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Synthesis of α,β-unsaturated-γ-lactams continue to attract attention due to the importance of this structural motif in organic chemistry. Herein, we report the development of a visible-light-induced excited-state copper-catalyzed [4 + 1] annulation reaction for the preparation of a wide range of γ-H, -OH, and -OR-substituted α,β-unsaturated-γ-lactams using acrylamides as the 4-atom unit and aroyl chlorides as the 1-atom unit. This modular synthetic protocol features mild reaction conditions, broad substrate scope, and high functional group tolerance. The reaction is amenable to late-stage diversification of complex molecular architectures, including derivatives of marketed drugs. The products of the reaction can serve as versatile building blocks for further derivatization. Preliminary mechanistic studies suggest an inner-sphere catalytic cycle involving photoexcitation of the Cu(BINAP) catalyst, single-electron transfer, and capture of radical intermediates by copper species, followed by reductive elimination or protonation to give the desired γ-functionalized α,β-unsaturated-γ-lactams.

Colorectal cancer (CRC) has been reported as the second leading cause of cancer death worldwide. The 5-year annual survival is around 50%, mainly due to late diagnosis, striking necessity for early detection. This study aims to identify autoantibody in patients' sera for early screening of cancer.The study used a high-density human proteome array with approximately 17,000 recombinant proteins. Screening of sera from healthy individuals, CRC from Indian origin, and CRC from middle-east Asia origin were performed. Bio-statistical analysis was performed to identify significant autoantibodies altered. Pathway analysis was performed to explore the underlying mechanism of the disease.The comprehensive proteomic analysis revealed dysregulation of 15 panels of proteins including CORO7, KCNAB1, WRAP53, NDUFS6, KRT30, and COLGALT2. Further biological pathway analysis for the top dysregulated autoantigenic proteins revealed perturbation in important biological pathways such as ECM degradation and cytoskeletal remodeling etc. CONCLUSIONS AND CLINICAL RELEVANCE: The generation of an autoimmune response against cancer-linked pathways could be linked to the screening of the disease. The process of immune surveillance can be detected at an early stage of cancer. Moreover, AAbs can be easily extracted from blood serum through the least invasive test for disease screening.

A chitosan-derived metal-free N-doped carbon catalyst was synthesized and investigated for selective reductive formylation of quinoline to N-formyl-tetrahydroquinoline and nitroarenes to N-formyl anilides via aqueous formic acid (FA)-mediated catalytic transformation. FA dissociated on the catalyst surface and acted as a hydrogenating and formylating source for selective N-formylation of N-heteroarenes. The carbonized catalyst prepared at 700 °C offered the best activity. A 92 % yield of N-formyl-tetrahydroquinoline after 14 h and99 % yield for N-formyl anilide after 12 h at 160 °C were obtained. The excellent catalytic activity was correlated with the type of "N" species and the basicity of the catalyst. Density functional theory calculations revealed that a water-assisted FA decomposition pathway (deprotonation and dehydroxylation) generated the surface adsorbed -H and -HCOO species, required for the formation of N-formylated products. In addition, the selective formation of N-formyl-tetrahydroquinoline and N-formyl anilides was explained by a comprehensive reaction energetics analysis.

The coronavirus disease 2019 (COVID-19) pandemic continues to ravage the world, with many hospitals overwhelmed by the large number of patients presenting during major outbreaks. A rapid triage for COVID-19 patient requiring hospitalization and intensive care is urgently needed. Age and comorbidities have been associated with a higher risk of severe COVID-19 but are not sufficient to triage patients. Here, we investigated the potential of attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy as a rapid blood test for classification of COVID-19 disease severity using a cohort of 160 COVID-19 patients. A simple plasma processing and ATR-FTIR data acquisition procedure was established using 75% ethanol for viral inactivation. Next, partial least-squares-discriminant analysis (PLS-DA) models were developed and tested using data from 130 and 30 patients, respectively. Addition of the ATR-FTIR spectra to the clinical parameters (age, sex, diabetes mellitus, and hypertension) increased the area under the ROC curve (C-statistics) for both the training and test data sets, from 69.3% (95% CI 59.8–78.9%) to 85.7% (78.6–92.8%) and 77.8% (61.3–94.4%) to 85.1% (71.3–98.8%), respectively. The independent test set achieved 69.2% specificity (42.4–87.3%) and 94.1% sensitivity (73.0–99.0%). Diabetes mellitus was the strongest predictor in the model, followed by FTIR regions 1020–1090 and 1588–1592 cm–1. In summary, this study demonstrates the potential of ATR-FTIR spectroscopy as a rapid, low-cost COVID-19 severity triage tool to facilitate COVID-19 patient management during an outbreak.

To date, no studies are available in which pituitary adenomas (PAs) have been studied using techniques like confocal Raman spectroscopy, attenuated total reflection-Fourier transform infrared (FT-IR), and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the same serum samples. To understand the metabolomics fingerprint, Raman spectra of 16 acromegaly, 19 Cushing's, and 33 nonfunctional PA (NFPA) and ATR-FTIR spectral acquisition of 16 acromegaly, 18 Cushing's, and 22 NFPA patient's serum samples were acquired. Next, Principal component-based linear discriminant analysis (PC-LDA) models were developed, Raman spectral analysis classified acromegaly with an accuracy of 79.17%, sensitivity of 75%, and specificity of 81.25%, Cushing's with an accuracy of 66.67%, sensitivity of 100%, and specificity of 52.63%, and NFPA with an accuracy of 73.17%, sensitivity of 75%, and specificity of 72.73%. ATR-FTIR spectral analysis classified acromegaly with an accuracy of 95.83%, sensitivity of 100%, and specificity of 93.75%, Cushing's with an accuracy of 65.38%, sensitivity of 87.5%, and specificity of 55.56%, and NFPA with an accuracy of 70%, sensitivity of 87.5%, and specificity of 43.75%. In either of the cases, healthy individual cohorts were clearly segregated from the disease cohort, which identified differential regulated regions of nucleic acids, lipids, amides, phosphates, and polysaccharide/C-C residue α helix regions. Furthermore, LC-MS/MS-based analysis of sera samples resulted in the identification of various sphingosine, lipids, acylcarnitines, amino acids, ethanolamine, choline, and their derivatives that differentially regulated in each tumor cohort. We believe cues obtained from the study may be used to generate the metabolite-based test to diagnose PAs from serum in addition to conventional techniques and also to understand disease biology for better disease management, point of care, and improving quality of life in PA patients.

The rising level of anthropogenic carbon dioxide in the atmosphere drives researchers to look for promising techniques to convert CO2 into useful end products, such as fuel. The artificial conversion of CO2 using photocatalysts has gained significant attention in recent years. In particular, the photoreduction of CO2 into hydrocarbon fuels appears to be a dual approach to tackle energy and environmental issues. This chapter first discusses the photocatalytic applications of 2D hybrid materials followed by the principles of photocatalytic CO2 reduction. The preparations of several 2D materials such as graphene-based, graphitic carbon nitride-based (g-C3N4), transition metal-oxides (TMO), and transition metal-chalcogenide (TMC) photocatalysts are described. Graphene and graphitic carbon nitride (g-C3N4) remained exceptional 2D materials because of their electronic and physicochemical properties. Further, the photocatalytic reduction of CO2 into fuel and chemicals using a photoelectrochemical approach and using several nanosized 2D hybrid materials (i.e., 0D/2D, 1D/2D, and 2D/2D nanomaterials) is discussed. Moreover, the insights of CO2 to fuel conversion processes are elaborated using the density functional theory (DFT) tool which opens new avenues for designing more efficient photocatalysts for CO2 conversion into hydrocarbon fuels.

In recent times, selective hydrogenation of biomass-derived 5-hydroxymethylfurfural (5-HMF) to produce the novel difuranic polyol scaffold 2,5-dihydroxymethylfuran (DHMF) has attracted the interest...

Conventional fire-retardant composite coatings are typically made of organic-based materials that reduce flame spread rates. However, the associated chemical reactions and starting precursors produce toxic and hazardous gases, affecting the environment and contributing to climate change. Wood is one of the most common materials used in construction and households, and thin-film fire-retardant coatings are needed to protect it from fire. Here, we derive high-performance nanocomposite paint-based coatings from naturally occurring and highly insulating layered vermiculite. The coatings are made using different weight percentages of shear-exfoliated vermiculite nanosheets in an epoxy matrix and are brush-coated onto teak wood. A series of tests using coated wooden rods and standard fire retardancy tests confirm a reduction in flame spread and combustion velocity with minimal toxic smoke release. Samples coated with the vermiculite/epoxy nanocomposite paint resist fire propagation, and post-combustion analysis indicates their resistance to thermal degradation. Our results offer a novel and eco-efficient solution to minimize the flame propagation rate, enhancing char development, and expand the scope of applications of ultra-thin vermiculite in nanocomposite coatings as a fire retardant, exploiting its low thermal conductivity in thermal insulation systems.

Catalytic hydrodeoxygenation of fast pyrolysis bio-oils is a potential approach for producing green fuels. This process requires active and inexpensive catalysts with bifunctionality favoring C–O b...

To date, very few Mass spectrometry (MS) based proteomics studies are available on the anterior and posterior lobes of the pituitary. In the past, MS-based investigations have focused exclusively on the whole pituitary gland or anterior pituitary lobe. In this study, for the first time, we performed a deep MS-based analysis of 5 Anterior and 5 Posterior matched lobes to build the first lobe-specific Pituitary Proteome Map which documented 4090 proteins with isoforms, mostly mapped into Chromosomes 1, 2, and 11. About 1446 differentially expressed significant proteins (DEPs) were identified, which were studied for lobe specificity, biological pathway enrichment, protein-protein interaction (PPI), regions specific comparison of human brain and other neuroendocrine glands from Human Protein Atlas (HPA) to identify pituitary enriched proteins. Hormones specific to each lobe were also identified and validated with PRM-based target verification. The study identified and validated hormones GH and TSHβ exclusively to the anterior lobe, while OXT and AVP to the posterior lobe. The study also identified protein POU1F1, POMC, PCOLCE2, and NPTX2 as pituitary enriched proteins and was validated for their lobe specificity using PRM. In addition, three uPE1 proteins, namely THEM6, FSD1L and METTL26 were identified using the NeXtProt database and depicted tumour markers S100s proteins having high expression in the posterior lobe. In summary, the study documents the first matched anterior and posterior pituitary proteome map acting as a reference control for a better understanding of functional and nonfunctional pituitary adenomas and extrapolating the aim of the Human Proteome Project (HPP) toward the investigation of the proteome of life.

Internet of Things (IoT) is a trending technological field that converts any physical object into a communicable smarter one by converging the physical world with the digital world. This innovative technology connects the device to the internet and provides a platform to collect real-time data, cloud storage, and analyze the collected data to trigger smart actions from a remote location via remote notifications, etc. Because of its wide-ranging applications, this technology can be integrated into almost all the industries. Another trending field with tremendous opportunities is Nanotechnology, which provides many benefits in several areas of life, and helps to improve many technological and industrial sectors. So, integration of IoT and Nanotechnology can bring about the very important field of Internet of Nanothings (IoNT), which can re-shape the communication industry. For that, data (collected from trillions of nanosensors, connected to billions of devices) would be the ‘ultimate truth’, which could be generated from highly efficient nanosensors, fabricated from various novel nanomaterials, one of which is graphene, the so-called ‘wonder material’ of the 21st century. Therefore, graphene-assisted IoT/IoNT platforms may revolutionize the communication technologies around the globe. In this article, a status review of the smart applications of graphene in the IoT sector is presented. Firstly, various green synthesis of graphene for sustainable development is elucidated, followed by its applications in various nanosensors, detectors, actuators, memory, and nano-communication devices. Also, the future market prospects are discussed to converge various emerging concepts like machine learning, fog/edge computing, artificial intelligence, big data, and blockchain, with the graphene-assisted IoT field to bring about the concept of ‘all-round connectivity in every sphere possible’.

Heterocycles represent one of the largest groups of organic moieties with significant medicinal, chemical, and industrial applications. Herein, we report the discovery and development of visible-light-induced, synergistic excited-state copper catalysis using a combination of Cu(IPr)I as a catalyst and rac-BINAP as a ligand, which produces more than 10 distinct classes of heterocycles. The reaction tolerates a broad array of functional groups and complex molecular scaffolds, including derivatives of peptides, natural products, and marketed drugs. Preliminary mechanistic investigation suggests in situ generations of [Cu(BINAP)(2)](+) and [Cu(IPr)(2)](+) catalysts that work cooperatively under visible-light irradiation to facilitate catalytic carbo-aroylation of unactivated alkenes, affording a wide range of useful heterocycles.

Alumina supported cobalt (Co) and cobalt-iron (CoFe) catalysts are active for CO2 hydrogenation. Different amounts of CO and CH4 are produced depending on the Co and Fe content. The composition of alumina supported CoFe that maximizes the methane yield for the CO2 methanation reaction was determined using statistically defined experiments and response surface methodology. The catalyst that maximized the methane yield contained 21.47 wt% Co and 2.53 wt% Fe on this alumina support. X-ray diffraction and temperature programme reduction studies showed that Fe enhances the reducibility of cobalt oxides to metallic cobalt. Furthermore, transmission electron microscopy with elemental analysis showed uniform distribution of Co and Fe as an evidence of CoFe bimetallic alloy formation. DFT calculations were used to study the adsorption of CO2 and its dissociation into CO and O on Co and CoFe catalysts. A comparison of reaction energy profiles reveals that CO2 dissociation becomes difficult on the CoFe catalyst containing the optimized composition. The experimentally observed increase in methane formation over CoFe catalyst is probably due to this inhibition of CO formation via CO2 dissociation.

To identify the specific diagnostic biomarkers related to pituitary adenomas (PAs), we performed serological antibody profiles for three types of PAs, namely Acromegaly, Cushing's and Nonfunctional Pituitary Adenomas (NFPAs), using the human proteome (HuProt) microarray. This is the first study describing the serum autoantibody profile of PAs.We performed serological autoantibody profiling of four healthy controls, four Acromegaly, three Cushing's and three NFPAs patient samples to obtain their autoantibody profiles, which were used for studying expression, interaction and altered biological pathways. Further, significant autoantibodies of PAs were compared with data available for glioma, meningioma and AAgAtlas for their specificity.Autoantibody profile of PAs led to the identification of differentially expressed significant proteins such as AKNAD1 (AT-Hook Transcription Factor [AKNA] Domain Containing 1), NINJ1 (Nerve injury-induced protein 1), L3HYPDH (Trans-3-hydroxy-L-proline dehydratase), RHOG (Rho-related GTP-binding protein) and PTP4A1 (Protein Tyrosine Phosphatase Type IVA 1) in Acromegaly. Protein ABR (Active breakpoint cluster region-related protein), ST6GALNAC6 (ST6 N-acetylgalactosaminide alpha-2, 6-sialyltransferase 6), NOL3 (Nucleolar protein 3), ANXA8 (Annexin A8) and POLR2H (RNA polymerase II, I and III subunit H) showed an antigenic response in Cushing's patient's serum samples. Protein dipeptidyl peptidase 3 (DPP3) and reticulon-4 (RTN4) exhibited a very high antigenic response in NFPA patients. These proteins hold promise as potential autoantibody biomarkers in PAs.

Stable catalyst development for CO

Protein microarrays are a diverse and high-throughput platform for screening biomolecular interactions, autoantigens, and protein expression profiles across tissues, etc. Autoantibodies produced against aberrant protein expression are often observed in malignancies which makes protein microarrays a powerful platform to elucidate biomarkers of translational interest. Early diagnosis of malignancies is an enduring clinical problem that has a direct impact on disease prognosis. Here, we provide an overview of a method employed to screen autoantibodies using patient sera in brain tumors. In case of brain malignancies, early diagnosis is particularly challenging and often requires highly invasive brain biopsies as a confirmatory test. This chapter summarizes the various considerations for applying a serum-based autoantibody biomarker discovery pipeline that could provide a minimally invasive initial diagnostic screen, potentiating classical diagnostic approaches.

Protein microarrays are a diverse and high-throughput platform for screening biomolecular interactions, autoantigens, and protein expression profiles across tissues, etc. Autoantibodies produced against aberrant protein expression are often observed in malignancies which makes protein microarrays a powerful platform to elucidate biomarkers of translational interest. Early diagnosis of malignancies is an enduring clinical problem that has a direct impact on disease prognosis. Here, we provide an overview of a method employed to screen autoantibodies using patient sera in brain tumors. In case of brain malignancies, early diagnosis is particularly challenging and often requires highly invasive brain biopsies as a confirmatory test. This chapter summarizes the various considerations for applying a serum-based autoantibody biomarker discovery pipeline that could provide a minimally invasive initial diagnostic screen, potentiating classical diagnostic approaches.

In this book chapter, we will discuss about plethora of two-dimensional (2D) layered materials, their structure, and the unique combination of physical properties. Graphene is one of the first and ultrathin 2D material where in-plane atoms are covalent bonded and through-plane atoms are through van der Waals interaction provide the way for controlling anisotropic physical properties. The physical properties of 2D materials are tuned by controlling the number of layers. Graphene is semimetallic without any bandgap resulting in limited usability in electronics and opto-electronics applications resulted in the discovery of transition metal dichalcogenides (TMDs) especially MoS2 with different polymorphs and ability in tuning the bandgap finds applications in catalysis and electronics. However, TMD-based nanosheets exhibit direct band gap only in the single layered form and exhibit indirect bandgap in multilayers. The re-discovery of black phosphorus emerged as nascent electronic 2D material with exceedingly high-hall mobility and widely tunable direct bandgap irrespective of layers in the nanosheets. In addition to the above, the structures of boron nitride, MXenes, layered double hydroxides, and phyllosilicates are discussed.

Prognosis and management of COVID-19 severity is a challenge even after months of the pandemic. Host plasma proteome alterations carry insights into the physiological alterations in response to the infection. Here we employed a mass spectrometry-based label-free quantitative proteomics approach to study alteration in plasma proteome in a cohort of 73 patients (20 COVID negative, 18 non-severe, and 33 severe) to understand the disease dynamics for addressing this challenge. Of the 1200 proteins detected in the patient plasma, 38 proteins were differentially expressed between non-severe and severe groups. The host proteins such as Angiotensinogen, apolipoprotein B, SERPINA3, SERPING1, and Fibrinogen gamma chain identified in LFQ analysis were further validated using targeted mass spectrometry assay. Utilizing our proteomics dataset, we identified multiple drugs that could inhibit the upregulated proteins involved in disease pathogenesis of these 2 FDA-approved drugs Selinexor and Ponatinib, which showed promise of being re-purposed for potential therapeutics of COVID-19. Plasma proteome identified significant dysregulation in the pathways related to peptidase activity, regulated exocytosis, blood coagulation, complement activation, leukocyte activation involved in immune response, and response to glucocorticoid biological processes during severe SARS-CoV-2 infection. Further, the results suggest that COVID-19 severity can be prognosticated using specific biomarkers of severity, and few of these proteins are excellent targets for re-purposed drugs.

Visible-light photoredox catalysis enables easy access to acyl radicals under mild reaction conditions. Reactive acyl radicals, generated from various acyl precursors such as aldehydes, α-keto acids, carboxylic acids, anhydrides, acyl thioesters, acyl chlorides, or acyl silanes, can undergo a diverse range of synthetically useful transformations, which were previously difficult or inaccessible. This review summarizes the recent progress on visible-light-driven acyl radical generation using transition-metal photoredox catalysts, metallaphotocatalysts, hypervalent iodine catalysts or organic photocatalysts.1 Introduction2 The Scope of This Review3 Aldehydes as a Source of Acyl Radicals4 α-Keto Acids as a Source of Acyl Radicals5 Carboxylic Acids as a Source of Acyl Radicals6 Anhydrides as a Source of Acyl Radicals7 Acyl Thioesters as a Source of Acyl Radicals8 Acyl Chlorides as a Source of Acyl Radicals9 Acyl Silanes as a Source of Acyl Radicals10 Conclusions and Future Outlook

Fast pyrolysis is a promising route for the production of fuels and high value chemicals from non-fossil fuel resources like biomass. However, the design of active and inexpensive catalysts that can selectively convert furfural, an important component in pyrolysis derived bio-oil, to target chemicals remains a challenge. In this context, Ni-based catalysts are potential candidates for the vapor phase activation of furfural in the presence of H2. In this paper, mechanisms and energetics (kinetics and thermodynamics) of the catalytic conversion of furfural to furans, furfuryl alcohol, and C4 products in the presence of H2 on Ni(111) are established, and the experimentally observed change in the selectivity with temperature is explained, using first-principles density functional theory. Hydrogen adsorbs stronger than furfural on the Ni surface. At low operating temperatures, hydrogen adsorption is spontaneous, leading to high hydrogen surface coverages that favor furfural hydrogenation and decarbonylation ov...

Cement industries are the second-largest anthropogenic carbon dioxide (CO2) emitter, have gained substantial research attention to capture CO2 and minimize environmental issues. Also, the recovered carbon dioxide (CO2) can be reutilized for several applications. The adsorptive capture of CO2 appears promising as compared to absorption, membrane separations, and cryogenic distillation because it allows easy CO2 recovery. This work demonstrates the adsorptive capture of carbon dioxide on amine-functionalized styrene-divinylbenzene copolymer. Both batch and continuous adsorption data of CO2 are presented at different temperatures. The equilibrium uptake of CO2 over the polymeric adsorbent showed 2.4 mole/kg capacity at 25⁰C and near ambient pressure, which decreased by 16% with a ten-degree rise in the operating temperature. The equilibrium adsorption data are modeled with Langmuir, Nitta, Toth, Dubinin-Radushkevich, and SIPS isotherm equations to characterize the CO2-polymer adsorption system and estimate the heat of adsorption, entropy, and Gibbs free energy for CO2 adsorption. The Toth isotherm gave the best fit of the experimental data suggesting monolayer adsorption of CO2 on energetically different sites of the adsorbent. The diffusivity of CO2 within the adsorbent’s interstitial space is determined as 2 – 9 ×10-11 m2/sec, indicating intraparticle mass transfer limitations for large-scale operations. The continuous adsorption/desorption studies of CO2 in mixtures with nitrogen were characterized via breakthrough curves. The desorption studies showed 92% – 94% recovery of CO2 in batch and continuous experiments at 56⁰C. A theoretical model for continuous adsorption of CO2 is also developed and validated with the experimental data. The current work could be promising for CO2 capture in the cement industry.

CO activation to generate CH groups is a key reaction step in Fischer–Tropsch synthesis. While several mechanistic proposals can be found in the literature, they often do not account for the high coverage and the cobalt surface structure under reaction conditions. Thermodynamic arguments and in situ scanning tunneling microscopy (STM) images demonstrate that the cobalt surface undergoes a reconstruction to form triangular nanoislands terminated by carbon and CO-covered step sites. Using density functional theory, we evaluate several CO activation pathways at the edges of these nanoislands and propose a cycle involving the creation of a free site through C hydrogenation and CH migration to terraces, followed by CO dissociation at the step sites of the nanoislands. Hydrogen is hence required to create a vacancy site where CO can dissociate, providing an alternative explanation for the kinetic role of hydrogen. An Arrhenius activation energy of 135 kJ/mol and a CO TOF on the order of 10–2 s–1 at 500 K are co...

For the sustainable production of fuel, biomass pyrolysis processes have appeared as a promising alternative for the efficient utilization of biomass. The liquid product obtained from biomass pyrolysis, i.e., bio-oil has a very complex composition including large proportion of organic oxygenated hydrocarbon compounds and appreciable amount of water. The high oxygen content of the bio-oil creates many major drawbacks that hinder its vast application. The quality of bio-oil is not applicable for direct transportation purposes, and its upgrading is mandatory before it can be used practically in power engines. The abovementioned drawbacks can be overcome by the catalytic hydrodeoxygenation of bio-oil, in which the functional groups containing oxygen are removed and replaced by hydrogen atoms. For this purpose of selectively activating and breaking the C–O bonds while trying to maintain the C–C bonds intact, processing knowledge base of petroleum industry may not be utilized for hydrodeoxygenation of bio-oil. Therefore, novel catalysts, solvents, and processes need to be developed. This chapter reviews the state-of-the-art results obtained from the research and development of these technologies. The pros and cons, potential of future applications, challenges related to these technologies, and opportunities to maximize economic and environmental benefits while minimizing pollution are highlighted. Besides, the application of molecular modeling in the integration with experiment is highlighted in this chapter as a new paradigm for mechanistic studies, which could open new avenues to design and develop catalysts for a plethora of bio-oil upgrading processes that require high activity and selectivity. Finally, the breakthrough applications of novel sonochemical technique in biomass treatment and conversion are introduced in this chapter.

The hydrogenation of CO2 to methanol over Cu-nanoparticles supported on TiO2 nanocrystals was studied at 30 bar pressure and 200−300 °C. 5 wt% Cu-TiO2 catalyst was synthesized by a modified hydrothermal method (Cu-TiO2HT) and by incipient wetness impregnation method (Cu-TiO2IMP). TEM analysis of the Cu-TiO2HT catalyst revealed the formation of Cu-nanoparticles (3-5 nm), while larger Cu particle sizes were observed on the Cu-TiO2IMP catalyst. The Cu-TiO2HT catalyst showed superior catalytic activity (CO2 conversion ∼ 9.4 %) and methanol selectivity (∼ 96 %) at 200 °C and 30 bar pressure. Low CO2 conversions (∼6%) and high CO selectivity (∼40 %) was obtained on the Cu-TiO2IMP catalyst. Density functional theory (DFT) calculations indicated the CO2 activation to methanol to proceed via a reverse water gas shift pathway with a significantly lower (93 kJ/mol) CO2 activation barrier on the Cu-nanoparticles, relative to the larger Cu particles (127 kJ/mol). In addition, the higher selectivity towards methanol over the Cu-TiO2HT catalyst was attributed to the higher CO and HCO stability on the Cu nanoparticles. Time of stream (TOS) study of the Cu-TiO2 catalysts showed no significant deactivation even after 150 h with molar feed ratio 1:3:1 (CO2:H2: N2) at 200 °C.

Copper (Cu) is a commercial catalyst for the synthesis of methanol from syngas, low-temperature water gas shift reaction, oleo-chemical processing, and for the fabrication of graphene by chemical vapor deposition. However, high barriers for C–H bond activation and the ease of formation of carbon/graphene on its surface limits its application in the utilization and conversion of methane to bulk chemicals. In the present paper, using first-principles calculations, we predict that Cu catalyst doped with a monolayer of sub-surface boron (B–Cu) can efficiently activate the C–H bond of methane and can selectively facilitate the C–C coupling reaction. Boron binds strongest at the sub-surface octahedral site of Cu and the thermodynamic driving force for the diffusion of B from an on-surface to the sub-surface position in Cu is stronger than that for the experimentally synthesizable B–Ni (sub-surface boron in nickel) catalyst, providing a proof of concept for the experimental synthesis of this novel catalyst. Addi...

An iron(III)-catalyzed C-3 functionalization of flavones has been achieved using tert-butyl peroxybenzoate (TBPB)/potassium persulphate (K2S2O8) oxidant combinations with a suitable solvent. In the presence of iron(III)/tert-butyl peroxybenzoate/potassium persulphate, the reaction of flavones in cycloalkanes afforded exclusive C-3 cycloalkylation via Csp2 –Csp3 coupling, whereas the solvent N,N-dialkylformamide provided C-3 amidation via Csp2 –Csp2 coupling. Under identical reaction conditions just by switching the solvent to chlorobenzene, C-3 methylated flavones were obtained where tert-butyl peroxybenzoate (TBPB) served as the source of the methyl group.

An unprecedented palladium(II)-catalyzed biomimetic aliphatic acyl (-COR) group transfer was observed from acyl-α-peroxycoumarins to the ortho CH sites of directing arenes. Here, the CH activation is associated with a concomitant acyl group transfer via a Pd(II)-catalyzed, redox-neutral process. While methods for ortho aroylation (-COAr) are well documented ortho acylation (-COR) processes are scarce, hence the present redox-neutral method is most ideal for o-acylation of directing substrates.

Late-stage synthesis of α,β-unsaturated aryl ketones remains an unmet challenge in organic synthesis. Herein, we report a photocatalytic non-chain radical aroyl-chlorination of alkenes via 1,3-chlorine atom shift to form β-chloroketones as masked enones that liberate the desired enones upon workup. This strategy suppresses side reactions of enone products such as double aroylation, E/Z isomerization, [2+2]-dimerization, and cross-[2+2]-cycloaddition under photoredox-catalysed conditions. The reaction tolerates a wide array of functional groups and complex molecules including derivatives of peptides, sugars, natural products, nucleosides, and marketed drugs, and offers a potential application in modern drug discovery programs. Notably, addition of 2,6-di-tert-butyl-4-methyl-pyridine enhances the quantum yield and efficiency of the cross-coupling reaction. Experimental and computational studies suggest a mechanism involving PCET, formation and reaction of α-chloro-α-hydroxy benzyl radical, and 1,3-chlorine atom shift. These discoveries and mechanistic insights are useful in the development of new photocatalytic reactions.

In this work, with Ni (110) as a model catalyst surface and CO2 as an adsorbate, a performance study of Density Functional Theory methods (functionals) is performed. CO being a possible intermediate in CO2 conversion reactions, binding energies of both, CO2 and CO, are calculated on the Ni surface and are compared with experimental data. OptPBE-vdW functional correctly predicts CO2 binding energy on Ni (−62 kJ/mol), whereas CO binding energy is correctly predicted by the rPBE-vdW functional (−138 kJ/mol). The difference in computed adsorption energies by different functionals is attributed to the calculation of gas phase CO2. Three alternate reaction systems based on a different number of C=O double bonds present in the gas phase molecule are considered to replace CO2. The error in computed adsorption energy is directly proportional to the number of C=O double bonds present in the gas phase molecule. Additionally, both functionals predict similar carbon–oxygen activation barrier (40 kJ/mol) and equivalent C1s shifts for probe species (−2.6 eV for CCH3 and +1.5 eV CO3−), with respect to adsorbed CO2. Thus, by including a correction factor of 28 kJ/mol for the computed CO2 gas phase energy, we suggest using rPBE-vdW functional to investigate CO2 conversion reactions on different metals.

Syzygium cumini (L.) Skeels (Myrtaceae), commonly known as jambolan or Java plum, is a fast-growing, popular indigenous minor fruit of India. Its leaves, fruits, and seeds have immense medicinal value for treatments of diabetes, chronic diarrhea, enlargement of spleen, ringworm infection, and so on. During May 2018, severe outbreaks of leaf spots occurred on S. cumini plantations in the Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India. Disease incidence ranged from 50 to 100% in some areas of the cultivated orchards. Leaf spot began as a black dot with a distinct yellow halo. These dots enlarged to a diameter of 3 to 5 mm and progressed to form deep brown, circular, elliptical or irregular lesions with a dark black halo around the margin. In a humid environment, black, sessile, and discoid conidiomata developed on the spots and exuded a pink spore mass that turned brown with age. Infected leaves were surface sterilized, plated onto potato dextrose agar (PDA), and incubated under 12-h/12-h cycles of light and darkness for 7 days at 22 to 24°C. The fungal colonies on PDA grew fast, covering the entire plate with a velvety white mycelium with numerous black acervuli. The colony reverse side showed light orange tonalities. Conidia were fusiform (average 26 × 8 µm) (n = 50) and five-celled. Apical and basal cells were hyaline, and the three median cells were dark brown. Conidia showed one short basal and two to four long apical appendages. The identification was confirmed by amplifying and sequencing the rDNA ITS1-5.8S-ITS2 region (GenBank accession no. MN367329) and the D1/D2 region in the 5′ end of the 28S rDNA gene (GenBank accession no. MN371275). BLAST analysis showed in both cases 100% identity with existing sequences of Neopestalotiopsis clavispora (GenBank accession nos. MH423984 and KC154000). The morphological (Maharachchikumbura et al. 2014) and molecular data corresponded to those of N. clavispora. Koch’s postulates were fulfilled for the fungus by spray inoculating two healthy young plants with 2 × 10⁶ conidia per milliliter of sterile distilled water. As a control, two similar plants were sprayed with sterile water. Plants were placed inside plastic bags to maintain humidity and incubated in a growth chamber at 25°C under fluorescent light for 14 h and at 20°C in darkness for 10 h. After 3 days, plastic bags were removed, and plants were maintained under the same conditions. More than 15 days after inoculation, the symptoms described above were observed on the leaves of the inoculated plants, whereas these symptoms did not develop on the control leaves. Cultures isolated from the leaf spots were similar to those isolated previously from plants in the orchard. Several species of Pestalotiopsis were recorded as one of the major problems of S. cumini, including postharvest fruit rot (Srivastava and Mehra 2004), foliar blight (Bhanumathi and Rai 2007), and bark infection (Abbas et al. 2013). Although a leaf blight disease caused by Pestalotiopsis sp. in India was reported in 2007 (Bhanumathi and Rai 2007), the pathogens and symptoms of these two diseases on S. cumini are different according to a comparison of the present study with that of Bhanumathi and Rai (2007). First, the disease symptom observed in our study was in matured plants, whereas in Bhanumathi and Rai (2007) it was S. cumini seedlings. Second, the characteristic symptoms observed in our study were typical 3- to 5-mm-sized leaf spots with a clear dark black halo around the margin of lesions, not previously reported (Bhanumathi and Rai 2007). Third, there were differences in the cultural and morphological characteristics of the mature conidia between the two Pestalotiopsis-like species, including color, conidiogenic cells number and size, and appendages observed under a compound microscope. Therefore, to the best of our knowledge, this is the first report of leaf spot disease on S. cumini caused by N. clavispora in India.

In late summer 2016, necrotic lesions on leaves were observed on Cycas circinalis L. plants, in the Agri-Horticultural Society of India, Alipore Road, Kolkata (located at 22˚53'N; 88°33' E), West Bengal. Based on morphology, DNA sequencing and pathogenicity testing the causal pathogen was identified as Boeremia exigua var. exigua, which is the first report on C. circinalis in India.