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Challenges in improving catalysts for electrochemical CO2 reduction require a clear understanding of the reaction mechanisms that lead to products of higher value. In this work, we use density func...

Computational studies are utilized to reveal factors that determine the site selectivity in toluene hydroxylation by cytochrome P450 enzymes (CYPs). The DFT-computed inherent barriers suggest that the priority of product formation is in the order of benzyl alcohol > ortho- ≈ para- > meta-cresol. However, the specific size and shape of the cavities at the active sites of different CYPs dramatically affect the binding orientation of toluene, and thus, the site selectivity can be reordered.

International audience; Divergent Pd-catalyzed reaction cascades with various 1,3-diynamides yielding either 2-amino-3-alkynylindoles or 2-amino-4-alkenylquinolines were established. Omitting or adding TBAF (tetrabutylammonium fluoride) to the reaction of N,N-(2-iodophenyl)(4-toluenesulfonyl)-1,3-diynamides with secondary or primary amines in the presence of KOH in THF and catalytic amounts of Pd(PPh3)4 completely changed the outcome of the reaction. In absence of TBAF, 2-amino-3-alkynylindoles were the sole products, while the presence of TBAF switched the product formation to 2-amino-4-alkenylquinolines. Deuterium labeling proceeded selectively at the C3 and C11 positions of the 2-amino-4-alkenylquinoline products and this suggests the unprecedented formation of [4]cumulenimines from 1,3-diynamides as reactive key intermediates.

We present a model for second-order and pseudo-first-order reversible chemical reactions accelerated using peak-mode isotachophoresis (ITP). In such systems, ITP preconcentrates and co-locates the reactants between the leading and trailing electrolyte zones, and this significantly accelerates chemical reactions. Our model quantifies the effects of reaction rate constants and species abundance on product formation rate. We identify two key non-dimensional parameters, which are specific groupings of reaction rate constants, species concentrations, and influx rates. We then use a regular perturbation to study the effects of reverse reaction rate and relative species abundance (and relative rates of species accumulation) on production rate. We also use this perturbation method to derive an analytical expression for the quasi-steady-state production rate achievable by ITP. Our analytical models and numerical solutions are generally applicable to a wide range of systems, which use ITP to enhance reactions. The model is also an interesting case study of the complex coupling of electric field-driven species transport and reaction kinetics.

Two major challenges facing chemical synthesis are product isolation and catalyst recovery. One method to overcome these challenges is to perform the synthesis in a flow system with a catalytic stationary phase. However, the polymeric catalytic materials used in flow systems are often laborious to produce. In this study, we investigate a novel supramolecular gel as a catalytic stationary phase material. The gel is based on a modular, easy to synthesize, oxotriphenylhexanoate (OTHO) gelator comprised of a catalytic unit designed to catalyze the Knoevenagel reaction. The catalytic organogel enhances the rate of product formation and can be reused five times. Use of the OTHO to construct catalytic gels is a flexible technique that can be utilized to improve product isolation and reduce wastage of the catalyst.

The catalyst-directed divergent synthesis, commonly termed as "divergent catalysis", has emerged as a promising technique as it allows chartering of structurally distinct products from common substrates simply by modulating the catalyst system. In this regard, gold complexes emerged as powerful catalysts as they offer unique reactivity profiles as compared to various other transition metal catalysts, primarily due to their salient electronic and geometrical features. Owing to the tunable soft π-acidic nature, gold catalysts not only evolved as superior contenders for catalyzing the reactions of alkynes, alkenes, and allenes but also, more intriguingly, have been found to provide divergent reaction pathways over other π-acid catalysts such as Ag, Pt, Pd, Rh, Cu, In, Sc, Hg, Zn, etc. The recent past has witnessed a renaissance in such examples wherein, by choosing gold catalysts over other transition metal catalysts or by fine-tuning the ligands, counteranions or oxidation states of the gold catalyst itself, a complete reactivity switch was observed. However, reviews documenting such examples are sporadic; as a result, most of the reports of this kind remained scattered in the literature, thereby hampering further development of this burgeoning field. By conceptualizing the idea of "Divergent Gold Catalysis (DGC)", this review aims to consolidate all such reports and provide a unified approach necessary to pave the way for further advancement of this exciting area. Based on the factors governing the divergence in product formation, an explicit classification of DGC has been provided. To gain a fundamental understanding of the divergence in observed reactivities and selectivities, the review is accompanied by mechanistic insights at appropriate places.

The amide base generated in situ from tetramethylammonium fluoride and N(TMS)3 catalyzes the synthesis of 1,3-diene from an allylbenzene and carbonyl compound. The system is applicable to the transformations of a variety of allylbenzenes with functional groups (halogen, methyl, phenyl, methoxy, dimethylamino, ester, and amide moieties). Acyclic and cyclic diaryl ketones, pivalophenone, pivalaldehyde, and isobutyrophenone are used as coupling partners. The role of trans β-methyl stilbenes in product formation is also elucidated.

Quinolines are N-heterocyclic privileged scaffolds that find immense applications in biological domains and materials science. For example, they act as antimalarial, anti-inflammatory, antiparasitic, antiviral, and anticancer agents. The nucleus of quinolines is abundant in natural products. Various classical approaches to synthesize quinolines are present in the literature. The majority of them involve low yield product formation, tedious workup, and large waste production, which ultimately adds to the environmental burden. Thus, the development of simple, mild strategies to forge such a potent nucleus is highly desirable. On the other hand, in the last five years, visible-light-mediated transformations have also caught significant attention as a greener and eco-friendly route by utilizing photons as a clean energy source. In this context, many researchers have experimented with the synthesis of quinolines under visible light irradiation. Thereby, this review is dedicated solely to the synthesis of quinolines enabled by visible light, wherein most of the described methodologies are accessible under the environment of a blue LED. This review covers the literature from the year 2015 to date.

Introduction. The article considers problems of improving the quality (reducing the number of surface defects, increasing the accuracy of layer formation) of the parts production by additive manufacturing. The existing solutions among the methods and systems of fused deposition are analyzed, the options of avoiding the need of supporting structures usage, avoiding the "step effect", as well as improving the mechanical properties of printed products, such as aerodynamics, resistance to perpendicular loads, etc., through the use of nonplanar 3d-printing.The need to provide feedback of the filament feeding mechanism in order to ensure a more consistent material feed to the area of the 3D product formation has been proven.Research results. The functional structural scheme of the feedback device for increase of technological quality of formation of surfaces of products of exact instrument making by a method of 3D printing in the work is offered.A quality comparison of the obtained products and the performance characteristics of the printing process for sample products without and with the use of the developed feedback device is shown, clear improvement in quality (reduction of surface defects) and accuracy of the products using the proposed design of the feedback device is proven.Conclusions. The features for improving the quality of manufactured parts by 3D printing are enhanced by providing feedback for the feeding mechanism of the filament to ensure a more consistent feed of material in the area of the 3D product formation.The quality of the obtained products and operational characteristics of the printing process of exemplary products without and with the use of the developed feedback device are compared and the unambiguous increase of quality (reduction of the number of surface defects by 88%) and accuracy of the received products (up to 96%) is shown.

The β‐hydroxyacid dehydrogenase from Thermocrinus albus (Ta‐βHAD), which catalyzes the NADP+‐dependent oxidation of β‐hydroxyacids, was engineered to accept imines as substrates. The catalytic activity of the proton‐donor variant K189D was further increased by the introduction of two nonpolar flanking residues (N192 L, N193 L). Engineering the putative alternative proton donor (D258S) and the gate‐keeping residue (F250 A) led to a switched substrate specificity as compared to the single and triple variants. The two most active Ta‐βHAD variants were applied to biocatalytic asymmetric reductions of imines at elevated temperatures and enabled enhanced product formation at a reaction temperature of 50 °C., Get more from your enzyme: A β‐hydroxyacid dehydrogenase from Thermocrinus albus was engineered to accept two different imine compounds as substrates. The variants were applied to biocatalytic asymmetric reductions at elevated temperatures leading to an enhanced product formation.

The surface activity of different zinc alloys was evaluated in wet scCO(2). The zinc coating surface chemistry governed the corrosion product formation. On zinc and Zn-Al coatings, the Al2O3 layer prevented growth of corrosion products. A Zn-Al-Mg coating showed high initial reactivity due to active Zn-Mg phases. An electrogalvanized coating was very active due to a high ratio of exposed, less dense planes. In a Zn-Fe coating, several Zn-Fe phases were susceptible to wet scCO(2) at the same time, triggering the sacrificial effect of Zn. Wet scCO(2) is a convenient medium to assess the early-stage corrosion of metal coatings. acceptedVersion

At elevated temperatures, N-cyanosulfoximines react with Meldrum's acid derivatives to give sulfoximines with N-bound 5-carbonyl-1,3-oxazine-2,4-dione groups. A representative product was characterized by single-crystal X-ray structure analysis. The product formation involves an unexpected molecular reorientation requiring several sequential bond-forming and -cleaving processes.

Journal of the American Chemical Society 142(33), 14286-14294 (2020). doi:10.1021/jacs.0c05917, Published by American Chemical Society, Washington, DC

We present a study based on density functional theory calculations to explore the rate limiting steps of product formation for oxidation by Flavin-containing Monooxygenase (FMO) and glucuronidation by the UDP-glucuronosyltransferase (UGT) family of enzymes. FMOs are responsible for the modification phase of metabolism of a wide diversity of drugs, working in conjunction with Cytochrome P450 (CYP) family of enzymes, and UGTs are the most important class of drug conjugation enzymes. Reactivity calculations are important for prediction of metabolism by CYPs and reactivity alone explains around 70-85% of the experimentally observed sites of metabolism within CYP substrates. In the current work we extend this approach to propose model systems which can be used to calculate the activation energies, i.e. reactivity, for the rate-limiting steps for both FMO oxidation and glucuronidation of potential sites of metabolism. These results are validated by comparison with the experimentally observed reaction rates and sites of metabolism, indicating that the presented models are suitable to provide the basis of a reactivity component within generalizable models to predict either FMO or UGT metabolism.

After two decades teetering at the intersection of laboratory tool and therapeutic reality, with two siRNA drugs now clinically approved, this modality has finally come into fruition. Consistent with other emerging modalities, initial proof-of-concept efforts concentrated on coupling pharmacologic efficacy with desirable safety profiles. Consequently, thorough investigations of siRNA absorption, distribution, metabolism, and excretion (ADME) properties are lacking. Advancing ADME knowledge will aid establishment of in vitro-in vivo correlations and pharmacokinetic-pharmacodynamic relationships to optimize candidate selection through discovery and translation. Here, we outline the emerging siRNA design principles and discuss the consequences for siRNA disposition and biotransformation. We propose a conceptual framework for siRNA ADME evaluation, contextualizing the site of biotransformation product formation with PK-PD modulation, and end with a discussion around safety and regulatory considerations and future directions for this modality.

Enzymes are represented across a vast space of protein sequences and structural forms and have activities that far exceed the best chemical catalysts; however, engineering them to have novel or enhanced activity is limited by technologies for sensing product formation. Here, we describe a general and scalable approach for characterizing enzyme activity that uses the metabolism of the host cell as a biosensor by which to infer product formation. Since different products consume different molecules in their synthesis, they perturb host metabolism in unique ways that can be measured by mass spectrometry. This provides a general way by which to sense product formation, to discover unexpected products and map the effects of mutagenesis., The testing of engineered enzymes represents a bottleneck. Here the authors report a screening method combining microfluidics and mass spectrometry, to map the catalysis of a mutated enzyme, characterise the range of products generated and recover the sequences of variants with desired activities.

This research discusses the Analysis of Work Accidents with FMEA and FTA Methods in the Production Section of PT. YYY Lampung Plant. The purpose of this study is to determine the risk factors that cause work accidents, types of work accidents, work accident rates, and the root causes of work accidents in the production department. This research is a quantitative descriptive study with data analysis using FMEA and FTA methods. The data collection method used primary data in the form of work accident data and secondary data in the form of questionnaires to 50 employees. The results showed that the risk factors for work accidents exist in 5 production process activities, namely in the process of selecting raw materials, cutting, weighing, product formation, and finishing. The types of work accidents that often occur are pinched, crushed, sliced, and hit the body, while the highest accident rate with an RPN value of 350.6 is pinched in the finishing process. The results of this RPN value indicate that the number of work accidents is a very high number (> 200). And the root cause of work accidents based on Fault Tree Analysis on work accidents in the form of being squeezed with a RPN value of 350.6 caused by lack of concentration, employees not feeling well, sleepy workers, and limited (narrow) work space. Based on these data, it can be concluded that the level of work accidents should receive special attention.

Enzymes are represented across a vast space of protein sequences and structural forms and have activities that far exceed the best chemical catalysts; however, engineering them to have novel or enhanced activity is limited by technologies for sensing product formation. Here, we describe a general and scalable approach for characterizing enzyme activity that uses the metabolism of the host cell as a biosensor by which to infer product formation. Since different products consume different molecules in their synthesis, they perturb host metabolism in unique ways that can be measured by mass spectrometry. This provides a general way by which to sense product formation, to discover unexpected products and map the effects of mutagenesis.

α-Pinene, C10H16, represents one of the most important biogenic emissions into the atmosphere. The formation of RO2 radicals HO-C10H16Ox, x = 2-6, and their closed-shell products from the OH + α-pinene reaction has been measured for close to atmospheric reaction conditions in the presence of NO with concentrations of (1.7-490) × 109 molecules cm-3. Main closed-shell products are substances with the composition C10H16O2 and C10H16O4, most likely carbonyls, obtained with molar yields in the range 0.42-0.45 and 0.17-0.19, respectively, for NO concentrations >5 × 1010 molecules cm-3. The corresponding total product yields amount to 0.75-0.81, indicating efficient product detection by the mass spectrometric method applied. All stated molar yields represent lower limit values affected with an uncertainty of [Formula: see text]. Kinetic and product analysis consistently revealed the suppression of the formation of highly oxygenated organic molecules (HOMs) by a factor of 2-2.2 for the highest NO concentration used. The findings of this study provide insights into the RO2 radical processes of the OH + α-pinene reaction for atmospheric conditions and give an overview about the first-generation products.

The reactions of 1-benzoyl-2,4-diphenyl-2,3-dihydro-1H-1,5-benzodiazepine with methyl 1-bromocycloalkanecarboxylates and zinc, followed by hydrolysis of the reaction mixtures, resulted in the formation of spiro-δ-lactams bearing a 2-(N-benzoylamino)phenyl substituent at the nitrogen atom. The product structures were confirmed by X-ray structural analysis, and a mechanism was proposed for the product formation.

We present results detailing the oxidative reactivity of condensed propene thin films, with particular attention to epoxide product formation because of its importance in the industrial production ...

Electron beam deposition is a process that involves the use of an electron beam as a source of energy and wire as a raw material for the fabrication of metal products with complex shape in a vacuum...

A little attempt has been made to get in touch with the green chemistry studying the successful occurrence of oxidation of 4-chlorobenzyl alcohol to 4-chlorobenzaldehyde in micellar media by Cr(VI), and its kinetics has been recorded spectrophotometrically following pseudo-first-order reaction conditions at λmax = 440 nm. In this purpose, some common hetero-aromatic bases like 2-picolinic acid, 1,10-phenanthroline and 2,2′-bipyridine have been utilized successfully for many fold rate enhancement of the reaction. Necessary spectroscopic evidences have been produced in support of the product formation.

Molecular anthracene has been used as an arene in the Friedel-Crafts (FC) type arylation reaction of anthracenyl-α-hydroxyphosphonate in the presence of acid. A diverse product formation is observed, in which anthracene unit is found to be linked through its C1 position with α-C of phosphonate. Interestingly, the molecular conformation (X-ray structure) of this phosphonate reveals one of the bond angles of a tetrahedral carbon as 118° which is close to the C of sp2 character. Further, molecular anthracene is also recognized to attack at the C10 position of 9-anthracenylphosphonate through C1 or C2 or C9 atoms and the structures of three isomeric phosphonates are established with the help of 1H and 31P NMR studies. The bis-anthracenyl compounds with a P-CH2 unit have been successfully utilized in Horner-Wadsworth-Emmons (HWE) reactions to afford extensive bis-anthracenyl-linked π-conjugates.

The chemistry of polyoxomolybdates and polyoxotungstates has been systematically developed since their first discovery more than 100 years ago. In contrast, significant progress in the related chemistries of polyoxovanadates, polyoxoniobates and polyoxotantalates was mainly made during the last few years. This highlight summarizes new synthetic approaches for the generation of high-nuclearity group 5 polyoxometalates and discusses the synthetic conditions influencing product formation. The application of new precursors allows rational syntheses of group 5 polyoxometalates. The importance of the knowledge of the species in liquid media is also discussed and results of in situ investigations are presented.

The contribution of intersystem crossing (ISC) in the C(3P) + SiH4 reaction that leads to products formation in the singlet electronic state is investigated using a direct dynamics trajectory surface hopping (TSH) method with Tully's fewest switches algorithm. Interestingly, in contrast to the O(3P) + SiH4 reaction with no ISC effect, for the title reaction we observed ∼7% product formation through ISC despite weak spin–orbit coupling interactions (less than 25 cm−1) between the ground singlet and triplet states. This is presumably because of the topological differences in the potential energy surfaces of the two reactions at the entrance channel. The O(3P) + SiH4 reaction follows either an addition reaction (with shallow attractive potential and a late singlet–triplet crossing) or a direct abstraction pathway with singlet–triplet crossing at near or after the top of the barrier making ISC ineffective. On the other hand, an insertion mechanism is exclusively followed by the C(3P) + SiH4 reaction with no entrance barrier to the reaction in the triplet state. The triplet insertion complex initially formed (3H3SiCH) can go to the singlet state through ISC due to the fact that the triplet–singlet crossing is accessed several times during the course of the reaction. Our computed overall product angular distributions for H and H2 elimination channels are found to be broad and flat or nearly isotropic in nature indicating the formation of stable intermediate complexes, which corroborates the most recent crossed molecular-beam study.

An investigation of CCl3COCl was conducted with the purpose of using the compound as an alternative Cl atom precursor in laboratory settings. CCl3COCl can be used with or without O2 as a source of Cl atoms and photolysis studies in air and N2 diluent displayed COCl2 and CO as being the major photolysis products. Relative rate studies were performed to determine the Cl atom rate coefficients for reaction with CH3Cl and C2H2 and the results were in agreement with literature values. Cl atom rate coefficients for reaction with n-CH2CH(CH2)3CN and n-CH2CH(CH2)4CN were determined as (2.95 ± 0.58) × 10−10 and (3.73 ± 0.60) × 10−10 cm3 molecule−1 s−1, respectively. CCl3COCl requires UV-C irradiation, so not all molecules are feasible for use in e.g. relative rate studies. Furthermore, it is recommended to perform experiments with O2 present, as this minimizes IR feature disturbance from product formation.

Different substituents at the β-diiminato ligand in low-valent [LFe(tol)] (L = β-diiminato) complexes fundamentally change their reactivity towards yellow arsenic. By using dmp (2,6-dimethylphenyl) as flanking groups, the tetranuclear complexes [(LFe)4As8] (L = L1 (1), L2 (2)) are isolated. For dipp (2,6-diisopropylphenyl) substituted ligands, dinuclear complexes [(LFe)2(cyclo-As4)] (L = L3 (3a), L4 (4a)) are obtained. Not only the choice of the ligand impacts the product formation, but also the temperature of the crystallization can shift their ratio in the solid state.

Although formal Cu(iii) species have been extensively proposed as key intermediates in a wide range of copper-catalyzed reactions, the precise reactivity of these species remains unexclusive. Commonly, a formal reductive elimination mechanism is proposed for the product formation step. In this work, through theoretical investigation of the reactivity between a formal Cu(iii)-alkyl species and aniline, we demonstrated that a SN2-like mechanism could also be responsible for coupling product formation.

Commonly observed competitive substrate inhibition in cometabolism of organic contaminants is used as rate- and reducing-power-determining factors to develop a kinetic model of the competitive cometabolism. Analogous to the well-known theory of Leudeking-Piret kinetics where the product formation demands reducing power, cometabolism is modeled as a reducing power demanding process that also competes with microbial growth for the available reducing power from the degradation of energy-yielding primary substrate. The model further incorporates other growth-associated phenomena such as substrate inhibition and multiple growth/nongrowth substrate interactions that may occur during cometabolic transformation processes. The kinetic model is used successfully to predict a variety of degradation patterns of growth/nongrowth substrates, displayed by microbial cultures when exposed to different concentration ratios of growth to nongrowth substrate: a complete degradation of nongrowth substrates that coincides with the simultaneous depletion of a growth substrate and, in some other cases, an incomplete degradation of a nongrowth substrate following the complete depletion of a growth substrate. These distinct patterns of substrate degradation are attributed to intrinsic specificities of enzymes for cometabolism and lack of reducing power available from the growth substrate degradation. The efficacy of cometabolic capabilities of actively growing microbial cultures and pre-cultured resting cells is discussed in terms of reducing power available in such systems.

This work primarily investigated the pyrolysis of post-consumer mixed plastic wastes during slow pyrolysis (non-isothermal) in a batch reactor to assess the effect of different heating rates on the product yield and its composition. The effect of residence time during fast pyrolysis (Isothermal) in Pyro-GC was also investigated. Initially, TG analysis was performed to investigate the degradation temperature range at different heating rates of 5, 10, 20 and 40 °C/min. Two different heating rates of 10 and 20 °C/min were selected for examining the effect on products such as oil and gases (H2, CO, CO2 and C1-C6 hydrocarbons) during slow pyrolysis. The oil obtained at higher heating rate had higher density (0.743 kg/m3) while the amount of residue decreased with the increase in heating rate. Also, the effect of residence time during fast pyrolysis was investigated using Pyro-GC at 500 °C for the product formation. It was observed that an optimum residence time of 10sec was favourable for the higher production of lower hydrocarbons (C1-C3) and less production of heavier hydrocarbons (C6). This work represents the combined analysis of fast and slow pyrolysis and their impact on the product yield. Also, the effect of heating rate on non-isothermal condition and the effect of the residence time of volatiles in isothermal condition was analysed and reported.

Starting from substituted alkynones, α-pyrones and/or 1H-pyridines were generated in a Michael addition–cyclocondensation with ethyl cyanoacetate. The peculiar product formation depends on the reaction conditions as well as on the electronic substitution pattern of the alkynone. While electron-donating groups furnish α-pyrones as main products, electron-withdrawing groups predominantly give the corresponding 1H-pyridines. Both heterocycle classes fluoresce in solution and in the solid state. In particular, dimethylamino-substituted α-pyrones, as donor–acceptor systems, display remarkable photophysical properties, such as strongly red-shifted absorption and emission maxima with daylight fluorescence and fluorescence quantum yields up to 99% in solution and around 11% in the solid state, as well as pronounced emission solvatochromism. Also a donor-substituted α-pyrone shows pronounced aggregation-induced emission enhancement.

Microbial cell factories offer new and sustainable production routes for high-value chemicals. However, identification of high producers within a library of clones remains a challenge. When product formation is coupled to growth, millions of metabolic variants can be effectively interrogated by growth selection, dramatically increasing the throughput of strain evaluation. While growth-coupled selections for cell factories have a long history of success based on metabolite auxotrophies and toxic antimetabolites, such methods are generally restricted to molecules native to their host metabolism. New synthetic biology tools offer the opportunity to rewire cellular metabolism to depend on specific and non-native products for growth.

Microbial electron uptake (EU) is the biological capacity of microbes to accept electrons from electroconductive solid materials. EU has been leveraged for sustainable bioproduction strategies via microbial electrosynthesis (MES). MES often involves the reduction of carbon dioxide to multi-carbon molecules, with electrons derived from electrodes in a bioelectrochemical system. EU can be indirect or direct. Indirect EU-based MES uses electron mediators to transfer electrons to microbes. Although an excellent initial strategy, indirect EU requires higher electrical energy. In contrast, the direct supply of cathodic electrons to microbes (direct EU) is more sustainable and energy efficient. Nonetheless, low product formation due to low electron transfer rates during direct EU remains a major challenge. Compared to indirect EU, direct EU is less well-studied perhaps due to the more recent discovery of this microbial capability. This mini-review focuses on the recent advances and challenges of direct EU in relation to MES.

A simple, practical and scalable approach for the synthesis of 2-aminobenzothiazolomethyl naphthols using one-flask three-component reaction of 2-aminobenzothiazole, substituted aromatic aldehydes and β-naphthol in water is reported. The reaction is catalyzed by l-valine as non-toxic, green, easily available, cheap, sustainable and biodegradable catalyst. The product formation takes shorter reaction time with good to excellent yield. The method is demonstrated on multi gram level. Easy workup procedure, short reaction time and most importantly environmentally benign are the most outstanding advantages of this procedure.

A mechanism for the degradation of n-heptane and the formation of the products of its plasma-chemical transformation by microwave discharge treatment has been proposed. Chemical reactions resulting in reactive species, namely free radicals that form lower hydrocarbons and polyaromatic structures are presented. The product composition of the gas, liquid, and solid phases has been studied using gas chromatography–mass spectrometry analysis of the precipitate obtained by evaporation of the liquid phase after the treatment of n-heptane.

WOS: 000465322800001, PubMed: 31164929, In this study, we developed a new addition reaction of chlorosulfonyl isocyanate (CSI), starting from 2-ethyl-3a, 4,7,7a-tetrahydro-1H- isoindole-1,3(2H)-dione. The addition reaction of CSI with 2-ethyl-3a, 4,7,7a-tetrahydro-1H-isoindole-1,3(2H)-dione resulted in the formation of ylidenesulfamoyl chloride, whose exact configuration was determined by X-ray crystal analysis. We explain the mechanism of product formation supported by theoretical calculations., Department of Chemistry; Ataturk University; Scientific and Technological Research Council of Turkey [TUBITAK-116Z506], The authors are indebted to Department of Chemistry and Ataturk University for financial support. This research was supported by the Scientific and Technological Research Council of Turkey (TUBITAK-116Z506).

This review describes the recent advances in understanding of the mechanism of palladium catalyzed C–C cross-coupling reactions. The discussion is focused on the role of palladium nanoparticles (Pd NPs) in the catalytic process. In most cases, Pd NPs are not the only form of palladium present in the system, but they contribute in product formation together with other species forming “cocktail of catalysts”. The mixture of catalytically active species can be formed from two types of precursors, namely Pd NPs or Pd(II) complexes. To characterize catalytic systems based on pre-made Pd NPs we selected catalysts immobilized of MOF materials. The other part of review is devoted to the catalytic systems in which Pd NPs are formed in situ from molecular complexes. The role of non-phosphorus ligands in stabilization of Pd NPs was presented and discussed.

This report describes the synthesis of a [2.2]paracyclophane-derived annulated 3-amino-imidazole ligand library via a Groebke-Blackburn-Bienayme three-component reaction (GBB-3CR) employing formyl-cyclophanes in combination with diverse aliphatic and aromatic isocyanides and heteroaromatic amidines. The GBB-3CR gives access to differently functionalized skeletally-diverse cyclophanyl imidazole ligands, namely 3-amino-imidazo[1,2- a ]pyridines and imidazo[1,2- a ]pyrazines. Additionally, a one-pot protocol for the GBB-3CR by an in-situ generation of cyclophanyl isocyanide is demonstrated. The product formation was analyzed by detailed spectroscopic techniques, and a cyclophanyl imidazo[1,2- a ]pyridine was confirmed unambiguously by single-crystal X-Ray crystallography. The cyclophanyl imidazole ligands can be readily transformed to showcase their useful utility in preparing N , C -palladacycles via regioselective ortho -palladation.

The cross-coupling of N-tosylhydrazones and aryl halides forms carbon-carbon bonds, producing 1,1-disubstituted alkenes. Though it has proven extremely useful in several fields of chemistry, its mechanism remains experimentally unexplored. Combining benchtop NMR and real-time mass spectrometry afforded the ability to monitor the catalytic intermediates as well as the rate of product formation.