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A combination of reagents using I2 and DMSO has been established for the selective transformation of unactivated alkenes into iodohydrins and β‐iodoethers. The developed approach was served by the dual roles of DMSO as an oxidant as well as a hydroxylating agent under different solvent systems at 85 °C. The developed method holds an operational simplicity and is consistent with wide range of substituted alkenes to deliver iodohydrins and β‐iodoethers in yields up to 86 %. The formation of iodohydrins are selective in MeCN as solvent and the course of the reaction was examined by GC‐MS studies and DFT method. [ABSTRACT FROM AUTHOR]

An ionic liquid, namely imidazolium sulfonic acid chloride (ISAC) has been electrostatically grafted over cerium oxide nanoparticles to produce a nanocomposite, nano‐CeO2‐IL. The as‐prepared composite was characterized by various analytical techniques such as XRD, FT‐IR, SEM, TEM, XPS, BET, UV‐DRS, PL, and TGA to confirm the grafting of ISAC over CeO2 NPs. The photocatalytic process is regarded as the method of choice for the elimination of air pollutants because of its great efficiency and relatively benign working conditions. According to UV‐DRS spectra, its optical gap is 2.07 eV, which is appropriate for the visible light spectrum. The composite was investigated as a visible‐light‐driven photocatalyst for hydroxylation of benzene to phenol and heavy metal Cr (VI) reduction. Moreover, the scavenger experiments confirmed the detection of ⋅OH radicals which played a crucial role in the photocatalytic experiments. Within 60 minutes, 98.5 % of benzene was converted to phenol with 82.7 % selectivity in addition to 93.63 % Cr (VI) reduction within 30 mins. The photocatalytic reduction of Cr(VI) to Cr(III) follows a first‐order model with a rate constant of 0.027 min−1. The remarkably high photocatalytic performance of the catalyst may be ascribed to the synergistic interaction between the nano‐CeO2 catalyst and ionic liquid. [ABSTRACT FROM AUTHOR]

An asymmetric formal synthesis of (+)‐phomactin A has been accomplished. The key steps in the synthetic strategy included establishing the AB ring system in one‐pot via Prins/Conia‐ene cascade cyclization reaction and the C ring formation via γ‐hydroxylation of enone in the late‐stage of the synthesis. The two major fragments are readily prepared from (+)‐pulegone and geraniol via a modified Eschenmoser–Tanabe fragmentation strategy in 6 steps and a Sharpless asymmetric epoxidation/hydrozirconation/ Roskamp reaction sequence in 11 steps respectively. [ABSTRACT FROM AUTHOR]

In the present work, 4‐hydroxy enigmol (1), an analogue of enigmol which is a known orally bioavailable 1‐deoxysphingolipid, effective against multiple cancer cell lines, has been synthesized with an additional hydroxy group for improved anti‐cancer activity. The additional group in compound (1) is likely to show enhanced activity due to improved cell permeability and hydrophilicity. The key steps involved are stereoselective cross metathesis reaction and OsO4/NMO mediated dihydroxylation. Further, analogues of 4‐hydroxy enigmol (1) with varying chain lengths (2, 3) have also been synthesized using the same synthetic strategy for varying hydrophobicity as an additional structural feature. To support the genesis in the design of compound (1–3), the pharmacokinetic studies and docking analysis has been done for calculating the polar surface area, binding affinity and hydrophobicity/hydrophilicity. The preliminary in‐vitro cytotoxicity on cancer cell lines displayed promising activity against the PC‐3 cell lines and HCT‐116 cell lines. [ABSTRACT FROM AUTHOR]

Numerous academics worldwide are interested in utilizing waste as a resource to produce an epoxide. Epoxidation/ring‐opening of oxirane is a common method for producing polyols from vegetable oil. This study examined the effect of the catalyst type and loading on the ring opening of epoxide groups by utilizing performic acid generated in situ. The outcomes demonstrated that the zeolite catalyst at 0.2 g loading produced the highest conversion of oxirane (RCO%). The FTIR data showed that the epoxy ring group's location caused the hydroxyl group's (O−H) to be observed at 3100–3600 cm−1 in the placement of the epoxy ring group (C−O−C) at 1210–1250 cm−1. Finally, optimization and kinetic modeling using artificial neural networks, abbreviated as Neural Network, is a model of the human brain that is abstracted, simulated, and trained to obtain the value of R closest to 1. [ABSTRACT FROM AUTHOR]

A convenient and diverse common synthetic strategy was developed for total synthesis of conduritol‐E, allo‐inositol, talo‐quercitol, and formal synthesis of palitantin from the common polyhydroxylated cyclohexenol intermediate, which was synthesized from readily available D‐ribose. The synthetic avenue includes Barbier allylation, RCM reaction, and oxidative diol cleavage as key steps. [ABSTRACT FROM AUTHOR]

Selective hydroxylation of benzene to phenol over a visible light driven photocatalyst is a sustainable approach for the green synthesis of phenol. Iron vanadate (FeVO4) nanorods with an intrinsic photo‐Fenton catalytic behavior toward H2O2 activation is a promising candidate photocatalyst for the benzene hydroxylation reaction; however, its photocatalytic performance was greatly limited by the serious leaching of metals during the hydroxylation process. Herein, it has been demonstrated that this issue can be well addressed by the conformably coating of FeVO4 nanorods with an atomically‐precise thickness controlled dense Al2O3 layer (FeVO4@Al2O3) through the atomic layer deposition (ALD) technology. The Al2O3 nanolayer can well protect the FeVO4 nanorods from directly contacting with the reaction solution, thus effectively suppressing the leaching of metals during the photocatalytic hydroxylation process. In addition, the Al2O3 coating on FeVO4 also facilitates the kinetic control of heterogeneous benzene hydroxylation reaction over the catalyst surface, such as the benzene adsorption behavior and the photo‐Fenton activation of H2O2. As a result, FeVO4@Al2O3 exhibited an enhanced photocatalytic performance with a good durability in the long‐term production of phenol. [ABSTRACT FROM AUTHOR]

An alternative and highly efficient ʟ‐rhamnosylation highlighting the dual‐catalysis of ruthenium reagent under a stereocontrolled process has been realized. The Ru‐mediated direct glycosylation‐dihydroxylation from ʟ‐rhamnal is amenable to a wide range of acceptors, including sugars, amino acids, natural products, and bioactive scaffolds. The one‐pot protocol tolerating diverse functional groups is attractive due to the valuable synthetic utility in assembling biologically significant α‐ʟ‐rhamnopyranosides in good yields. The mechanistic rationalization for the α‐anomeric selectivity and syn‐diastereoselective dihydroxylation employing Ru‐catalysis has been presented. [ABSTRACT FROM AUTHOR]

Rieske dioxygenases have a history of utility in organic synthesis, owing to their ability to catalyze the asymmetric dihydroxylation of aromatics to produce chiral diene‐diol metabolites. However, their utility as green‐chemical tools has been limited by steric and electronic constraints on their substrate scopes and their activity. Herein we report the rational engineering of a widely used Rieske dioxygenase, toluene dioxygenase (TDO), to improve the activity of this enzyme system for the dihydroxylation of a synthetically valuable substrate class for which the wild‐type enzyme possesses low activity, the ester‐functionalized aromatics. Through active site targeted mutagenesis and application of a recently reported high throughput screening platform, engineered TDO variants with significantly increased activity in the dihydroxylation of these valuable substrates were identified and characterized, revealing key active site residues that modulate the enzyme's activity and selectivity. [ABSTRACT FROM AUTHOR]

Cephalostatins (e. g. cephalostatin 1) are a class of natural products that exert extraordinary antitumor activity with the presence of a significant number of oxygen atoms either in etheric, alcoholic, or epoxydic form. Here, we describe a novel epoxidation method of ▵14,15 bond of the symmetrical bis‐steroidal pyrazine (BSP) (the diketone 2) using only grounded lithium metal in dry THF. This chemo and regioselective method which forms an environmentally begin solved one of the major challenges that overcome the N‐oxide formation in BSP's. The epoxidized products underwent a regioselective reduction with sodium borohydride NaBH4 yielding 15α‐hydroxy derivatives. Interestingly, the triol derivative 5 was found to exert a powerful activity against the three selected cancer cell lines: K562, MCF‐7, and DU‐145 using MTT assay (average GI50<0.1 μM). Noteworthy, the BSP 7 (with vicinal‐diol functionality) was obtained when the epoxidized derivatives 4 was treated with sodium metal in dry THF. [ABSTRACT FROM AUTHOR]

Herein, we report for the first time the aldol reaction of a wide range of α‐ketoamide with α,β‐unsaturated ketone via the activation of potassium hydroxide in aqueous medium. The protocol provides a straightforward and atom‐efficient strategy for the synthesis of a new family of multifunctional α‐hydroxy amides contain α,β‐unsaturated ketone group from easily accessible substituted α‐ketoamide and α,β‐unsaturated ketone. The reaction features mild reaction conditions, green solvent, one of which is quaternary carbon substitution. The method can accommodate various substituents and substitution patterns, afford the products up to 95 % yields. [ABSTRACT FROM AUTHOR]

In this review we discuss the synthetic approaches of chiral and racemic forms of centrolobines from 2002 to date. The presence of unique molecular architecture of tetrahydropyran unit in centrolobine enhances its high biological activity which has created the space to the synthetic community for the last two decades to develop various routes. This review mainly emphasizes on the construction of tetrahydropyran unit and generation of chirality as a key step during the synthesis of centrolobine. Moreover, all the synthetic methods were well demonstrated and presented systematically in the chronological order. Overall this review highlights the contribution from different research groups in the total syntheses of centrolobines. [ABSTRACT FROM AUTHOR]

Unusual products were obtained from cycloadditions reactions of two series of styrylcyclohexene dienes with dienophiles maleic anhydride and N‐phenylmaleimide. Experimental studies revealed that various dienes 3 underwent an initial in‐situ dehydration/double bond rearrangement prior to cycloaddition with maleic anhydride to give products 5 in 78–88 % yields. Alternatively, the cycloadducts of the reactions of 4 with N‐phenylmaleimide were hydoxylated stereoselectively in the same pot to give products 7, along with the usual adducts 6 in 83–89 % yields. Further, the reactions of the diene 4 with the dienophile dimethyl acetylenedicarboxylate were also studied, leading to the formation of the respective adducts 10 in 72–81 % yields. The stereochemistry of the new products was assigned based on their spectroscopic data and, in some cases, with X‐ray crystallography experiments. [ABSTRACT FROM AUTHOR]

The direct hydroxylation of 1,4‐dichlorobenzene (1,4‐DCB) to 2,5‐dichlorophenol (2,5‐DCP) with green oxidant, to replace the conventional multi‐step processes attracted much attention. In this work, activated carbons were prepared by modification firstly using nitric acid, and then the resultant samples were treated with hydrogen peroxide or thermally under nitrogen flow. The prepared samples were applied as heterogeneous catalysts in the one‐step hydroxylation of 1,4‐DCB, and were characterized by XRD, BET, XPS, and Boehm titration. Acetonitrile, isopropanol, glacial acetic acid, and the mixture of them were used as the reaction solvents and EPR was carried to characterize the reaction systems in these solvents. The reaction parameters, such as the feeding speed of H2O2, moles of 1,4‐DCB used, molar ratio of H2O2 to 1,4‐DCB, mass ratio of catalyst to 1,4‐DCB, reaction temperature, and reaction time were optimized. It was found that the direct hydroxylation of 1,4‐DCB could be efficiently catalyzed by activated carbon with acetonitrile as a suitable solvent. Under the optimized conditions, the highest 2,5‐DCP yield of 14.4 % with selectivity of 86.4 % was obtained. The amount of oxygen functional groups on the activated carbon samples resulted in differences in adsorption capacity of 1,4‐DCB and decomposition rate of H2O2, the integrated effect of which might be responsible for the activity. [ABSTRACT FROM AUTHOR]

For the first time, a new, cost‐effective, metal‐free, H2O2 (50 % in water)‐mediated regioselective direct C‐3 hydroxylation of imidazo[1,2‐a]pyridines via C‐H bond functionalization is reported. This metal‐free C(sp2)‐O bond formation protocol is operationally simple and showed broad range of functional group tolerance and substrate affinity. To the best of our knowledge, this is the first report of imidazo[1,2‐a]pyridine‐3‐ols showing promising in vitro antioxidant activity. [ABSTRACT FROM AUTHOR]

An efficient enantioselective approach of Sacubitril 1 (a NEP inhibitor) which is used as a combination drug with Valsartan to treat heart failure, is described. The synthesis features the Evan's asymmetric alkylation, Sharpless asymmetric diydroxylation (AD) and Heck coupling reactions as key steps. [ABSTRACT FROM AUTHOR]

An improvement in the stereoselective total synthesis of unnatural (+)‐oxycodone from phenethyl acetate is described. The total step count was reduced by conducting some chemical transformations in "one‐pot" and a change in the sequence of chemical operations was implemented, in comparison with the previously published first‐generation synthesis. The synthesis of (+)‐oxycodone was completed in a total of 12 operations (17 steps) and an overall yield of 1.6%, in comparison to our previous synthesis (13 operations, 19 steps, 1.5% yield) Experimental and spectral data are provided for all new compounds. [ABSTRACT FROM AUTHOR]

Selective hydroxylation of different phenylboronic acids to phenols was successfully carried out by using Cu nanoparticles‐enzyme hybrid catalysts in water and room temperature. Different Cu‐enzyme hybrids containing Cu(II), Cu(I) and Cu(0) nanoparticles species respectively were tested on the monohydroxylation of phenylboronic acid under these mild conditions being hybrids containing Cu(0)NPs the best catalysts, with total selectivity and formation of phenol as unique product. Also, the addition of hydrogen peroxide or the increase of reaction temperature were tested but did not improved these results. The substrate scope was also demonstrated and the Cu(0)NPs hybrid showed excellent results in the monohydroxylation of different o‐, m‐, p‐substituted phenylboronic acid with final yields >95 %. This catalyst showed excellent recyclability after 5 cycles of use. [ABSTRACT FROM AUTHOR]

An efficient, facile, and clean synthesis of various 3‐hydroxy‐chromones (3‐hydroxy‐4H‐chromene‐4‐ones) via enamino ketone followed by cyclization using m‐chloroperbenzoic acid (MCPBA) has been described. The significant features of this method include simple method, high purity and excellent regio‐selectivity of the products. This is the first report for the two step one pot synthesis of 3‐hydroxyl chromone using MCPBA. [ABSTRACT FROM AUTHOR]

A high‐performance NH2‐MIL‐88B(Fe)‐SA−V for the direct catalytic oxidation of benzene hydroxylation using hydrogen peroxide as the oxidant was designed and prepared. The synthesized material was characterized by scanning electron microscopy, x‐ray powder diffraction, flourier transform infrared spectroscopy and nitrogen adsorption‐desorption. The influence of different parameters on the catalytic performance of NH2‐MIL‐88B(Fe)‐SA−V for benzene hydroxylation was researched. Under optimized condition, the high yield of 22.2% and selectivity of 98.6% were obtained, while the pure NH2‐MIL‐88B(Fe) only gained the yield of 1.2%. Furthermore, the V/Fe3O4 catalyst was obtained by calcination of NH2‐MIL‐88B(Fe)‐SA−V in N2 for photocatalytic recycle, and the yield and selectivity of phenol were 20.2% and 98.2% respectively. And the V/Fe3O4 has good photocatalytic efficiency after several recycling tests in the acid reaction condition. [ABSTRACT FROM AUTHOR]

A series of CuMgFe layered double hydroxides (denoted as X/CuMgFe–LDHs) with different Cu contents were synthesized by co‐precipitation as catalysts for phenol hydroxylation under mild conditions. The as‐prepared samples were analyzed by X‐ray diffraction (XRD), scanning electron microscopy (SEM), inductively coupled plasma emission spectroscopy (ICP‐ES), N2 adsorption–desorption, Fourier transform infrared (FT‐IR), thermogravimetric differential scanning calorimetry (TG‐DSC), X‐ray photoelectron spectroscopy (XPS) and hydrogen temperature‐programmed reduction (H2‐TPR) to investigate the morphologies and physicochemical properties. As presented by the characterization results, introducing a certain amount of copper not only increased the amount of active metal centers but also formed more oxygen vacancies and lattice oxygen to promote electron transport between the double layers in LDHs. However, the excess copper would significantly disrupt the X/CuMgFe–LDH framework, declining the activity. Therefore, the 20/CuMgFe–LDH sample presented the best catalytic performance among all the catalysts in terms of activity, which was correlated with the layered structure, low‐temperature reducibility, oxygen species and low Cu+/Cu2+ and Fe2+/Fe3+ ratios. The catalyst could maintain good stability even after recycling for five times. Finally, a possible mechanism for phenol hydroxylation via Cu+–OV–Fe2+ and Cu2+–O–Fe3+ redox cycles on CuMgFe–LDHs was proposed. [ABSTRACT FROM AUTHOR]

An efficient amino‐acid‐mediated ipso‐hydroxylation of arylboronic acids, aryl boronate esters and aryl trifluoroborates to aryl alcohols has been described. The current protocol was realized by using sub‐stoichiometric amount of l‐histidine in presence of triethylamine under aerobic conditions in DMF as solvent. This amino‐acid‐mediated process provides an alternative route for the hydroxylation of organoborons through in situ generation of hydrogen peroxide. The present protocol explores the synthetic utility of amino acids as organocatalysts for the preparation of aryl alcohols. It was observed that l‐histidine plays an important role for the conversion of aerial oxygen in to hydrogen peroxide via thermal excitation process followed by thermal degradation of Et3N. The developed approach holds good for a wide range of compounds with excellent yields and competent functional group tolerance. [ABSTRACT FROM AUTHOR]

A practical synthetic strategy for the preparation of enantiomerically pure 3‐substituted pyroglutamic acid derivatives is described. This procedure pivots on fast 5‐exo‐tet cyclization of the chloroacetylated amino acids, prepared by the crystallization induced diastereomeric transformations (CIDT). Furthermore, oxidation of obtained 3‐substituted pyroglutamic acids afforded highly valuable scaffolds with a quaternary stereogenic center with excellent diastereoselectivity. The absolute stereochemical configuration of both, 3‐aroyl pyroglutamic acid and its 3‐hydroxylated derivative, was confirmed by single‐crystal X‐ray analysis. The versatility of the methodology is exemplified using a variety of aromatic and heteroaromatic amino acids. The efficiency of this chromatography‐free approach predestines it for the gram‐scale synthesis. This was demonstrated with the synthesis of more than 10 mmol of the model substrate with excellent overall yield and diastereoselectivity. [ABSTRACT FROM AUTHOR]

MOF‐5‐derived porous carbon (MDPC) materials, MDPC‐600 and MDPC‐1000, were prepared by pyrolysis at 600 °C in nitrogen atmosphere prior to acid treatment and at 1000 °C in nitrogen atmosphere, respectively. The samples were characterized by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), X–MaxN energy spectrum, and transmission electron microscopy (TEM). The test results of MDPC‐1000 and MDPC‐600 show that both are microporous amorphous carbon with the 2.7 nm diameter pore size, indicating that the micropore of MOF‐5 is well preserved during pyrolysis. MDPC‐1000 and MDPC‐600 have specific surface areas of 1570.9 m2/g and 1029.5 m2/g, respectively. MDPC‐1000 and MDPC‐600 were loaded with Fe ions to prepare Fe(III)/MDPC composite materials, which were used as catalysts for phenol hydroxylation. The results show that Fe(III)/MDPC‐1000 has higher catalytic effect than Fe(III)/MDPC‐600. During one hour phenol hydroxylation at 80 °C with 3 wt.% Fe concentration and a mass ratio of catalyst to phenol of 0.053, Fe(III)/MDPC‐1000 provides maximum phenol conversion, dihydroxybenzene yield, and dihydroxybenzene selectivity of 61.4%, 54.3%, and 88.4%, respectively. [ABSTRACT FROM AUTHOR]

A novel synthetic strategy of cascade C−H activation/C−S coupling/C−O cyclization reaction by using metal organic framework material Cu3(BTC)2 as catalyst is investigated. In this method, Cu3(BTC)2 can effectively catalyze the hydroxylation of the ortho‐Csp2‐H of benzenethiol, and then the coupling reaction and intramolecular C−O coupling cyclization. Phenoxathiine derivatives are efficiently prepared by one‐pot method. In our work, a series of phenoxathiin derivatives were obtained in good yield by this method. At the same time, the reaction mechanism was explored through conditional control experiments. [ABSTRACT FROM AUTHOR]

Crystal size and framework Ti content are two main factors which influence catalytic performances of TS‐1 catalysts. Control over the crystal size and framework Ti of TS‐1 through the synthesis of TS‐1 in the presence of polyethylene glycol (PEG) is reported. The crystal size of TS‐1 sample synthesized in the presence of PEG, TS‐1‐PEG was 230 nm. However, the size of TS‐1 synthesized without PEG, standard sample, was 290 nm. The TS‐1‐PEG possess higher amount of framework Ti content and less anatase TiO2 in comparison with TS‐1. The catalytic reaction tests showed superior activity of TS‐1‐PEG toward hydroxylation of phenol and oxidation of dibenzothiophene, deep desulfurization of fuels, as a result of cooperative effects of smaller particle size and higher framework Ti content. Consequently, using safe and un‐expensive PEG polymer is a powerful approach to synthesize TS‐1 with small crystal size and high framework Ti content to make efficient TS‐1 catalyst. [ABSTRACT FROM AUTHOR]

Improving the framework titanium (Ti) of titanium silicalite‐1 (TS‐1) zeolites and creating inter‐crystalline mesoporosity are two ways to enhance the catalytic properties of TS‐1 for hydroxylation of phenol. Most researches only used one of the ways. In this study, we successfully synthesized of hierarchical Titanium‐Rich (Ti‐rich) TS‐1. Ti‐rich TS‐1 was synthesized in the presence of ammonium carbonate ((NH4)2CO3). The framework Ti content of TS‐1 zeolites synthesized by different content of (NH4)2CO3 was studied by X‐ray fluorescence (XRF), Fourier transform infrared spectra (FTIR) and ultraviolet visible spectra, the framework Ti content was significantly increased by using (NH4)2CO3 as crystallization‐mediating agent. The synthesized samples were evaluated in hydroxylation of phenol. When the molar ratio of ammonium carbonate and tetraethyl orthosilicate in the synthesis gel was 0.2, the molar ratio of Si/Ti reached 34.43 and the Ti‐rich TS‐1 shows the optimum catalytic activity in hydroxylation of phenol. The post‐modification with aqueous solution of tetrapropylammonium hydroxide (TPAOH) was used to further improve the diffusion property. Compared with the parent TS‐1, the secondary pore volume was all increased. The developed hierarchical Ti‐rich TS‐1 zeolites were also assessed in hydroxylation of phenol. It was confirmed that hierarchical Ti‐rich titanium silicalite‐1 zeolites can improve the catalytic activity in phenol conversion considerably. Here, we have synthesized the hierarchical Titanium‐Rich TS‐1 zeolites using (NH4)2CO3 as a crystallization‐mediating agent and TPAOH as mesoporous structure direction. The phenol conversion, dihydroxybenzene selectivity and H2O2 efficiency were all increased compared to the conversional TS‐1 zeolites [ABSTRACT FROM AUTHOR]

A new Fe(III)/MOF‐5(Ni) catalyst with high hydrostability was prepared using an equal load method under room temperature, and nearly 100% selectivity for catechol and 63.2% yield of dihydroxybenzene were obtained in hydroxylation of phenol with H2O2 over Fe(III)/MOF‐5(Ni) catalyst. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites designed especially for catalytic application is a relatively unexplored domain in material chemistry as well as synthetic organic chemistry. The current work strives on crafting high performance hyperbranched polymer nanocomposites with catalytic properties for direct organic transformations. Herein, a bio‐derived aliphatic hyperbranched polyurethane (HPU) was fabricated with bimetallic palladium‐silver‐carbon dot (Pd−Ag@CQD) nanohybrid by in situ polymerization technique. Different compositions of the nanocomposite were prepared by varying the loading of nanohybrid. Analytical techniques like FT‐IR, PXRD, TEM, TGA and DSC were utilized for characterization of the nanocomposites. The bimetallic nanohybrid in unison with carbonaceous CQDs was found to be poly‐dispersed in the HPU matrix. The combination of the bimetallic‐cum‐carbonaceous nanohybrid with HPU provided significant improvement of mechanical properties like tensile strength (2.2 fold), elongation at break (1.19 fold), toughness (3.0 fold) etc. over pristine HPU. The bimetallic nanohybrid‐supported nanocomposites also demonstrated vastly enhanced thermal stability (above 300 °C). The nanocomposites demonstrated loading‐dependent enhancement of mechanical and thermal properties. The HPU‐supported Pd−Ag@CQD nanocomposite displayed exceptional efficiency (100% conversions, 30–60 min) as a robust and recyclable catalyst (upto 10 cycles) for rapid oxidative ipso‐hydroxylation of aryl boronic acids to yield corresponding phenols. The poly‐dispersion of Pd−Ag@CQD in HPU offered multiple nano‐reactive sites, while superior mechanical properties of HPU‐supported bimetallic nanocomposites provided stability, heterogeneity and sustainability. The current catalytic protocol presents a facile route for preparation of phenols and its derivatives and can be suitable for opening up new avenues for large‐scale applications. Hyperbranched polyurethane‐supported bimetallic‐cum‐carbonaceous Pd−Ag@CQD nanocomposite was fabricated by in situ polymerization. The nanocomposite demonstrated high mechanical properties and efficient catalytic activity towards rapid oxidative conversion of aryl boronic acids to phenols. [ABSTRACT FROM AUTHOR]

In this work, we used a metal organic framework of PCN‐6', which prepared from copper compound and iazine‐2,4,6‐triyl‐benzoate (H3TATB) ligand, to catalyze the disulfide reacted with aryl iodide and sulfonyl chloride to synthesize of sulfonyl diphenylsulfides. A series of sulfonyl diphenylsulfide derivatives were synthesized with medium or high yields. [ABSTRACT FROM AUTHOR]

Abstract: Cp*RhIII‐catalyzed selective C7‐hydroxylation and acetoxylation reactions of indolines under mild conditions have been developed. The reactions are directed by a removable pyrimidyl group and have high functional group tolerance. It provides a mild access to hydroxylated and acetoxylated indolines in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

Abstract: The β‐hydroxy‐γ‐lactones, cardiobutanolide and Hagen's gland lactones have been interesting targets for total synthesis in many laboratories. There are 10 syntheses reported for cardiobutanolide and 19 syntheses for Hagen's gland lactones. These natural products have the β‐hydroxy‐γ‐lactone moiety in common. The evolution of various synthetic strategies to these natural products from chiral pool materials and/or asymmetric catalysis and involving linear sequences, convergent approaches to the de‐novo protecting group free syntheses have been abstracted in this review. [ABSTRACT FROM AUTHOR]