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Dr. Mohammed Rafi Shaik
King Saud University

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Journal article
Published: 13 July 2021 in Micromachines
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A-π-D-π-A-based small molecules 6,6′-((thiophene-2,5-diylbis(ethyne-2,1-diyl))bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (TDPP-T) and 6,6′-(((2,3-dihydrothieno[3,4-b][1,4]dioxine-5,7-diyl)bis(ethyne-2,1-diyl))bis(thiophene-5,2-diyl))bis(2,5-bis(2-ethylhexyl)-3-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione) (TDPP-EDOT) have been designed and synthesized. The diketopyrrolopyrrole acts as an electron acceptor, while the thiophene or 3,4-ethylenedioxythiophene acts as an electron donor. The donor–acceptor groups are connected by an ethynyl bridge to further enhance the conjugation. The optoelectronics, electrochemical, and thermal properties have been investigated. Organic thin film transistor (OTFT) devices prepared from TDPP-T and TDPP-EDOT have shown p-type mobility. In as cast films, TDPP-T and TDPP-EDOT have shown a hole mobility of 5.44 × 10−6 cm2 V−1 s−1 and 4.13 × 10−6 cm2 V−1 s−1, respectively. The increase in the mobility of TDPP-T and TDPP-EDOT OTFT devices was observed after annealing at 150 °C, after which the mobilities were 3.11 × 10−4 cm2 V−1 s−1 and 2.63 × 10−4 cm2 V−1 s−1, respectively.

ACS Style

Baji Shaik; Mujeeb Khan; Mohammed Shaik; Mohammed Sharaf; Doumbia Sekou; Sang-Gyeong Lee. A-π-D-π-A-Based Small Molecules for OTFTs Containing Diketopyrrolopyrrole as Acceptor Units. Micromachines 2021, 12, 817 .

AMA Style

Baji Shaik, Mujeeb Khan, Mohammed Shaik, Mohammed Sharaf, Doumbia Sekou, Sang-Gyeong Lee. A-π-D-π-A-Based Small Molecules for OTFTs Containing Diketopyrrolopyrrole as Acceptor Units. Micromachines. 2021; 12 (7):817.

Chicago/Turabian Style

Baji Shaik; Mujeeb Khan; Mohammed Shaik; Mohammed Sharaf; Doumbia Sekou; Sang-Gyeong Lee. 2021. "A-π-D-π-A-Based Small Molecules for OTFTs Containing Diketopyrrolopyrrole as Acceptor Units." Micromachines 12, no. 7: 817.

Journal article
Published: 23 June 2021 in Catalysts
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Catalytic efficacy of metal-based catalysts can be significantly enhanced by doping graphene or its derivatives in the catalytic protocol. In continuation of previous work regarding the catalytic properties of highly-reduced graphene oxide (HRG), graphene-oxide (GO) doped mixed metal oxide-based nanocomposites, herein we report a simple, straightforward and solventless mechanochemical preparation of N-doped graphene (NDG)/mixed metal oxide-based nanocomposites of ZnO–MnCO3 (i.e., ZnO–MnCO3/(X%-NDG)), wherein N-doped graphene (NDG) is employed as a dopant. The nanocomposites were prepared by physical milling of separately fabricated NDG and ZnO–MnCO3 calcined at 300 °C through eco-friendly ball mill procedure. The as-obtained samples were characterized via X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), Raman, Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX) and surface area analysis techniques. To explore the effectiveness of the obtained materials, liquid-phase dehydrogenation of benzyl alcohol (BOH) to benzaldehyde (BH) was chosen as a benchmark reaction using eco-friendly oxidant (O2) without adding any harmful surfactants or additives. During the systematic investigation of reaction, it was revealed that the ZnO–MnCO3/NDG catalyst exhibited very distinct specific-activity (80 mmol/h.g) with a 100% BOH conversion and <99% selectivity towards BH in a very short time. The mechanochemically synthesized NDG-based nanocomposite showed remarkable enhancement in the catalytic performance and increased surface area compared with the catalyst without graphene (i.e., ZnO–MnCO3). Under the optimum catalytic conditions, the catalyst successfully transformed various aromatic, heterocyclic, allylic, primary, secondary and aliphatic alcohols to their respective ketones and aldehydes with high selectively and convertibility without over-oxidation to acids. In addition, the ZnO–MnCO3/NDG was also recycled up to six times with no apparent loss in its efficacy.

ACS Style

Mujeeb Khan; Syed Adil; Mohamed Assal; Abdulrahman Alharthi; Mohammed Shaik; Mufsir Kuniyil; Abdulrahman Al-Warthan; Aslam Khan; Zeeshan Nawaz; Hamid Shaikh; Mohammed Siddiqui. Solventless Mechanochemical Fabrication of ZnO–MnCO3/N-Doped Graphene Nanocomposite: Efficacious and Recoverable Catalyst for Selective Aerobic Dehydrogenation of Alcohols under Alkali-Free Conditions. Catalysts 2021, 11, 760 .

AMA Style

Mujeeb Khan, Syed Adil, Mohamed Assal, Abdulrahman Alharthi, Mohammed Shaik, Mufsir Kuniyil, Abdulrahman Al-Warthan, Aslam Khan, Zeeshan Nawaz, Hamid Shaikh, Mohammed Siddiqui. Solventless Mechanochemical Fabrication of ZnO–MnCO3/N-Doped Graphene Nanocomposite: Efficacious and Recoverable Catalyst for Selective Aerobic Dehydrogenation of Alcohols under Alkali-Free Conditions. Catalysts. 2021; 11 (7):760.

Chicago/Turabian Style

Mujeeb Khan; Syed Adil; Mohamed Assal; Abdulrahman Alharthi; Mohammed Shaik; Mufsir Kuniyil; Abdulrahman Al-Warthan; Aslam Khan; Zeeshan Nawaz; Hamid Shaikh; Mohammed Siddiqui. 2021. "Solventless Mechanochemical Fabrication of ZnO–MnCO3/N-Doped Graphene Nanocomposite: Efficacious and Recoverable Catalyst for Selective Aerobic Dehydrogenation of Alcohols under Alkali-Free Conditions." Catalysts 11, no. 7: 760.

Journal article
Published: 23 June 2021 in Polymers
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In this study, we evaluated the morphological behavior of polyurethane elastomers (PUEs) by modifying the soft segment chain length. This was achieved by increasing the soft segment molecular weight (Mn = 400–4000 gmol−1). In this regard, polycaprolactone diol (PCL) was selected as the soft segment, and 4,4′-cyclohexamethylene diisocyanate (H12MDI) and 1,6-hexanediol (HDO) were chosen as the hard segments. The films were prepared by curing polymer on Teflon surfaces. Fourier transform infrared spectroscopy (FTIR) was utilized for functional group identification in the prepared elastomers. FTIR peaks indicated the disappearance of −NCO and −OH groups and the formation of urethane (NHCOO) groups. The morphological behavior of the synthesized polymer samples was also elucidated using scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. The AFM and SEM results indicated that the extent of microphase separation was enhanced by an increase in the molecular weight of PCL. The phase separation and degree of crystallinity of the soft and hard segments were described using X-ray diffraction (XRD). It was observed that the degree of crystallinity of the synthesized polymers increased with an increase in the soft segment’s chain length. To evaluate hydrophilicity/hydrophobicity, the contact angle was measured. A gradual increase in the contact angle with distilled water and diiodomethane (38.6°–54.9°) test liquids was observed. Moreover, the decrease in surface energy (46.95–24.45 mN/m) was also found to be inconsistent by increasing the molecular weight of polyols.

ACS Style

Shazia Naheed; Mohammad Zuber; Mahwish Salman; Nasir Rasool; Zumaira Siddique; Mohammed Shaik; Mohammed Sharaf; Abdelatty Abdelgawad; Doumbia Sekou; Emad Awwad. Impact of Macrodiols on the Morphological Behavior of H12MDI/HDO-Based Polyurethane Elastomer. Polymers 2021, 13, 2060 .

AMA Style

Shazia Naheed, Mohammad Zuber, Mahwish Salman, Nasir Rasool, Zumaira Siddique, Mohammed Shaik, Mohammed Sharaf, Abdelatty Abdelgawad, Doumbia Sekou, Emad Awwad. Impact of Macrodiols on the Morphological Behavior of H12MDI/HDO-Based Polyurethane Elastomer. Polymers. 2021; 13 (13):2060.

Chicago/Turabian Style

Shazia Naheed; Mohammad Zuber; Mahwish Salman; Nasir Rasool; Zumaira Siddique; Mohammed Shaik; Mohammed Sharaf; Abdelatty Abdelgawad; Doumbia Sekou; Emad Awwad. 2021. "Impact of Macrodiols on the Morphological Behavior of H12MDI/HDO-Based Polyurethane Elastomer." Polymers 13, no. 13: 2060.

Research article
Published: 04 June 2021 in ACS Omega
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Graphene nanocomposites have gained significant interest in a variety of biological applications due to their unique properties. Herein, we have studied the apoptosis-inducing ability and anticancer properties of functionalized highly reduced graphene oxide (HRG) and gold nanoparticles (Au NPs)-based nanocomposites (AP-HRG-Au). Samples were prepared under facile conditions via simple stirring and ultrasonication. All the samples were tested for their anticancer properties against different human cancer cell lines including lung (A549), liver (HepG2), and breast (MCF-7) cancer cells using doxorubicin as a positive control. In order to enhance the solubility and bioavailability of the sample, HRG was functionalized with 1-aminopyrene (1-AP) as a stabilizing ligand. The ligand also facilitated the homogeneous growth of Au NPs on the surface of HRG by offering chemically specific binding sites. The synthesis of nanocomposites and the surface functionalization of HRG were confirmed by UV–Vis, powder X-ray diffraction, and Fourier transform infrared spectroscopy. The structure and morphology of the as-prepared nanocomposites were established by high-resolution transmission electron microscopy. Because of the functionalization, the AP-HRG-Au nanocomposite exhibited enhanced physical stability and high dispersibility. A comparative anticancer study of pristine HRG, nonfunctionalized HRG-Au, and 1-AP-functionalized AP-HRG-Au nanocomposites revealed the enhanced apoptosis ability of functionalized nanocomposites compared to the nonfunctionalized sample, whereas the pristine HRG did not show any anticancer ability against all tested cell lines. Both HRG-Au and AP-HRG-Au have induced a concentration-dependent reduction in cell viability in all tested cell lines after 48 h of exposure, with a significantly higher response in MCF-7 cells compared to the remaining cells. Therefore, MCF-7 cells were selected to perform detailed investigations using apoptosis assay, cell cycle analysis, and reactive oxygen species measurements. These results suggest that AP-HRG-Au induces enhanced apoptosis in human breast cancer cells.

ACS Style

Syed Farooq Adil; Mohammed Rafi Shaik; Fahd A. Nasr; Ali S. Alqahtani; Mohammad Z. Ahmed; Wajhul Qamar; Mufsir Kuniyil; Adibah Almutairi; Abdulrahman Alwarthan; Mohammed Rafiq H. Siddiqui; Mohammad Rafe Hatshan; Mujeeb Khan. Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells. ACS Omega 2021, 6, 15147 -15155.

AMA Style

Syed Farooq Adil, Mohammed Rafi Shaik, Fahd A. Nasr, Ali S. Alqahtani, Mohammad Z. Ahmed, Wajhul Qamar, Mufsir Kuniyil, Adibah Almutairi, Abdulrahman Alwarthan, Mohammed Rafiq H. Siddiqui, Mohammad Rafe Hatshan, Mujeeb Khan. Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells. ACS Omega. 2021; 6 (23):15147-15155.

Chicago/Turabian Style

Syed Farooq Adil; Mohammed Rafi Shaik; Fahd A. Nasr; Ali S. Alqahtani; Mohammad Z. Ahmed; Wajhul Qamar; Mufsir Kuniyil; Adibah Almutairi; Abdulrahman Alwarthan; Mohammed Rafiq H. Siddiqui; Mohammad Rafe Hatshan; Mujeeb Khan. 2021. "Enhanced Apoptosis by Functionalized Highly Reduced Graphene Oxide and Gold Nanocomposites in MCF-7 Breast Cancer Cells." ACS Omega 6, no. 23: 15147-15155.

Journal article
Published: 24 May 2021 in Applied Sciences
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Palladium-based carbon catalysts (Pd/C) can be potentially applied as an efficient catalyst for Suzuki–Miyaura and Mizoroki–Heck coupling reactions. Herein, a variety of catalysts of palladium on activated carbon were prepared by varying the content of ‘Pd’ via an in situ reduction method, using hydrogen as a reducing agent. The as-prepared catalysts (0.5 wt % Pd/C, 1 wt % Pd/C, 2 wt % Pd/C and 3 wt % Pd/C) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Brunauer–Emmett–Teller (BET) analyses. The catalysts were tested as a coupling catalyst for Suzuki–Miyaura coupling reactions involving aryl halides and phenyl boronic acid. The optimization of the catalyst by varying the palladium content on the activated carbon yielded Pd/C catalysts with very high catalytic activity for Suzuki reactions of aryl halides and a Mizoroki–Heck cross-coupling reaction of 4-bromoanisol and acrylic acid in an aqueous medium. A high ‘Pd’ content and uniform ‘Pd’ impregnation significantly affected the activity of the catalysts. The catalytic activity of 3% Pd/C was found to make it a more efficient catalyst when compared with the other synthesized Pd/C catalysts. Furthermore, the catalyst reusability was also tested for Suzuki reactions by repeatedly performing the same reaction using the recovered catalyst. The 3% Pd/C catalyst displayed better reusability even after several reactions.

ACS Style

Hamed Alshammari; Obaid Aldosari; Mohammad Alotaibi; Raja Alotaibi; Mosaed Alhumaimess; Moataz Morad; Syed Adil; Mohammed Shaik; Mohammad Islam; Mujeeb Khan; Abdulrahman Alwarthan. Facile Synthesis and Characterization of [email protected] Catalyst for the Suzuki-Miyaura and Mizoroki-Heck Coupling Reactions. Applied Sciences 2021, 11, 4822 .

AMA Style

Hamed Alshammari, Obaid Aldosari, Mohammad Alotaibi, Raja Alotaibi, Mosaed Alhumaimess, Moataz Morad, Syed Adil, Mohammed Shaik, Mohammad Islam, Mujeeb Khan, Abdulrahman Alwarthan. Facile Synthesis and Characterization of [email protected] Catalyst for the Suzuki-Miyaura and Mizoroki-Heck Coupling Reactions. Applied Sciences. 2021; 11 (11):4822.

Chicago/Turabian Style

Hamed Alshammari; Obaid Aldosari; Mohammad Alotaibi; Raja Alotaibi; Mosaed Alhumaimess; Moataz Morad; Syed Adil; Mohammed Shaik; Mohammad Islam; Mujeeb Khan; Abdulrahman Alwarthan. 2021. "Facile Synthesis and Characterization of [email protected] Catalyst for the Suzuki-Miyaura and Mizoroki-Heck Coupling Reactions." Applied Sciences 11, no. 11: 4822.

Research article
Published: 20 April 2021 in Journal of Chemistry
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Polyphenyl is used in a variety of applications including high-vacuum devices, optics, and electronics, and in high-temperature and radiation-resistant fluids and greases, it has low volatility, ionizing radiation stability, and high thermal-oxidative properties. The structure of polyphenyls can be represented using a molecular graph, where atoms represent vertices and bonds between atom edges. In a chemical structure, an item/vertex v resolves two items v 1 and v 2 if d v 1 , v ≠ d v 2 , v ; similarly, the ordered subset ϕ of vertices resolves each pair of distinct vertices named as the resolving set, and its minimum cardinality is described as metric dimension. In the pharmaceutical industry, the competition to find new chemical entities for treating a disease dictates larger project teams that encompass more extensive and diverse synthetic efforts directed at increasingly complicated activity spectra. In this paper, we determine the metric dimension of para-, meta-, and ortho-polyphenyl structures, which are used for structure-activity analysis of these polyphenyl structures.

ACS Style

Muhammad Faisal Nadeem; Mohsan Hassan; Muhammad Azeem; Salah Ud-Din Khan; Mohammed Rafi Shaik; Mohammed A. F. Sharaf; Abdelatty Abdelgawad; Emad Mahrous Awwad. Application of Resolvability Technique to Investigate the Different Polyphenyl Structures for Polymer Industry. Journal of Chemistry 2021, 2021, 1 -8.

AMA Style

Muhammad Faisal Nadeem, Mohsan Hassan, Muhammad Azeem, Salah Ud-Din Khan, Mohammed Rafi Shaik, Mohammed A. F. Sharaf, Abdelatty Abdelgawad, Emad Mahrous Awwad. Application of Resolvability Technique to Investigate the Different Polyphenyl Structures for Polymer Industry. Journal of Chemistry. 2021; 2021 ():1-8.

Chicago/Turabian Style

Muhammad Faisal Nadeem; Mohsan Hassan; Muhammad Azeem; Salah Ud-Din Khan; Mohammed Rafi Shaik; Mohammed A. F. Sharaf; Abdelatty Abdelgawad; Emad Mahrous Awwad. 2021. "Application of Resolvability Technique to Investigate the Different Polyphenyl Structures for Polymer Industry." Journal of Chemistry 2021, no. : 1-8.

Journal article
Published: 29 March 2021 in Metals
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The mixed metal oxides Bi2MoO6 and La-doped Bi2MoO6 were prepared by the sol–gel method. Then, varying quantities of the as-prepared mixed metal oxides were blended with graphene oxide (GO), employing sonication, to obtain Bi2MoO6 /GO (BM/GO) and La-Bi2MoO6 /GO (LBM/GO) nanocomposites. These prepared materials were characterized by different techniques such as thermal gravimetric analysis (TGA), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscopy (TEM). Dielectric properties were studied by using a precision impedance analyzer. Dielectric constant and loss tan of the synthesized composites were studied as a function of frequency by using a precision impedance analyzer. Overall, the dielectric constant (ɛ’) observed for the LBM/GO composites was higher than that of BM/GO.

ACS Style

Syed Adil; Shoomaila Latif; Muhammad Waqar; Muhammad Imran; Sadia Noreen; Mujeeb Khan; Mohammed Shaik; Mohammad Hatshan. Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites. Metals 2021, 11, 559 .

AMA Style

Syed Adil, Shoomaila Latif, Muhammad Waqar, Muhammad Imran, Sadia Noreen, Mujeeb Khan, Mohammed Shaik, Mohammad Hatshan. Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites. Metals. 2021; 11 (4):559.

Chicago/Turabian Style

Syed Adil; Shoomaila Latif; Muhammad Waqar; Muhammad Imran; Sadia Noreen; Mujeeb Khan; Mohammed Shaik; Mohammad Hatshan. 2021. "Dielectric Studies of Bi2MoO6/Graphene Oxide and La-Doped Bi2MoO6/Graphene Oxide Nanocomposites." Metals 11, no. 4: 559.

Journal article
Published: 04 March 2021 in Saudi Journal of Biological Sciences
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Due to their less expensive, environment friendly nature, and their natural abundance of cobalt have attained more significant attention for the synthesis of cobalt nanoparticles. In the present study, we report the facile synthesis of cobalt nanoparticles using a straight forward chemical reduction approach of cobalt chloride with sodium borohydride and capping of sulfadimidine. sulfadimidine has strong capping eligibility on the surface of nanoparticles due to its chemical stability and is an applicable as stabilizer due to the existence of an amine bond. The as-synthesized sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were characterized by using various spectroscopic and microscopic analysis like UV–Visible spectroscopy (UV–Vis), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), High-Resolution Transmission electron microscopy (HR-TEM), and Fourier-transform infrared spectroscopy (FT-IR). The XRD analysis exhibited the triclinic crystal structure of the as-synthesized cobalt nanoparticles and FT-IR analysis confirmed the capping of sulfadimidine via monodentate interaction. The HR-TEM analysis displayed the size of the cobalt nanoparticles approximately 3–5 nm. The antibacterial properties of the sulfadimidine stabilized cobalt nanoparticles (Co-SD NPs) were tested against various bacterial strains such as Klebsiella pneumonia (KP), Escherichia coli (EC) and Pseudomonas syringae (PS) by using agar disc diffusion approach. The results of sulfadimidine capped cobalt nanoparticles displayed the enhanced biological properties against the tested gram-negative bacteria.

ACS Style

U. Nagababu; J.V. Shanmukha Kumar; Mohammed Rafi Shaik; Mohammed A.F. Sharaf. Facile synthesis, physiochemical characterization and bio evaluation of sulfadimidine capped cobalt nanoparticles. Saudi Journal of Biological Sciences 2021, 28, 2168 -2174.

AMA Style

U. Nagababu, J.V. Shanmukha Kumar, Mohammed Rafi Shaik, Mohammed A.F. Sharaf. Facile synthesis, physiochemical characterization and bio evaluation of sulfadimidine capped cobalt nanoparticles. Saudi Journal of Biological Sciences. 2021; 28 (4):2168-2174.

Chicago/Turabian Style

U. Nagababu; J.V. Shanmukha Kumar; Mohammed Rafi Shaik; Mohammed A.F. Sharaf. 2021. "Facile synthesis, physiochemical characterization and bio evaluation of sulfadimidine capped cobalt nanoparticles." Saudi Journal of Biological Sciences 28, no. 4: 2168-2174.

Journal article
Published: 25 February 2021 in Journal of Molecular Structure
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A new unexpected hybrid based on the arylidene-thiazolidinone and 1,3,4-thiadiazole scaffolds via combined S-alkylation and Smiles rearrangement dual protocols. The one-pot reaction of arylidene-thiazolidinone with the hydrazonoyl chloride in a basic medium (Et3N) with benzene as solvent afforded the discovered compound at room temperature (25 °C). The molecular architecture of the designed hybrid were assigned based on the spectrophotometric tools. Based on Hirshfeld analysis, the molecules are connected by short O…H (19.6%), S…H (7.3%), H…C (20.1%), and C…C (0.7%) interactions. Density-functional theory (DFT) calculations indicated polar molecules (7.595 Debye). Its structure is stabilized by different σ-σ*, π→π*, n→σ*, and n→π* intramolecular charge transfer (IMCT) processes. The two longest wavelength bands observed in the UV–Vis spectra of diethyl(S,Z)-2-(2-(5-(4-hydroxybenzylidene)-4-oxo-4,5-dihydrothiazol-2-yl)-2-phenylhydrazinyl)-3-phenyl-2,3-dihydro-1,3,4-thiadiazole-2,5-dicarboxylate 3 were calculated at 364.0 (HOMO→LUMO+1) and 305.1 nm (HOMO-2→LUMO), which considerably agree with the experimental data.

ACS Style

Abdullah Mohammed Al-Majid; Saied M. Soliman; Hazem A. Ghabbour; M. Ali; Mohammad Shahidul Islam; Mohammed Rafi Shaik; Assem Barakat. Synthesis and X-ray crystal structure of unexpected novel thiazolidinone/1,3,4-thiadiazole heterocycle via S-alkylation and Smiles rearrangement dual approaches. Journal of Molecular Structure 2021, 1234, 130156 .

AMA Style

Abdullah Mohammed Al-Majid, Saied M. Soliman, Hazem A. Ghabbour, M. Ali, Mohammad Shahidul Islam, Mohammed Rafi Shaik, Assem Barakat. Synthesis and X-ray crystal structure of unexpected novel thiazolidinone/1,3,4-thiadiazole heterocycle via S-alkylation and Smiles rearrangement dual approaches. Journal of Molecular Structure. 2021; 1234 ():130156.

Chicago/Turabian Style

Abdullah Mohammed Al-Majid; Saied M. Soliman; Hazem A. Ghabbour; M. Ali; Mohammad Shahidul Islam; Mohammed Rafi Shaik; Assem Barakat. 2021. "Synthesis and X-ray crystal structure of unexpected novel thiazolidinone/1,3,4-thiadiazole heterocycle via S-alkylation and Smiles rearrangement dual approaches." Journal of Molecular Structure 1234, no. : 130156.

Journal article
Published: 20 February 2021 in Crystals
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Thiophene and sulfonamide derivatives serve as biologically active compounds, used for the manufacture of large numbers of new drugs. In this study, 11 selected derivatives of thiophene sulfonamide were computed for their geometric parameters, such as hyperpolarizability, chemical hardness (ƞ), electronic chemical potential (μ), electrophilicity index (ω), ionization potential (I), and electron affinity (A). In addition, FT-IR and UV-Vis spectra were also simulated through theoretical calculations. The geometrical parameters and vibrational frequencies with assignments of the vibrational spectra strongly resemble the experimentally calculated values. Besides, the frontier molecular orbitals were also determined for various intramolecular interactions that are responsible for the stability of the compounds. The isodensity surfaces of the frontier molecular orbitals (FMOs) are the same pattern in most of the compounds, but in some compounds are disturbed due to the presence of highly electronegative hetero-atoms. In this series of compounds, 3 shows the highest HOMO–LUMO energy gap and lowest hyperpolarizability, which leads to the most stable compound and less response to nonlinear optical (NLO), while 7 shows the lowest HOMO–LUMO energy gap and highest hyperpolarizability, which leads to a less stable compound and a high NLO response. All compounds have their extended three-dimensional p-electronic delocalization which plays an important role in studying NLO responses.

ACS Style

Adeel Mubarik; Nasir Rasool; Muhammad Hashmi; Asim Mansha; Muhammad Zubair; Mohammed Shaik; Mohammed Sharaf; Emad Awwad; Abdelatty Abdelgawad. Computational Study of Structural, Molecular Orbitals, Optical and Thermodynamic Parameters of Thiophene Sulfonamide Derivatives. Crystals 2021, 11, 211 .

AMA Style

Adeel Mubarik, Nasir Rasool, Muhammad Hashmi, Asim Mansha, Muhammad Zubair, Mohammed Shaik, Mohammed Sharaf, Emad Awwad, Abdelatty Abdelgawad. Computational Study of Structural, Molecular Orbitals, Optical and Thermodynamic Parameters of Thiophene Sulfonamide Derivatives. Crystals. 2021; 11 (2):211.

Chicago/Turabian Style

Adeel Mubarik; Nasir Rasool; Muhammad Hashmi; Asim Mansha; Muhammad Zubair; Mohammed Shaik; Mohammed Sharaf; Emad Awwad; Abdelatty Abdelgawad. 2021. "Computational Study of Structural, Molecular Orbitals, Optical and Thermodynamic Parameters of Thiophene Sulfonamide Derivatives." Crystals 11, no. 2: 211.

Journal article
Published: 18 January 2021 in Coatings
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In the present study, the corrosion inhibition effect of Spilanthes acmella aqueous leaves extract (SA-LE) on mild steel was investigated in 1.0 M HCl solution at different temperature using weight loss, Tafel polarization, linear polarization resistance (LPR), and electrochemical impedance (EIS) measurements. Adsorption of inhibitor on the surface of the mild steel obeyed both Langmuir and Temkin adsorption isotherms. The thermodynamic and kinetic parameters were also calculated to determine the mechanism of corrosion inhibition. The inhibition efficiency was found to increase with an increase in the inhibitor concentration i.e., Spilanthes acmella aqueous leaves extract, however, the inhibition efficiency decreased with an increase in the temperature. The phytochemical constituents with functional groups including electronegative hetero atoms such as N, O, and S in the extract adsorbed on the metal surface are found responsible for the effective performance of the inhibitor, which was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet–visible spectroscopic (UV-Vis) studies. Protective film formation against corrosion was confirmed by scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle studies. The result shows that the leaves extract acts as corrosion inhibitor and is able to promote surface protection by blocking active sites on the metal.

ACS Style

Akbar Ali Samsath Begum; Raja Mohamed Abdul Vahith; Vijay Kotra; Mohammed Rafi Shaik; Abdelatty AbdelGawad; Emad Mahrous Awwad; Mujeeb Khan. Spilanthes acmella Leaves Extract for Corrosion Inhibition in Acid Medium. Coatings 2021, 11, 106 .

AMA Style

Akbar Ali Samsath Begum, Raja Mohamed Abdul Vahith, Vijay Kotra, Mohammed Rafi Shaik, Abdelatty AbdelGawad, Emad Mahrous Awwad, Mujeeb Khan. Spilanthes acmella Leaves Extract for Corrosion Inhibition in Acid Medium. Coatings. 2021; 11 (1):106.

Chicago/Turabian Style

Akbar Ali Samsath Begum; Raja Mohamed Abdul Vahith; Vijay Kotra; Mohammed Rafi Shaik; Abdelatty AbdelGawad; Emad Mahrous Awwad; Mujeeb Khan. 2021. "Spilanthes acmella Leaves Extract for Corrosion Inhibition in Acid Medium." Coatings 11, no. 1: 106.

Journal article
Published: 14 January 2021 in Catalysts
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Degradation of organic dyes and their byproducts by heterogeneous photocatalysts is an essential process, as these dyes can be potentially discharged in wastewater and threaten aquatic and xerophyte life. Therefore, their complete mineralization into nontoxic components (water and salt) is necessary through the process of heterogeneous photocatalysis. In this study, Zr/CrO2 (Zirconium-doped chromium IV oxide) nanocomposite-based photocatalysts with different compositions (1, 3, 5, 7 & 9 wt.%) were prepared by an environmentally friendly, solid-state reaction at room temperature. The as-prepared samples were calcined under air at 450 °C in a furnace for a specific period of time. The synthesis of Zr/CrO2 photocatalysts was confirmed by various techniques, including XRD, SEM, EDX, FT-IR, UV-Vis, and BET. The photocatalytic properties of all samples were tested towards the degradation of methylene blue and methyl orange organic dyes under UV light. The results revealed a concentration-dependent photocatalytic activity of photocatalysts, which increased the amount of dopant (up to 5 wt.%). However, the degradation efficiency of the catalysts decreased upon further increasing the amount of dopant due to the recombination of holes and photoexcited electrons.

ACS Style

Zahir Muhammad; Farman Ali; Muhammad Sajjad; Nisar Ali; Muhammad Bilal; Mohammed Rafi Shaik; Syed Farooq Adil; Mohammed A.F. Sharaf; Emad Mahrous Awwad; Mujeeb Khan. Zirconium-Doped Chromium IV Oxide Nanocomposites: Synthesis, Characterization, and Photocatalysis towards the Degradation of Organic Dyes. Catalysts 2021, 11, 117 .

AMA Style

Zahir Muhammad, Farman Ali, Muhammad Sajjad, Nisar Ali, Muhammad Bilal, Mohammed Rafi Shaik, Syed Farooq Adil, Mohammed A.F. Sharaf, Emad Mahrous Awwad, Mujeeb Khan. Zirconium-Doped Chromium IV Oxide Nanocomposites: Synthesis, Characterization, and Photocatalysis towards the Degradation of Organic Dyes. Catalysts. 2021; 11 (1):117.

Chicago/Turabian Style

Zahir Muhammad; Farman Ali; Muhammad Sajjad; Nisar Ali; Muhammad Bilal; Mohammed Rafi Shaik; Syed Farooq Adil; Mohammed A.F. Sharaf; Emad Mahrous Awwad; Mujeeb Khan. 2021. "Zirconium-Doped Chromium IV Oxide Nanocomposites: Synthesis, Characterization, and Photocatalysis towards the Degradation of Organic Dyes." Catalysts 11, no. 1: 117.

Journal article
Published: 05 November 2020 in Catalysts
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Citronellol is one of the most widely used fragrances for bouquetting purposes and it is a starting material for synthesis of several other terpenoids. Nevertheless, few data have been reported on citronellol selective oxidation. Accordingly, we report our findings on the selective oxidation of citronellol with hydrogen peroxide using a set of titanosilicate catalysts with different morphologies and textural properties—conventional titanium silicalite 1 (TS-1), mesoporous TS-1, layered TS-1 and silica-titania pillared TS-1 and also studying the effect of the solvent used. Epoxidation of C6=C7 double bond was the main primary reaction in this system and trace signals of C5 allylic oxidation products were observed without formation of citronellal. Due to the presence of post-synthesis introduced additional Ti sites, the silica-titania pillared TS-1 (TS-1-PITi) provided the highest conversion among the tested catalysts; nevertheless, citronellol was oxidized over all the studied catalysts including conventional TS-1; therefore, showing that it penetrates even into MFI micropores (0.55 nm in diameter). When using acetonitrile as a solvent, the conversion was proportional to the titanium content of the catalyst. When studying the effect of the solvent, acetonitrile provided the highest epoxide selectivity (55%) while in methanol, 2-propanol and 1,4-dioxane, ring opening reactions caused epoxide decomposition.

ACS Style

Daifallah Aldhayan; Květa Kalíková; Mohammed Rafi Shaik; Mohammed Rafiq H. Siddiqui; Jan Přech. Selective Oxidation of Citronellol over Titanosilicate Catalysts. Catalysts 2020, 10, 1284 .

AMA Style

Daifallah Aldhayan, Květa Kalíková, Mohammed Rafi Shaik, Mohammed Rafiq H. Siddiqui, Jan Přech. Selective Oxidation of Citronellol over Titanosilicate Catalysts. Catalysts. 2020; 10 (11):1284.

Chicago/Turabian Style

Daifallah Aldhayan; Květa Kalíková; Mohammed Rafi Shaik; Mohammed Rafiq H. Siddiqui; Jan Přech. 2020. "Selective Oxidation of Citronellol over Titanosilicate Catalysts." Catalysts 10, no. 11: 1284.

Journal article
Published: 01 October 2020 in Catalysts
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In recent years, the development of green mechanochemical processes for the synthesis of new catalysts with higher catalytic efficacy and selectivity has received manifest interest. In continuation of our previous study, in which graphene oxide (GRO) and highly reduced graphene oxide (HRG) based nanocomposites were prepared and assessed, herein, we have explored a facile and solvent-less mechanochemical approach for the synthesis of N-doped graphene (NDG)/mixed metal oxide (MnCO3–ZrO2) ((X%)NDG/MnCO3–ZrO2), as the (X%)NDG/MnCO3–ZrO2 nano-composite was synthesized using physical grinding of separately synthesized NDG and pre-calcined (300 °C) MnCO3–ZrO2 via green milling method. The structures of the prepared materials were characterized in detail using X-ray powder diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-Ray Analysis (EDX), Fourier-transform infrared spectroscopy (FTIR), Raman, Thermogravimetric analysis (TGA), and N2 adsorption-desorption isotherm analysis. Besides, the obtained nanocomposites were employed as heterogeneous oxidation catalyst for the alcohol oxidation using green oxidant O2 without involving any surfactants or bases. The reaction factors were systematically studied during the oxidation of benzyl alcohol (PhCH2OH) as the model reactant to benzaldehyde (PhCHO). The NDG/MnCO3–ZrO2 exhibits premium specific activity (66.7 mmol·g−1·h−1) with 100% conversion of PhCH2OH and > 99.9% selectivity to PhCHO after only 6 min. The mechanochemically prepared NDG based nanocomposite exhibited notable improvement in the catalytic efficacy as well as the surface area compared to the pristine MnCO3–ZrO2. Under the optimal circumstances, the NDG/MnCO3–ZrO2 catalyst could selectively catalyze the aerobic oxidation of a broad array of alcohols to carbonyls with full convertibility without over-oxidized side products like acids. The NDG/MnCO3–ZrO2 catalyst were efficiently reused for six subsequent recycling reactions with a marginal decline in performance and selectivity.

ACS Style

Mufsir Kuniyil; J. V. Shanmukha Kumar; Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mujeeb Khan; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui; Aslam Khan; Muhammad Bilal; Hafiz M. N. Iqbal; Waheed A. Al-Masry. Eco-Friendly and Solvent-Less Mechanochemical Synthesis of ZrO2–MnCO3/N-Doped Graphene Nanocomposites: A Highly Efficacious Catalyst for Base-Free Aerobic Oxidation of Various Types of Alcohols. Catalysts 2020, 10, 1136 .

AMA Style

Mufsir Kuniyil, J. V. Shanmukha Kumar, Syed Farooq Adil, Mohamed E. Assal, Mohammed Rafi Shaik, Mujeeb Khan, Abdulrahman Al-Warthan, Mohammed Rafiq H. Siddiqui, Aslam Khan, Muhammad Bilal, Hafiz M. N. Iqbal, Waheed A. Al-Masry. Eco-Friendly and Solvent-Less Mechanochemical Synthesis of ZrO2–MnCO3/N-Doped Graphene Nanocomposites: A Highly Efficacious Catalyst for Base-Free Aerobic Oxidation of Various Types of Alcohols. Catalysts. 2020; 10 (10):1136.

Chicago/Turabian Style

Mufsir Kuniyil; J. V. Shanmukha Kumar; Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mujeeb Khan; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui; Aslam Khan; Muhammad Bilal; Hafiz M. N. Iqbal; Waheed A. Al-Masry. 2020. "Eco-Friendly and Solvent-Less Mechanochemical Synthesis of ZrO2–MnCO3/N-Doped Graphene Nanocomposites: A Highly Efficacious Catalyst for Base-Free Aerobic Oxidation of Various Types of Alcohols." Catalysts 10, no. 10: 1136.

Journal article
Published: 20 September 2020 in Nanomaterials
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Plant extract of Pulicaria undulata (L.) was used as both reducing agent and stabilizing ligand for the rapid and green synthesis of gold (Au), silver (Ag), and gold–silver (Au–Ag) bimetallic (phase segregated/alloy) nanoparticles (NPs). These nanoparticles with different morphologies were prepared in two hours by stirring corresponding metal precursors in the aqueous solution of the plant extracts at ambient temperature. To infer the role of concentration of plant extract on the composition and morphology of NPs, we designed two different sets of experiments, namely (i) low concentration (LC) and (ii) high concentration (HC) of plant extract. In the case of using low concentration of the plant extract, irregular shaped Au, Ag, or phase segregated Au–Ag bimetallic NPs were obtained, whereas the use of higher concentrations of the plant extract resulted in the formation of spherical Au, Ag, and Au–Ag alloy NPs. The as-prepared Au, Ag, and Au–Ag bimetallic NPs showed morphology and composition dependent catalytic activity for the reduction of 4-nitrophenol (4-NPh) to 4-aminophenol (4-APh) in the presence of NaBH4. The bimetallic Au–Ag alloy NPs showed the highest catalytic activity compared to all other NPs.

ACS Style

Merajuddin Khan; Khaleel Al-Hamoud; Zainab Liaqat; Mohammed Rafi Shaik; Syed Farooq Adil; Mufsir Kuniyil; Hamad Z. Alkhathlan; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui; Mihail Mondeshki; Wolfgang Tremel; Mujeeb Khan; Muhammad Nawaz Tahir. Synthesis of Au, Ag, and Au–Ag Bimetallic Nanoparticles Using Pulicaria undulata Extract and Their Catalytic Activity for the Reduction of 4-Nitrophenol. Nanomaterials 2020, 10, 1885 .

AMA Style

Merajuddin Khan, Khaleel Al-Hamoud, Zainab Liaqat, Mohammed Rafi Shaik, Syed Farooq Adil, Mufsir Kuniyil, Hamad Z. Alkhathlan, Abdulrahman Al-Warthan, Mohammed Rafiq H. Siddiqui, Mihail Mondeshki, Wolfgang Tremel, Mujeeb Khan, Muhammad Nawaz Tahir. Synthesis of Au, Ag, and Au–Ag Bimetallic Nanoparticles Using Pulicaria undulata Extract and Their Catalytic Activity for the Reduction of 4-Nitrophenol. Nanomaterials. 2020; 10 (9):1885.

Chicago/Turabian Style

Merajuddin Khan; Khaleel Al-Hamoud; Zainab Liaqat; Mohammed Rafi Shaik; Syed Farooq Adil; Mufsir Kuniyil; Hamad Z. Alkhathlan; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui; Mihail Mondeshki; Wolfgang Tremel; Mujeeb Khan; Muhammad Nawaz Tahir. 2020. "Synthesis of Au, Ag, and Au–Ag Bimetallic Nanoparticles Using Pulicaria undulata Extract and Their Catalytic Activity for the Reduction of 4-Nitrophenol." Nanomaterials 10, no. 9: 1885.

Journal article
Published: 10 August 2020 in Symmetry
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The 1,3-dipolar cycloaddition reaction is one of the most rapid, and efficient protocols to access, and construct highly divergent heterocycle chiral auxiliaries. Free catalyst synthesis of spirooxindole scaffold incorporating sulphone moiety via one pot–three component reaction of 6-chloro-isatin, L-proline, and the phenylvinylsulphone as dienophile is presented. The new regioisomer and diastereomer was isolated by precipitation without the tedious purification step, and then characterized via NMR and single crystal X-ray diffraction analysis. Using Hirshfeld analysis, the analysis of molecular packing was performed. It depended mainly on strong O…H and N…H interactions, and weak H…H, C…H, and Cl…H interactions as well. DFT calculations were used to optimize the experimental X-ray structure, which was found well matched with the calculated one. Reactivity descriptors based on the energies of the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbitals were calculated. Additionally, the donor–acceptor interactions which stabilized the system via σ–σ*, π→π*, n→σ* and n→π* electron delocalization processes were also computed using NBO calculations. The net interaction energies are 49.96, 235.38, 179.66 and 107.06 kJ/mol, respectively. Additionally, the calculated NMR chemical shifts correlated well with the experimental data (R2=0.99).

ACS Style

Abdullah Mohammed Al-Majid; Saied M. Soliman; Matti Haukka; M. Ali; Mohammad Shahidul Islam; Mohammed Rafi Shaik; Assem Barakat. Design, Construction, and Characterization of a New Regioisomer and Diastereomer Material Based on the Spirooxindole Scaffold Incorporating a Sulphone Function. Symmetry 2020, 12, 1337 .

AMA Style

Abdullah Mohammed Al-Majid, Saied M. Soliman, Matti Haukka, M. Ali, Mohammad Shahidul Islam, Mohammed Rafi Shaik, Assem Barakat. Design, Construction, and Characterization of a New Regioisomer and Diastereomer Material Based on the Spirooxindole Scaffold Incorporating a Sulphone Function. Symmetry. 2020; 12 (8):1337.

Chicago/Turabian Style

Abdullah Mohammed Al-Majid; Saied M. Soliman; Matti Haukka; M. Ali; Mohammad Shahidul Islam; Mohammed Rafi Shaik; Assem Barakat. 2020. "Design, Construction, and Characterization of a New Regioisomer and Diastereomer Material Based on the Spirooxindole Scaffold Incorporating a Sulphone Function." Symmetry 12, no. 8: 1337.

Journal article
Published: 01 August 2020 in Processes
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CoxOy–manganese carbonate (X%)(CoxOy–MnCO3 catalysts (X = 1–7)) were synthesized via a straightforward co-precipitation strategy followed by calcination at 300 °C. Upon calcination at 500 °C, these were transformed to CoxOy–dimanganese trioxide i.e., (X%)CoxOy–Mn2O3. A relative catalytic evaluation was conducted to compare the catalytic efficiency of the two prepared catalysts for aerial oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) using O2 molecule as a clean oxidant without utilizing any additives or alkalis. Amongst the different percentages of doping with CoxOy (0–7% wt./wt.) on MnCO3 support, the (1%)CoxOy–MnCO3 catalyst exhibited the highest catalytic activity. The influence of catalyst loading, calcination temperature, reaction time, and temperature and catalyst dosage was thoroughly assessed to find the optimum conditions of oxidation of benzyl alcohol (BzOH) for getting the highest catalytic efficiency. The (1%)CoxOy–MnCO3 catalyst which calcined at 300 °C displayed the best effectiveness and possessed the largest specific surface area i.e., 108.4 m2/g, which suggested that the calcination process and specific surface area play a vital role in this transformation. A 100% conversion of BzOH along with BzH selectivity >99% was achieved after just 20 min. Notably, the attained specific activity was found to be considerably larger than the previously-reported cobalt-containing catalysts for this transformation. The scope of this oxidation reaction was expanded to various alcohols containing aromatic, aliphatic, allylic, and heterocyclic alcohols without any further oxidation i.e., carboxylic acid formation. The scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) specific surface area analytical techniques were used to characterize the prepared catalysts. The obtained catalyst could be easily regenerated and reused for six consecutive runs without substantial decline in its efficiency.

ACS Style

Osamah Alduhaish; Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mufsir Kuniyil; Khalid M. Manqari; Doumbia Sekou; Mujeeb Khan; Aslam Khan; Ahmed Z. Dewidar; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui. Synthesis and Characterization of CoxOy–MnCO3 and CoxOy–Mn2O3 Catalysts: A Comparative Catalytic Assessment Towards the Aerial Oxidation of Various Kinds of Alcohols. Processes 2020, 8, 910 .

AMA Style

Osamah Alduhaish, Syed Farooq Adil, Mohamed E. Assal, Mohammed Rafi Shaik, Mufsir Kuniyil, Khalid M. Manqari, Doumbia Sekou, Mujeeb Khan, Aslam Khan, Ahmed Z. Dewidar, Abdulrahman Al-Warthan, Mohammed Rafiq H. Siddiqui. Synthesis and Characterization of CoxOy–MnCO3 and CoxOy–Mn2O3 Catalysts: A Comparative Catalytic Assessment Towards the Aerial Oxidation of Various Kinds of Alcohols. Processes. 2020; 8 (8):910.

Chicago/Turabian Style

Osamah Alduhaish; Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mufsir Kuniyil; Khalid M. Manqari; Doumbia Sekou; Mujeeb Khan; Aslam Khan; Ahmed Z. Dewidar; Abdulrahman Al-Warthan; Mohammed Rafiq H. Siddiqui. 2020. "Synthesis and Characterization of CoxOy–MnCO3 and CoxOy–Mn2O3 Catalysts: A Comparative Catalytic Assessment Towards the Aerial Oxidation of Various Kinds of Alcohols." Processes 8, no. 8: 910.

Preprint content
Published: 04 July 2020
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In this study, we reported the eco-friendly fabrication of Ag2O–MnO2/GRO nanocomposites by the solid-state mixing of separately prepared GRO and Ag2O–MnO2 NPs using ball milling method, a mechanochemical approach. The prepared material was studied for the catalytic effect of GRO in the system for the aerial oxidation of a variety of alcohols. It was found that the (1%)Ag2O–MnO2/(5 wt.%)GRO nanocatalyst demonstrated a high conversion ability (~100%) and excellent selectivity in the presence of O2 as a clean oxidant. The higher catalytic properties of the nanocomposite were attributed to the presence of GRO, which exhibited extraordinary catalytic properties like improved surface area, excellent chemical compatibility, and stability, as well as the introduction of several defects in the obtained nanocomposite that enhance the catalytic performance. The specific activity of 13.3 mmol·g−1·h−1 is obtained for the catalyst i.e. (1%)Ag2O–MnO2/(5 wt.%)GRO, which is reportedly superior to the various other catalysts previously reported in the literature for the same conversion reaction. Our catalytic strategy was highly selective, producing only desired products with no over-oxygenation to carboxylic acids. The merits of our catalytic methodology were: (a) facile process, (b) inexpensive and clean oxidant, (c) no surfactants or nitrogenous bases were required, (d) mild catalytic conditions, (e) cost-effective recoverable catalyst, (f) complete convertibility, (g) full selectivity, (h) rapid process, and (i) applicable to virtually all types of alcohols. So, these highlights made this catalytic strategy to be highly applicable in the industrial applications for manufacturing of carbonyls. To the best of our knowledge, this was the first study of utilizing Ag2O–MnO2/GRO composite as a catalyst for the oxidation of alcohols, highlighting the catalytic efficiency of GRO.

ACS Style

Syed Adil; Mujeeb Khan; Mohammed Rafi Shaik; Mufsir Kuniyil; M Rafiq Siddiqui; Abdulrahman Alwarthan. Ag2O–MnO2/Graphene Oxide Nanocomposite. 2020, 1 .

AMA Style

Syed Adil, Mujeeb Khan, Mohammed Rafi Shaik, Mufsir Kuniyil, M Rafiq Siddiqui, Abdulrahman Alwarthan. Ag2O–MnO2/Graphene Oxide Nanocomposite. . 2020; ():1.

Chicago/Turabian Style

Syed Adil; Mujeeb Khan; Mohammed Rafi Shaik; Mufsir Kuniyil; M Rafiq Siddiqui; Abdulrahman Alwarthan. 2020. "Ag2O–MnO2/Graphene Oxide Nanocomposite." , no. : 1.

Full paper
Published: 04 June 2020 in Applied Organometallic Chemistry
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Graphene–metal nanocomposites have been found to remarkably enhance the catalytic performance of metal nanoparticle‐based catalysts. In continuation of our previous report, in which highly reduced graphene oxide (HRG)‐based nanocomposites were synthesized and evaluated, we present nanocomposites of graphene oxide (GRO) and ZnO nanoparticle‐doped MnCO3 ([ZnO–MnCO3/(1%)GRO]) synthesized via a facile, straightforward co‐precipitation technique. Interestingly, it was noticed that the incorporation of GRO in the catalytic system could noticeably improve the catalytic efficiency compared to a catalyst (ZnO–MnCO3) without GRO, for aerial oxidation of benzyl alcohol (BzOH) employing O2 as a nature‐friendly oxidant under base‐free conditions. The impacts of various reaction factors were thoroughly explored to optimize reaction conditions using oxidation of BzOH to benzaldehyde (BzH) as a model substrate. The catalysts were characterized using X‐ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, field‐emission scanning electron microscopy, Energy dispersive X‐ray spectroscopy (EDX), Brunauer‐Emmett‐Teller (BET), and Raman spectroscopy. The (1%)ZnO–MnCO3/(1%)GRO exhibited significant specific activity (67 mmol.g−1.hr−1) with full convversion of BzOH and >99% BzH selectivity within just 6 min. The catalytic efficiency of the (1%)ZnO–MnCO3/(1%)GRO nanocomposite was significantly better than the (1%)ZnO–MnCO3/(1%)HRG and (1%)ZnO–MnCO3 catalysts, presumably due to the existence of oxygen‐possessing groups on the GRO surface and as well as a very high surface area that could have been instrumental in uniformly dispersing the active sites of the catalyst, i.e., ZnO–MnCO3. Under optimum circumstances, various kinds of alcohols were selectively transformed to respective carbonyls with full convertibility over the (1%)ZnO–MnCO3/(1%)GRO catalyst. Furthermore, the highly effective (1%)ZnO–MnCO3/(1%)GRO catalyst could be successfully reused and recycled over five consecutive runs with a marginal reduction in its performance and selectivity.

ACS Style

Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mufsir Kuniyil; Azhar Hashmi; Mujeeb Khan; Aslam Khan; Muhammad Nawaz Tahir; Abdulrahman Al‐Warthan; Mohammed Rafiq H. Siddiqui. Efficient aerial oxidation of different types of alcohols using ZnO nanoparticle–MnCO 3 ‐graphene oxide composites. Applied Organometallic Chemistry 2020, 34, 1 .

AMA Style

Syed Farooq Adil, Mohamed E. Assal, Mohammed Rafi Shaik, Mufsir Kuniyil, Azhar Hashmi, Mujeeb Khan, Aslam Khan, Muhammad Nawaz Tahir, Abdulrahman Al‐Warthan, Mohammed Rafiq H. Siddiqui. Efficient aerial oxidation of different types of alcohols using ZnO nanoparticle–MnCO 3 ‐graphene oxide composites. Applied Organometallic Chemistry. 2020; 34 (8):1.

Chicago/Turabian Style

Syed Farooq Adil; Mohamed E. Assal; Mohammed Rafi Shaik; Mufsir Kuniyil; Azhar Hashmi; Mujeeb Khan; Aslam Khan; Muhammad Nawaz Tahir; Abdulrahman Al‐Warthan; Mohammed Rafiq H. Siddiqui. 2020. "Efficient aerial oxidation of different types of alcohols using ZnO nanoparticle–MnCO 3 ‐graphene oxide composites." Applied Organometallic Chemistry 34, no. 8: 1.

Journal article
Published: 29 May 2020 in Applied Sciences
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A series of 3-aryl indazoles and 1-methyl-3-aryl indazole derivatives are prepared with exceptional yields by coupling with several arylboronic acids and methylation by two dissimilar approaches. The as-prepared indazole derivatives (3a–3j) and their N-methyl derivatives (5a–5j) are evaluated for in vitro anticancer activity against two cancer cell lines, HCT-116 and MDA-MB-231. The results reveal that the indazole derivatives tested display mild to moderate anticancer activities against the cell lines tested.

ACS Style

Jagan Mohana Rao Saketi; S. N. Murthy Boddapati; Raghuram M.; Syed Farooq Adil; Mohammed Rafi Shaik; Osamah Alduhaish; Mohammed Rafiq H. Siddiqui; Hari Babu Bollikolla. Pd(PPh3)4 Catalyzed Synthesis of Indazole Derivatives as Potent Anticancer Drug. Applied Sciences 2020, 10, 3792 .

AMA Style

Jagan Mohana Rao Saketi, S. N. Murthy Boddapati, Raghuram M., Syed Farooq Adil, Mohammed Rafi Shaik, Osamah Alduhaish, Mohammed Rafiq H. Siddiqui, Hari Babu Bollikolla. Pd(PPh3)4 Catalyzed Synthesis of Indazole Derivatives as Potent Anticancer Drug. Applied Sciences. 2020; 10 (11):3792.

Chicago/Turabian Style

Jagan Mohana Rao Saketi; S. N. Murthy Boddapati; Raghuram M.; Syed Farooq Adil; Mohammed Rafi Shaik; Osamah Alduhaish; Mohammed Rafiq H. Siddiqui; Hari Babu Bollikolla. 2020. "Pd(PPh3)4 Catalyzed Synthesis of Indazole Derivatives as Potent Anticancer Drug." Applied Sciences 10, no. 11: 3792.