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Abstract: Based on the type of metal or non-metal catalyst used, the authors of this paper have clearly highlighted the different applications of air-stable, commercially viable, and environmentally friendly polymethylhydrosiloxane (PMHS) in organic synthesis or other allied reactions. The importance of PMHS was emphasised for the particular organic transformation's success. In addition to its wellknown use as a reducing agent, it has also been demonstrated in a variety of other applications, including ring cleavage, the cotton industry, functional material for microfluidic chips, and the dehydroaromatization of bio-oils. The article tries to compile the most noteworthy cases of highly successful PMHS catalysis over the past two decades or so.

Zinc chromite (ZnCr2O4)-based nanoparticles have various exceptional properties that make them suitable for use in a variety of fields, including chemistry, medicine, energy, the environment, industry, and information. In this work, nanocrystalline ZnCr2O4 has been effectively synthesized with a distinct fuel by microwave-assisted solution combustion method. The XRD results reveal a single-phase high pure formation of nanoscale ZnCr2O4. The ZnCr2O4 samples are further characterized by scanning electron microscopy, transmission electron microscope, UV–Vis absorption spectroscopy, and vibrating sample magnetometer. The results reveal that modifying the fuel precursors in the combustion technique played an impact on the particle size, bandgap energy, magnetic properties, and reaction time of the ZnCr2O4 preparation. The average particle size of the various samples ranged from 18.6 to 13.9 nm with various fuels. The significance of this study is the tuning effect of optical and magnetic properties of ZnCr2O4 by using various fuel precursors.

Abstract: Since its discovery at the beginning of the 20th century, trifluoroacetic acid, commonly known as TFA, has seen extensive application in organic synthesis both as a solvent and as a catalyst/reagent. TFA can be used to facilitate a wide variety of chemical transformations, including rearrangements, functional group deprotections, condensations, hydroarylations and trifluoroalkylations, among others. The decennial mini-review examines key TFA synthetic applications from the middle of 2013 to the present, providing the organic chemistry research community with an opportunity to delve deeply into the numerous and varied applications of this strong acid, water-miscible, and low boiling point reagent.

Abstract: Among the many zinc salts that can be found, zinc acetate is one of the readily available, affordable, low-hazardous Lewis acids. It can be referred to as a multifunctional catalyst due to its unique physical and chemical properties, which show that they are effective in enabling a variety of synthetic transformations in both organic synthesis and catalysis. This review included noteworthy innovations that have been created during the past two and half decades using zinc acetate as a catalyst or reagent.

Zn(OAc)2•2H2O-catalyzed one-pot multicomponent reaction of Betti bases using β- naphthol, aldehydes, and amines, under neat conditions in moderate to excellent yields (68- 96%) is reported in this study. This synthetic protocol offers several advantages, such as operational simplicity, shorter reaction period, high yields, and easy work-up procedures.

The title compound, C10H10FNO3, also known as [4-((4-fluorophenyl)amino)-4-oxobutanoic acid] (BFAOB), is synthesized efficiently, and its structure is confirmed by the SC-XRD technique, which indicates that two crystallographically different molecules are present in the asymmetric unit. The fluorobenzene ring is oriented at a dihedral angle of 76.09 (9)° and 23.7 (2)° with respect to acetamide moiety in the first and second types of molecule, respectively. A molecular overlay plot is employed to explore the difference between two types of molecules. Strong hydrogen bonding of type N–H…O, O–H…O and comparatively weak hydrogen bonding of type C-H…O stabilize the crystal packing. The titled compound is also characterized by powder XRD. Hirshfeld surface inspection is carried out to explore the non-covalent interactions that are responsible for crystal packing. DFT calculations demonstrate the high stability of BFAOB crystal compound.

The global need for renewable sources of energy has compelled researchers to explore new sources and improve the efficiency of the existing technologies. Solar energy is considered to be one of the best options to resolve climate and energy crises because of its long-term stability and pollution free energy production. Herein, we have synthesized a small acceptor compound (TPDR) and have utilized for rational designing of non-fullerene chromophores (TPD1–TPD6) using end-capped manipulation in A2–A1–D–A1–A2 configuration. The quantum chemical study (DFT/TD-DFT) was used to characterize the effect of end group redistribution through frontier molecular orbital (FMO), optical absorption, reorganization energy, open circuit voltage (Voc), photovoltaic properties and intermolecular charge transfer for the designed compounds. FMO data exhibited that TPD5 had the least ΔE (1.71 eV) with highest maximum absorption (λmax) among all compounds due to the four cyano groups as the end-capped acceptor moieties. The reorganization energies of TPD1–TPD6 hinted at credible electron transportation due to the lower values of λe than λh. Furthermore, open circuit voltage (Voc) values showed similar amplitude for all compounds including parent chromophore, except TPD4 and TPD5 compounds. These designed compounds with unique end group acceptors have the potential to be used as novel fabrication materials for energy devices.

Compounds having nonlinear optical (NLO) characteristics have been proved to have a significant role in many academic and industrial areas; particularly, their leading role in surface interfaces, solid physics, materials, medicine, chemical dynamics, nuclear science, and biophysics is worth mentioning. In the present study, novel peptoids (1–4) were prepared in good yields via Ugi four-component reaction (Ugi-4CR). In addition to synthetic studies, computational calculations were executed to estimate the molecular electrostatic potential, natural bond orbital (NBO), frontier molecular orbital analysis, and NLO properties. The NBO analysis confirmed the stability of studied systems owing to containing intramolecular hydrogen bonding and hyperconjugative interactions. NLO analysis showed that investigated molecules hold noteworthy NLO response as compared to standard compounds that show potential for technology-related applications.

Synthesis of dimeric nitro-substituted imidazolium salts under the conventional/solvent-free method is reported. The solvent-free method is more important than the conventional one because of its shorter reaction time, higher yield from easily available starting material, environmental safety, and so forth. Counter anion exchange is carried out using inorganic salt, which is dissolved in deionized water at room temperature. In antibacterial studies, dimeric nitro-substituted imidazolium cations with bromide counter anions showed excellent inhibition against

Regioselective ortho-halogenation of arylcyanamides using a Pd(II) catalyst has been established under mild reaction conditions. Either electron-donating or electron-withdrawing groups readily carried out the reaction and produced final products in moderate to good yields. Based on the experimental work, we have confirmed that this method does not undergo a free radical mechanism. Furthermore, we have also attempted this method for practical utility purposes.

A new series of coumarin-yl-chalcone derivatives (3a-m) had been designed and synthesized through different reactions such as aromatic addition, cyclization and Claisen-Schmidt reactions in good yields (54-78%). 5-acetyl-4-(2-hydroxyphenyl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (1) has been synthesized by multi-component one pot reaction of salicylaldehyde, methyl acetoacetate and urea, which was further reacted with malonic acid employing ZnCl2 catalyst to yield 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (2). The title compounds (3a-m) were synthesised by reacting 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H)-one (2) with different aromatic aldehydes in the presence of potassium hydroxide. In silico studies, a preliminary screening method for predicting the anti-cancer activity was performed for the synthesized compounds (3a-m) against Src, Alb tyrosine kinase and homology model protein (PDB ID: 4csv). The derivatives 3h and 3m showed moderate binding energies. The in vitro cytotoxic activity was evaluated for the compounds 3h and 3m by using human cancer cell-line morphology and MTT assay against three human cell-lines A549 (Lung), Jurkat (Leukemia) and MCF-7 (Breast). The results indicate that the derivatives 3h and 3m display significant anti-cancer activity, however it was found to be less cytotoxic when compared to the standard used i.e. Imatinib.

An efficient metal-free domino reaction leading to structural/electronically divergent 1,2-dihydropyridines from easily accessible propargyl vinyl anilines via N-phenyl 3-aza-Cope sigmatropic rearrangement is reported with good to excellent yields using 1,2-dichlorobenzene as solvent under thermal conditions. Spirocyclic substitution is also tolerated under the present optimized conditions.

A series of cubic porous perovskites with the general formula BaFe1−xNixO3 have been prepared via the sol-gel-citrate route and investigated as a catalyst for the aerobic oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) using molecular O2 as the oxidant under ambient pressure. Doping and the synergetic interaction between Ni and Fe ions in the BaFeO3 perovskites significantly affected the conversion, product selectivity, specific activity, turnover number, and turnover frequency. A BzH selectivity of >99.9% was achieved in the oxidation of BzOH. Among the prepared perovskites, BaFe0.4Ni0.6O3 showed the highest catalytic conversion and specific activity under the optimized reaction conditions. Based on the catalytic performance, further studies on the recyclability, and influences of temperature and catalyst loading were carried out using this catalyst. The catalyst recyclability test showed a negligible loss in activity after five consecutive cycles. Keywords: Perovskite, Surface area, Molecular oxygen, Benzyl alcohol, Catalytic oxidation

A facile condensation reaction between thiosemicarbazide and furfural was accomplished to synthesize thiosemicarbazone derivatives: TMOH, FMOH, TMEH, FMEH, DCFH and DCMH with good yields as 73%, 70%, 72%,71%, 74% and 74%, respectively. They were characterized by spectroscopic techniques as UV–Vis, FT-IR, 1H and 13CNMR. Furthermore, density functional theory (DFT) analysis was performed by applying M06 level with 6–311G(d,p) basis set for geometry optimization, natural bond orbitals (NBOs), linear and nonlinear optical (NLO) and vibrational analyses. Time-dependent DFT applying M06/6–311G(d,p) level of theory was used for computing frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) and UV–Vis analyses. Experimental values of vibrational wave number and λmax values were seen in good correspondence with the DFT-based results. NBO investigation revealed that title compounds were found with prominent hyper-conjugative interactions having stabilization energies as 57.72, 62.66, 59.95, 58.54, 63.59 and 45.6 kcal/mol, respectively, which are probably the main reasons for their stability. The descending order of Egap was found as DCMH>DCFH>TMOH>TMEH>FMEH>FMOH. Therefore, FMOH, exhibiting the smallest energy gap of 4.416 eV, can be regarded as an efficiently polarized structure, possessing a high capacity for electron transfer. MEP analysis describes the involvement of various reaction sites in chemical reactivity, at different portions of spread electronic cloud over the molecule. The decrease in values of 〈α〉 for title compounds are found as DCFH>DCMH>FMOH>TMOH>FMEH>TMEH. Moreover, βtot values are found with this order DCFH>DCMH>TMOH>TMEH>FMEH>FMOH. It can be seen that DCMH exhibits a larger NLO response with 〈α〉 and βtot figured as 300.51 and 2614.07 a.u., respectively.

Development of novel materials for organic solar cells is a booming area of current research. Fused-ring electron accepters are the potential agents of revolution in organic photovoltaic devices and revealing high efficiency in organic solar cells. This study highlights the novel quad-rotor-shaped molecules as first example of efficient fused-ring non-fullerene acceptor materials with proficient photovoltaic parameters for their utilization in high-performance organic solar cells. First time, eight quad-rotor-shaped fused-ring electron accepters (QRFR-1-QRFR-8) are developed via modulating end-caps of experimentally synthesized (BFTT-TN) molecule (QRFR). Optoelectronic properties of proposed molecules are determined using frontier molecular orbitals (FMO), UV-Visible, density of state (DOS), overlap DOS (ODOS), transition density matrix (TDM) heat maps, open circuit voltage (V

Ethyl 2-(2-arylidene-1-alkylhydrazinyl)thiazole-4-carboxylates (1a-k) were synthesized by alkylation on HN- of ethyl 2-(2-arylidenehydrazinyl)thiazole-4-carboxylates. The proposed structures (1a-k) are corroborated by spectro-analytical techniques like UV, FT-IR

A novel series of conjugates of benzosuberone and 1,2,3-triazole i.e. 3-(4-phenyl-1H-1,2,3-triazol-1-yl)propyl-9-chloro-2,3-dimethyl-6,7-dihydro-5H-benzo[7]annulene-8-carboxylic acids (8a-j) were synthesized in good to excellent yields catalysed by CuSO4 under milder reaction conditions and evaluated for their anti-proliferative activity. The structural elucidation of the prepared compounds was carried out using IR, 1H NMR, 13C NMR and Mass spectral analysis. The newly synthesized derivatives (8a-j) were evaluated for their anti-proliferative activity against four human cell lines and the novel derivatives showed moderate to excellent activity. The obtained results suggest that these compounds can be considered as new hits for anti-proliferative drug development programme and further SAR studies can help obtain better anticancer agents. Keywords: Benzosuberone, Triazole derivative, Anti-proliferative activity, Molecular docking

In the pursuit of graphene-silver nanocomposites, Kigelia Africana stem extract was utilized for the sustainable synthesis of reduced graphene oxide-silver (KARG-Ag) nanocomposite. The UV–Visible spectra exhibited both graphene and Ag peaks at λmax of 268 and 406 nm respectively, Raman spectra exhibited both D and G bands with an ID/IG ratio of 1.21. The XRD spectra showed the graphene peak at 2θ = 26° along with Ag peaks with an average particle size of 21.3 nm. Well stabilized Ag nanoparticles deposited on the transparent KARG sheets were further identified by TEM analysis. Thus, all the spectroscopic techniques proved the synthesis of said nanocomposite. The KARG-Ag nanocomposite (500 μg/mL) showed superior total antioxidant activity (TAA-136) than the standard ascorbic acid (100) or KARG (82) and potential antibacterial activity against four different strains. Hence, the present green method and the potential applications of KARG-Ag nanocomposite may find environmental and clinical applications.

A series of N-alkylated and N-benzylated thiazole-4-carboxylates (3a-n) were prepared via alkylation/benzylation of ethyl 2-(2-(arylidene)hydrazinyl)thiazole-4-carboxylates (1). The structures of all synthesized thiazoles were established with FT-IR, 1H-, 13C-NMR and HRMS spectroscopic techniques. All synthesized compounds were screened as inhibitors of acetylcholinesterase (AChE), using galanthamine as the standard. The AChE activity results revealed, that the compounds ethyl 2-(2-(4-methoxybenzylidene)(benzyl)hydrazinyl)thiazole-4-carboxylate (3n) and ethyl 2-(2-(4-methylbenzylidene)(decyl)hydrazinyl)thiazole-4-carboxylate (3k) were moderate inhibitor with IC50 values 9.56 ± 2.76 and 9.92 ± 0.96 µM, (better than the standard). Simulation studies based on virtual screening of AChE inhibition by molecular docking predicted the binding free energies and molecular inhibition of 3f, 3k and 3n compounds (∆G= -7.73, ∆G= -7.91 and ∆G= -8.13) was comparable with galanthamine. These three compounds occupied the same binding cavity as galanthamine, with greater affinity. Furthermore, in silico, all other compounds also exhibited moderate to good AChE inhibition activities.

Nonlinear optical (NLO) materials are gaining immense scientific attention in recent years due to their applications in diverse domains. An attempt is made for the first time in this study to theoretically design alkali metals (Li, Na, and K) doped 1 N-functionalized corannulene molecules. DFT method is used to investigate their geometric, thermodynamic stability, electronic and NLO properties. The EH-L gap is significantly reduced upto1.17 eV for doped isomers. The highest calculated first hyperpolarizability of the designed complexes is found to be 4.84x104 au. NBO, NCI, TDOS and PDOS analyses are used to confirm the charge transfer, type of the interaction and the participation of different fragments, respectively. TD-DFT calculations show that these molecules are transparent in the UV region and almost all isomers show λmax in the visible region. This novel approach with comparatively higher static first hyperpolarizability values will open up new possibilities for both theoretical and experimental researchers to develop novel NLO materials.

The exploration of novel materials with excellent nonlinear optical (NLO) features is an area of frontline investigation for scientific community from technological point of view. This study reports the novel phenothiazine-based rod-shaped and T-shaped NLO molecules which are quantum chemically designed from synthesized compounds: rod-shaped (CFA and CBA) and T-shaped (CTA, CCA and CPA). Structural tailoring was performed on D-π-π-A centered CPA chromophore and the effect of various π-spacers, as well as solvents on NLO response properties is investigated. Density functional theory (DFT) along with time dependent DFT (TDDFT) calculations have been executed at B3LYP/6-311G(d,p) functional to examine entire analysis. Results showed a smaller energy gap in structurally modified compounds as compared to reference CPA. Global reactivity parameters analysis revealed smaller hardness and larger softness values in T-shaped compounds. UV–Vis analysis of investigated molecules displayed a red shift in absorption maximum value as compared to CPA. Natural bond orbital (NBO) and frontier molecular orbital (FMO) analysis revealed the stability and intra-molecular electron transferring (ICT) process in investigated molecules. ICT showed the effective charge shift from donor to acceptor via π-spacers. Overall, promising NLO response exists in gas phase and different solvents (acetonitrile, ethyl alcohol and water). Interestingly, proposed molecule CPP presented a maximum value of linear polarizability as 1518.23 a.u and first hyperpolarizability (βtot) as 755322.39 a.u in acetonitrile solvent. In short, entitled chromophores exhibited excellent NLO properties due to their lower charge transport resistance. This NLO study may open a new topic for researchers to discover novel NLO for hi-tech submissions of modern era.

Now a days, non-fullerene organic compounds are considered with keen interest for the greener energy and potential photovoltaic devices. Herein, novel acceptor chromophores (DPDVD1-DPDVD4) were designed via small acceptor DPDVR compound with A1-π-A2-π-A1 architecture using promising approach by redistribution of end-capped acceptor moieties. The effect of end-capped acceptor moieties on designed architecture for the photophysical, photovoltaic and electronic behavior was explored using quantum chemical study. Frontier molecular orbital (FMO) findings revealed that all the molecules (DPDVD1-DPDVD4) contained narrow band gaps. The central acceptor moiety (PzDP) was responsible for the transformation of charge in DPDVD1-DPDVD4. UV–Vis data disclosed that λmax values of DPDVD1-DPDVD4 compounds were existed in visible region (537.36–517.05 nm). Interestingly, DPDVD2 exhibited the reduced band gap with broader absorption spectra among all chromophores might be due to the negative inductive effect (−I) of the terminal acceptors. The open circuit voltage (Voc) analysis was performed at the interface between standard donor polymer (PTB7) and DPDVD2. The higher value (3.34 V) of Voc was observed for DPDVD2 among reference and designed compounds. Furthermore, reorganization energy findings exploited DPDVR-DPDVD4 shown lower values of λe than λh which indicated that these chromophores were the promising candidates for electron transportation mobilities. The larger charge mobilities with greater exciton dissociation in excited state for DPDVD2 were examined, subsequently this compound showed minimum value of λe (0.015739 eV) among all chromophores. Detailed studies reveal that the entitled molecules can behave as efficient electron acceptor molecules in organic solar cells (OSCs) that make them interesting candidates for the development of inexpensive optoelectronic devices.

The production of new pyrazole amide derivatives (6a-h) and their potential against New Delhi metallo-β-lactamase-1 (NDM-1) producing bacteria was described in the present manuscript. The 4-bromo-N-(5-methyl-1H-pyrazol-3-yl)benzamide (5) was synthesized via direct amidation of protected 5-methyl-1H-pyrazol-3-amine (3). The target pyrazole amide derivatives (6a-h) were synthesized in moderate to excellent yield via Palladium catalyzed Suzuki cross-coupling of intermediate molecule (5) with different aryl and heteroaryl boronic acids. NMR and Mass Spectrometry were used to characterize the derivatives. The in vitro antibacterial effect against NDM-1-positive Acinetobacter baumannii and Klebsiella pneumoniae of newly synthesized analogues (6a-h) were determined by Agar well diffusion method. Moreover, MIC and MBC values were also evaluated against the tested bacteria. In addition, the Molecular Docking study of pyrazole amide derivatives (6a-h) against the NDM producing A. baumannii was performed to investigate the intermolecular interaction. The binding affinity and their values were compared with L-captopril. The 6b had greatest potential value and was appeared as a promising antibacterial agent.