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In this paper, the mechanism of the hydroxy(tosyloxy)iodobenzene (HTIB)-mediated conversion of chalcones (α,β-unsaturated carbonyl compounds) to ditosyloxy ketones is investigated. Here, at β-carbon of the chalcone, an aryl group with a para -substituent is present. Our study focuses on investigating the effect of different nature of para -substituents on the reaction mechanism. The substituents considered in the study include -OCH 3 , -SCH 3 , -Cl and -NO 2 groups. For these chalcones, different possible pathways at various steps during the reaction are investigated leading to formation of α,β-ditosyloxy ketones and β,β-ditosyloxy ketones. It is found that the mechanism for the formation of α,β-ditosyloxy ketone involves only electrophilic addition of HTIB, and the mechanism is the same for all studied chalcones, irrespective of whether an electron-donating or electron-withdrawing substituent is present on the aryl ring. However, the detailed mechanism for the formation of β,β-ditosyloxy ketones is different and depends on the nature of the substituent. Broadly, the formation of β,β-ditosyloxy ketones involves electrophilic addition followed by 1,2-aryl migration. Our study shows that the presence of an electron-donating group on the migrating aryl ring favours the formation of β,β-ditosyloxy ketones while in case of electron-withdrawing groups, there are nearly equal chances of the formation of α,β-ditosyloxy ketones and β,β-ditosyloxy ketones.

Conjugated polymers of organic carbonyl compounds are promising electrode materials for energy storage devices owing to the renewable development prospects, structural variability, and better insolubility in electrolyte. However, the synthesis methods in solution are cumbersome and complicated in separation and purification, and require the introduction of functional groups and use of expensive catalysts. In this work, a novel conjugated poly(3,4,9,10-perylenetetracarboxylic diimide) (PPI) with superior thermal stability and lower solubility was prepared successfully by a green facile mechanical ball milling strategy. The PPI exhibits enhanced electrochemical dynamics performance, preferable rate capability, higher discharge capacity, and excellent cycling stability of 450 cycles at 0.2 C with higher capacity retention of 85.7% when used as cathode material for sodium-ion battery. Furthermore, the in-situ X-ray diffraction (XRD) and in-situ Raman investigations combined with the Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) were carried out to investigate the sodium storage mechanism. The results indicate that only two sodium ions are bound to two opposite carbonyl groups of PPI monomer to form sodium enolates during normal charging and discharging and to deliver available reversible capacity.

Carbon Monoxide in Organic Synthesis A thoroughly up-to-date overview of carbonylation reactions in the presence of carbon monoxide In Carbon Monoxide in Organic Synthesis: Carbonylation Chemistry, expert researcher and chemist Bartolo Gabriele delivers a robust summary of the most central advances in the field of carbonylation reactions.

Selective hydrogenation of the carbonyl bond in α,β-unsaturated carbonyl compounds is rather challenging owing to the more feasible hydrogenation of ethylenic bond from both thermodynamic and kinetic aspects. Here, we demonstrate a facile emulsion-based molecule-nanoparticle self-assembly strategy for the atomic engineering of Ir species on three-dimensional CeO 2 spheres (Ir 1 @CeO 2 ). When applied to the hydrogenation of α,β-unsaturated aldehydes, Ir 1 @CeO 2 catalyst remarkably exhibited ~ 100% selectivity towards unsaturated alcohols, whereas the formation of Ir nanoparticles on CeO 2 drastically decreased the selectivity for unsaturated alcohols. Spectroscopic studies revealed that strong metal—support interactions triggered the charge transfer from Ir to CeO 2 , leading to the partial reduction of Ce 4+ to Ce 3+ along with the formation new Ir δ+ —O 2− —Ce 3+ (O V ) interfaces. The electrophilic atomic Ir species at the Ir δ+ —O 2− —Ce 3+ (O V ) interfaces would therefore preferentially adsorb and facilitate hydrogenation of polar C=O bond to achieve exceptional selectivity.

A facile strategy to increase the chemoselectivity of domino reactions was proposed and successfully applied in the α-functionalization of ketones. The strategy involved widening the activation energy of the main reaction and side reaction through intermolecular interactions, thereby increasing the chemoselectivity of the domino reaction. In the proposed α-functionalization reaction, TMSCF3 acted as an excellent reagent which increased the nucleophilicity of DMF through the Van der Waals force and reduced the nucleophilicity of H2O through a hydrogen bond. We found that TMSCF3 can increase the activation energy difference between the main reaction and side reaction using DFT calculations, which greatly increased chemoselectivity and avoided the formation of by-products. TMSCF3 was recycled by rectification, and the average recovery rate was 87.2%. DFT calculations, XRD experiments, and control experiments were performed to support this mechanism. We are confident that this strategy has the potential to deliver significant practical advancements while simultaneously fostering broader innovation in the field of domino synthesis.

A selective electrochemical oxidation was developed under mild condition. Various mono-carbonyl and multi-carbonyl compounds can be prepared from different aromatic hydrocarbons with moderate to excellent yield and selectivity by virtue of this electrochemical oxidation. The produced carbonyl compounds can be further transformed into α-ketoamides, homoallylic alcohols and oximes in a one-pot reaction. In particular, a series of α-ketoamides were prepared in a one-pot continuous electrolysis. Mechanistic studies showed that 2,2,2-trifluoroethan-1-ol (TFE) can interact with catalyst species and generate the corresponding hydrogen-bonding complex to enhance the electrochemical oxidation performance.

The review is focused on the modern trends in the synthesis and chemical properties of β-cyano ketones and transformations of α,β-unsaturated carbonyl compounds taking place in the presence of the cyanide anion and its synthetic equivalents. The state-of-the art analysis of this research field and insights for future studies are given.

Carbonyl compounds represented by aldehydes and ketones make an important contribution to the flavor of tobacco. Since most carbonyl compounds are produced by microbes during tobacco fermentation, identifying their producers is important to improve the quality of tobacco. Here, we created an efficient workflow that combines metabolite labeling with fluorescence-activated cell sorting (ML-FACS), 16S rRNA gene sequencing, and microbial culture to identify the microbes that produce aldehydes or ketones in fermented cigar tobacco leaves (FCTL). Microbes were labeled with a specific fluorescent dye (cyanine5 hydrazide) and separated by flow cytometry. Subsequently, the sorted microbes were identified and cultured under laboratory conditions. Four genera, Acinetobacter , Sphingomonas , Solibacillus , and Lysinibacillus , were identified as the main carbonyl compound–producing microbes in FCTL. In addition, these microorganisms could produce flavor-related aldehydes and ketones in a simple synthetic medium, such as benzaldehyde, phenylacetaldehyde, 4-hydroxy-3-ethoxy-benzaldehyde, and 3,5,5-trimethyl-2-cyclohexene-1-one. On the whole, this research has developed a new method to quickly isolate and identify microorganisms that produce aldehydes or ketones from complex microbial communities. ML-FACS would also be used to identify other compound-producing microorganisms in other systems. Key points • An approach was developed to identify target microbes in complex communities. • Microbes that produce aldehyde/ketone flavor compounds in fermented cigar tobacco leaves were identified. • Functional microbes that produce aldehyde/ketone flavor compounds from the native environment were captured in pure cultures.

The selective reduction of α,β-unsaturated carbonyl compounds is one of the core reactions and also a difficult task for organic synthesis. We have been attempting to study the thermodynamic data of these compounds to create a theoretical basis for organic synthesis and computational chemistry. By electrochemical measurement method and titration calorimetry, in acetonitrile at 298 K, the hydride affinity of two types of unsaturated bonds in α,β-unsaturated carbonyl compounds, their single-electron reduction potential, and the single-electron reduction potential of the corresponding radical intermediate are determined. Their hydrogen atom affinity, along with the hydrogen atom affinity and proton affinity of the corresponding radical anion, is also derived separately based on thermodynamic cycles. The above data are used to establish the corresponding “Molecule ID Card” (Molecule identity card) and analyze the reduction mechanism of unsaturated carbonyl compounds. Primarily, the mixture of any carbonyl hydride ions and Ac-tempo+ will stimulate hydride transfer process and create corresponding α,β-unsaturated carbonyl compounds and Ac-tempoH from a thermodynamic point of view.

A new catalytic one-pot synthesis of N-substituted β-amido carbonyl compounds has been developed using bismuth nitrate as highly efficient, commercially available, recyclable, and reusable acid catalyst. The efficiency of the proposed protocol was demonstrated by 17 examples including various functionalized N-substituted β-amido carbonyl compounds. The reaction utilized easily available and cost-effective starting materials and proceeded at room temperature in a short period of time, followed by aqueous workup.