through solar light can contribute to oxidation–reduction reactions more potently. As a result, the photocatalyst‐enzyme attached artificial photosynthesis system developed using SBE‐Y as a photocatalyst performs exceptionally well, resulting in high 1,4‐NADH regeneration (86.81%), followed by its utilization in the exclusive production of formic acid (210.01 μmol) from CO2 and synthesis of fine chemicals with 99.9% conversion yields. The creation of more effective photocatalytic materials for environmental clean‐up and other applications that depend on the solar light‐driven absorption spectrum of inorganic and organic molecules could be one of the practical ramifications of this research. [ABSTRACT FROM AUTHOR]

The photocatalytic oxidation and generation/regeneration of amines to imines and leucodopaminechrome (LDC)/NADH are subjects of intense interest in contemporary research. Imines serve as crucial intermediates for the synthesis of solar fuels, fine chemicals, agricultural chemicals, and pharmaceuticals. While significant progress has been made in developing efficient processes for the oxidation and generation/regeneration of secondary amines, the oxidation of primary amines has received comparatively less attention until recently. This discrepancy can be attributed to the high reactivity of imines generated from primary amines, which are prone to dehydrogenation into nitriles. In this study, we present the synthesis and characterization of a novel polymer‐based photocatalyst, denoted as PMMA‐DNH, designed for solar light‐harvesting applications. PMMA‐DNH incorporates the light‐harvesting molecule dinitrophenyl hydrazine (DNH) at varying concentrations (5%, 10%, 20%, 30%, and 40%). Leveraging its high molar extinction coefficient and slow charge recombination, the 30% DNH‐incorporated PMMA photocatalyst proves to be particularly efficient. This photocatalytic system demonstrates exceptional yields (96.5%) in imine production and high generation/regeneration rates for LDC/NADH (65.27%/78.77%). The research presented herein emphasizes the development and application of a newly engineered polymer‐based photocatalyst, which holds significant promise for direct solar‐assisted chemical synthesis in diverse commercial applications. [ABSTRACT FROM AUTHOR]

Photocatalytic processes triggered by graphene‐based photocatalysts under solar light have sparked interest as a new sort of instrument for solar chemical synthesis. Herein we investigated self‐assembled graphene quantum dots (GQDs)/NiSe‐NiO composite photocatalyst for organic transformation as well as dye degradation. The synthesized GQDs/NiSe‐NiO composite photocatalyst has an excellent suitable band gap, high molar extinction coefficient, low toxicity and chemical/thermal stability. The GQDs/NiSe‐NiO composite photocatalyst emerges as a new standard for sulfur oxidation and dye degradation reactions under homemade LED light with high yield. [ABSTRACT FROM AUTHOR]

This manuscript emphasizes how structural assembling can facilitate the generation of solar chemicals and the synthesis of fine chemicals under solar light, which is a challenging task via a photocatalytic pathway. Solar energy utilization for pollution prevention through the reduction of organic chemicals is one of the most challenging tasks. In this field, a metal-based photocatalyst is an optional technique but has some drawbacks, such as low efficiency, a toxic nature, poor yield of photocatalytic products, and it is expensive. A metal-free activated carbon cloth (ACC)–templated photocatalyst is an alternative path to minimize these drawbacks. Herein, we design the synthesis and development of a metal-free self-assembled eriochrome cyanine R (EC-R) based ACC photocatalyst (EC-R@ACC), which has a higher molar extinction coefficient and an appropriate optical band gap in the visible region. The EC-R@ACC photocatalyst functions in a highly effective manner for the photocatalytic reduction of 4-nitro benzyl alcohol (4-NBA) into 4-amino benzyl alcohol (4-ABA) with a yield of 96% in 12 h. The synthesized EC-R@ACC photocatalyst also regenerates reduced forms of nicotinamide adenine dinucleotide (NADH) cofactor with a yield of 76.9% in 2 h. The calculated turnover number (TON) of the EC-R@ACC photocatalyst for the reduction of 4-nitrobenzyl alcohol is 1.769 × 1019 molecules. The present research sets a new benchmark example in the area of organic transformation and artificial photocatalysis. [ABSTRACT FROM AUTHOR]

• Easy to make graphene-based visible light active photocatalyst (N en G-RhB) via condensation. • The N en G-RhB photocatalyst appears to be a noteworthy development, demonstrating its efficiency in the degradation of industrial orange g in the presence of solar light as well as the oxidative cyclization of aromatic thioamide. • Its potential for useful applications in solar-driven catalysis and environmental remediation is shown by the remarkable degradation efficiency of 97.29 % for the industrial dye and a high conversion rate of 92.5 % for the cyclization. This may open the door to more eco-friendly and productive procedures across a range of sectors. Functionalized photocatalysts have shown to be an effective method for oxidative cyclization processes and the degradation of organic poisons like chemicals and dyes. In this study, we report the facile, environmentally friendly, room-temperature (RT) synthesis and development of a graphene-based visible light active photocatalyst (NenG-RhB) which is thermodynamically converted to nitrogen-enriched graphene (NenG) covalently bonded to a light-harvesting RhB molecule [9-(2-Carboxyphenyl)-6-(diethylamino)-N, N‑diethyl-3H-xanthen-3-iminium chloride)]. The NenG-RhB photocatalyst is extremely effective, resulting in good oxidative cyclization of aromatic thioamide (92.5 %) and degradation efficiency of industrial orange G (97.29 %) under solar light. The current research focuses on the invention and implementation of a nitrogen-enrich graphene-based photocatalyst for direct solar medicinal chemical synthesis and industrial dye degradation in wastewater using solar light. [ABSTRACT FROM AUTHOR]

The dimethyl sulfite as an alkylating as well as alkoxylating reagent is well known in synthetic organic as well as organometallic chemistry for a long time. Herein, we have utilized dimethyl sulfite as an alkylating reagent and reacted with fluorescein derivative, N‐fluorescein‐lactam‐hydrazine (B). This reaction leads to the generation of tetramethylated fluorescein lactam hydrazine (A). The newly designed and synthesized molecule (A) has been characterized by 1H, 13C NMR and HRMS data. The antimicrobial activity of the synthesized alkylated fluorescein derivative has been tested against E. coli, P. aeruginosa, Salmonella typhimurium and S. aureus microbial agents. Time‐kill assay results also confirmed that fluorescein derivative is a potent antimicrobial agent and revealed that the time‐kill assay of fluorescein derivative is value‐added than the well‐known antibiotic. In addition, quantum chemical study was used to analyze its activity trend and correlated with the experimental data. The computed results of DFT revealed that the lipophilicity as well as the LUMO‐HOMO band gap (ΔELUMO‐HOMO = 4.75 eV) of compound A make it more suitable as an antimicrobial agent to match with in vitro antimicrobial experimental results. The MIC and MBC values of compound A were observed to be lower in contrast to fluorescein and ampicillin for all the tested bacterial strains, which were approximately 3‐ to 4‐fold lower than MIC and MBC values of the later. Results obtained from the study clearly indicate that compound A has better antimicrobial and bactericidal activity in comparison to ampicillin and fluorescein. Synthesized compound can be a better substitute of traditionally used antibiotics, Ampicillin. [ABSTRACT FROM AUTHOR]

A global challenge faced by light harvesting photocatalyst is how to promote the selective organic transformation, such as C‐S bond formation via radical–radical coupling under solar light. Here, we report a two‐dimensional covalent organic frameworks (2D‐COFs), poly (perylene‐imide‐benzoquinone) nanorod through in situ condensation on flexible activated carbon cloth (PPIBNR‐FACC) to function as a light harvester material for highly selective radical–radical coupling to vinyl sulfides (i.e. C‐S bond activation). Such a structure supports charge transfer from PPIBNR to FACC, which is essential for the selective radical–radical coupling. Hence, organic transformation is attaining high yields and selectivity (˜99%) under solar light using in situ prepared PPIBNR‐FACC photocatalyst. The structural virtues of PPIBNR‐FACC will trigger the utmost investigations into designable and versatile 2D‐COFs for fine chemical synthesis. [ABSTRACT FROM AUTHOR]

Selective radical‐radical coupling of terminal alkynes and thiol has been broadly used in chemical synthesis, providing plausible entries to the formation of anti‐Markovnikov products. Because of the selective control and Kharasch effect, the formation of Markovnikov products still remains an immense challenge. Herein, we designed a covalent organic polymer, poly(naphthalene 1,4,5,8‐tetracarboxylic dianhydrideimide‐benzoquinone) through in situ polymerization on activated flexible carbon cloth to function as a light harvester material for selective Markovnikov radical‐radical coupling of terminal alkynes and thiol. Mechanistic explorations verified that cross‐coupling between radical of terminal alkynes and thiol might be the key route in this organic transformation, such as C—S bond formation. This selective radical‐radical Markovnikov of cross‐coupling protocol provide an opportunity to assist the synthesis of valuable vinyl sulfide. Additionally, the synthesized material has been explored as liquefied petroleum gas (LPG) sensor for 0.5, 1.0, 1.5, and 2.0 vol% LPG, respectively. At 2.0 vol% LPG, it shows maximum sensor response as 635.29. Least response and recovery times are 2.44 and 1.0 s, respectively. [ABSTRACT FROM AUTHOR]

Summary: Development of ecofriendly and low‐cost highly efficient photocatalysis is of importance in the field of chemical synthesis. Currently, various metals‐based organic materials, metal oxide nanoparticles, and metal nanomaterials have been urbanized as light harvesting photocatalysts for direct carbon (C)‐hydrogen (H) arylation of aryl diazonium salts and heteroarenes. These light harvesting photocatalysts, however, still suffer from poor stability, reusability problem, high cost, or less selectivity. Herein, we report the fabrication of a novel chitosan‐based fluorescein isothiocyanate (CBFITC) film photocatalyst and demonstrate its tremendous photocatalytic activity, high yields (97 ± 0.015%), selectivity (99%), and reusability to catalyze the metal free solar‐light‐mediated direct CH arylation of aryl diazonium salts and heteroarenes at ambient temperature. Moreover, CBFITC film photocatalyst can be recycled more than five times without loss of activity, verifying this photocatalyst excellent light harvesting ability and stability. The present approach to fabricate a metal‐free film photocatalyst with the suitable band gap will be a new platform for efficient photocatalytic reaction and provide a new insight into the solar chemical synthesis. [ABSTRACT FROM AUTHOR]