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Designing novel electropolymerizable monomers is essential in developing electron donor-electron acceptor (D-A) type conjugated polymers for applications in sensing, catalysis, and energy storage. Thiophene and pyridine-substituted quinoline-based molecules (Th-Q, DTh-Q, and Py-Q) are synthesized in this work, and their crystal structures, optical properties, and electrochemical properties are investigated. The potentiostatic electropolymerization of these molecules are successfully carried out on carbon cloth substrate, with the thiophene and quinoline as the possible electropolymerizable units. The PTh-Q shows the best charge storage performance ( 1.12 × 10 − 3 C at 0.02 mA cm-2 in the potential range of 0-1 V) in 0.1 M Na2SO4, and maintains 77% of the initial capacity after 3000 charge-discharge cycles at 0.02 mA cm-2. The morphology and structure of the PTh-Q does not alter significantly after the repetitive charge-discharge cycling. The superior charge storage performance of the PTh-Q than PDTh-Q and PPy-Q is originated from the exposed highest amount of electrochemically active sites and the participation of redox processes of both hydroxyl/ketone structures on quinoline and thiophene groups.

A mild Ru(0)-catalyzed cleavage of C(aryl)–O bonds enabled by a combination of a Ru3(CO)12 catalyst and an imine auxiliary is reported.

Direct functionalization of the C(O)–N amide bond is one of the most high-profile research directions in the last few decades; however oxidative couplings involving amide bonds and functionalization of thioamide C(S)–N analogues remain an unsolved challenge.

An AIE-active Schiff base was available for indicator paper and cell imaging applications for the successive identification of Cu2+ and His.

Herein, we disclose a novel reorganization/cycloaddition between two imine units catalyzed by In(OTf)3 Lewis acid that differs from the well-known [4 + 2] cycloaddition version via the Povarov reaction.

We propose an intramolecular synergistic counteracting strategy of fluorescence resonance energy transfer and the inner filter effect for accurate photoactivation monitoring, to eliminate the influence of the biological microenvironment.

Divergent deaminative and denitrative C–N cleavages and cascade transformations using amines and nitroalkanes have been developed under a highly effective and environmentally-friendly catalytic system (RuCl3/TFE).

A D-π-A type quinoline derivative, 2-(((4-(1, 2, 2-triphenylvinyl)phenyl)imino)methyl)quinolin-8-ol (

The direct synthesis of ketones via acyl Suzuki-Miyaura cross-coupling of widely available acyl chlorides is a central transformation in organic synthesis. Herein, we report the first mechanochemical solvent-free method for highly chemoselective synthesis of ketones from acyl chlorides and boronic acids. This acylation reaction is conducted in the solid state, in the absence of potentially harmful solvents, for a short reaction time and shows excellent selectivity for C(acyl)-Cl bond cleavage.

We present a general strategy for activation of N–C(S) thioamide bonds by ground-state-destabilization in the context of a full study on transamidation of thioamides with nucleophilic amines.

Chemodivergent control in the functionalization of nitrogen-directed aromatic C–H bonds has been achieved by a switchable catalyst.

In this article, a novel triphenylamine-modified salicylaldehyde Schiff base 2-(((4-(diphenylamino)phenyl)imino)methyl)-4-(pyridine-4-yl)phenol (HL) was synthesized and structurally characterized. HL possessed D-π-A structure and exhibited typical AIE property in THF/H

Reorganization of unsaturated chemical bonds is one of the most promising strategies to generate architecturally diversified and innovative molecular library. Herein, we disclose a novel reorganization/cycloaddition between two imine units catalyzed by In(OTf)3 Lewis acid, which is sharply distinguished from the well-recognized [4+2] cycloaddition version with Povarov reaction. By means of this unprecedented imine chemistry, a collection of synthetically useful dihydroacridines have been synthesized with high functional group compatibility under concise reaction conditions. Preliminary mechanistic studies unravel that α，β-unsaturated imine likely serves as a pivotal intermediate. Notably, handing products give rise to a series of structurally novel and fine-tuneable acridinium photocatalysts, which offers a heuristic paradigm for synthesizing these ones and is also highlighted by facilitating several encouraging dihydrogen coupling reactions efficiently.

Chemical transformation with vinylene carbonate as an emerging synthetic unit has recently attracted considerable attention. This report is a novel conversion pattern with vinylene carbonate, in which such a vibrant reagent unprecedentedly acts as a difunctional coupling partner to complete the C-H annulation of free anilines. From commercially available substrates, this protocol leads to the rapid construction of synthetically versatile 2-methylquinoline derivatives (43 examples) with excellent functionality tolerance.

Here we report a novel Rh-catalyzed C-H/C-H alkenylation of N-arylmethanimines with vinylene carbonate acting as a vinylene unit. Forty examples of C3,C4-nonsubstituted quinolines were achieved from commercially available starting materials. This identified process features an exceedingly simple system, a lower loading of catalyst, and the capacity for postfunctionalization with bioactive molecules.

Transition metal phosphides (TMPs) are regarded as highly efficient electrocatalysts due to highly active surface sites, electrical conductivity, and chemical stability, which result from the high electrocatalytic activity of the M-centers and P-sites. Thus, the aim of our work is to obtain highly efficient TMPs electrocatalysts by a facile and controllable strategy. We used N, S-rich Co/Fe bimetallic metal-organic framework as template to prepare ceramic Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix (CoFeP@NSOC). By means of a facile one-step low-temperature pyrolysis-phosphating approach, the optimized ceramic material CoFeP@NSOC-400 showed remarkable bifunctional electrocatalytic performances in an alkaline electrolyte, which only requires 176 and 240 mV overpotentials to achieve 10 mA cm−2 current density for HER and OER, respectively. Furthermore, when CoFeP@NSOC-400 is loaded on the highly conductive nickel foam (NF) for water splitting, it reaches a current density of 10 mA cm−2 at a low cell voltage of 1.62 V, superior to pure NF and other reported metal-phosphide electrocatalysts, at the same time, CoFeP@NSOC-400 shows negligible performance degradation and a relative current loss of only 4.3% for 40000 s continuous operations. These results indicate CoFeP@NSOC derived by MOFs through pyrolysis-phosphating is an ideal electrocatalysts for energy conversion applications.

We report palladium–BIAN–NHC chloro dimer complex, [Pd(BIAN–IPr)(μ-Cl)Cl]2. This rapidly activating catalyst merges the reactive properties of palladium chloro dimers, [Pd(NHC)(μ-Cl)Cl]2, with the attractive structural features of the BIAN framework.

We report a new copper-catalyzed [2 + 2 + 1] annulation process through the selective cleavage of sigma and triple C-C and C-H bonds using two ynone units. This new methodology involves breaking multiple chemical bonds in a single operation, including C≡C, C-C, C-H, and N-O. These high-value adducts lead to a diverse collection of synthetically challenging trisubstituted indolizines by the simultaneous engagement of different bond-breaking events and show excellent fluorescence in green aqueous solutions.

A rhodium(III)-catalyzed formal C–H [5 + 1] cyclization of 2-pyrrolyl/indolylanilines with vinylene carbonate has been explored towards the potent assembly of diverse 4-methylpyrrolo[1,2-a]quinoxalines. This established protocol is characterized by an exceedingly simple reaction system, and excellent functional group toleration and yields. Most importantly, entirely distinct from documented [4 + 2] cyclization conversions, herein, the emerging vinylene carbonate firstly presents as a C1 synthon to realize [5 + 1] annulation and shows new chemical reactivity. Biological studies indicate that these prepared products are promising candidates in terms of their antibacterial activity.

A zinc-catalyzed C–H alkenylation of quinoline N-oxides with ynones has been developed to rapidly assemble a broad collection of valuable quinoline-enol organic architectures. Uncommonly, this novel reaction involves C–H functionalization, and N–O, C–C and CC bond cleavage in one operation, and leads exclusively to the formation of an enol rather than a keto product. Application of the enols generated was highlighted by further derivative transformation and preparation of a series of “BODIPY” analogues with high quantum yields (up to 86%).

An acid-functionalized ionic liquid (IL)-catalyzed cascade decarboxylative cyclization of 2-arylanilines with α-oxocarboxylic acids was developed. This approach offered a sustainable and practical pathway to afford a library of quinoxalines in water under ambient conditions. This protocol tolerated various kinds of functional groups and could be easily scaled-up. The developed method featured a recyclable catalytic system, environmentally friendly reaction conditions, simple operation, and a practical workup procedure, which represented the potential to streamline quinoxaline synthesis in industry. A possible mechanism involving a dual activation strategy to promote both decarboxylation and cyclization processes was proposed.

The thioamide group represents a highly attractive isostere of the amide bond. We report a combined structural and computational study on cis-thioamide conformation of N-thioacyl-N-methylanilines. Amide to thioamide replacement in a class of anilides that are highly valuable as conformational locks results in a higher preference for cis conformation in a unique compacted template intrinsic to the thioamide structure. The study strongly supports the use of N-methylthioanilides as cis-conformational locks in various facets of chemistry.

Ruthenium(II)-catalyzed ortho-C-H alkylation of naphthylamines with diazo compounds for the synthesis of 2,2-disubstituted π-extended 3-oxindoles has been developed. The method represents the first example of C-H alkylation via carbenoid insertion in water as a sustainable solvent. The procedure includes an inexpensive ruthenium catalyst as well as aqueous media and results in the release of benign N2. The π-extended 3-oxindole products exhibit favorable antitumor properties and remarkable fluorescent properties in aqueous solution for fluorescent imaging.

Over the last 20 years, N-heterocyclic carbenes (NHCs) have emerged as a dominant direction in ligand development in transition-metal-catalysis. In particular, strong σ-donation in combination with tunable steric environment make NHCs to be among the most common ligands used for C–C and C–heteroatom bond formation. Thus far, NHC ligand development has been almost exclusively limited to N-aryl-imidazolylidenes, such as IPr, prepared by deprotonation of symmetrical imidazolium salts. However, the molecular structure of imidazolylidene systems is constrained by the substitution with two nitrogen atoms, a limitation that prohibits the development of more active carbene 2 analogues. Herein, we report the first study on steric and electronic properties of thiazol-2-ylidenes. We demonstrate that the ring dissymmetry and enhanced 𝝅-electrophilicity result in a class of highly active carbene ligands for electrophilic cyclization reactions to form valuable oxazoline heterocycles. The evaluation of steric, electron-donating and 𝝅-accepting properties as well as structural characterization and coordination chemistry is presented. This mode of catalysis can be applied to late-stage drug functionalization to furnish attractive building blocks for medicinal chemistry. Considering the key role of N-heterocyclic ligands, we anticipate that N-aryl thiazol-2-ylidenes will be of broad interest as ligands in modern chemical synthesis.

Blueberry anthocyanins have received increasing attention for their remarkable antioxidant, vision improvement, anti-inflammatory and cardiovascular disease prevention properties. However, the application of blueberry anthocyanins is limited due to their instability and the difficulty in absorption and utilization by the human body. This review provides a comprehensive summary of the species of blueberry (genus Vaccinium), the distribution of those species and the bioactivity of blueberry anthocyanins. Furthermore, the current review discusses the applications of blueberry anthocyanin-rich extracts, challenges in their application, and strategies to improve their bioavailability in the process of further development in the food and nutrition industry.

Although cross-coupling reactions of amides by selective N-C cleavage are one of the most powerful and burgeoning areas in organic synthesis due to the ubiquity of amide bonds, the development of mechanochemical, solid-state methods remains a major challenge. Herein, we report the first mechanochemical strategy for highly chemoselective, solvent-free palladium-catalyzed cross-coupling of amides by N-C bond activation. The method is conducted in the absence of external heating, for short reaction time and shows excellent chemoselectivity for σ N-C bond activation. The reaction shows excellent functional group tolerance and can be applied to late-stage functionalization of complex APIs and sequential orthogonal cross-couplings exploiting double solventless solid-state methods. The results extend mechanochemical reaction environments to advance the chemical repertoire of N-C bond interconversions to solid-state environmentally friendly mechanochemical methods.

Here we report a novel Rh-catalyzed C-H/C-H alkenylation of

This work reports a simple and ecofriendly way of recycling polyethylene terephthalate (PET) waste. PET waste was glycolyzed using trimethylolpropane (TMP) giving tetra-functional glycolyzate, to prepare alkyd resin. 0.25% ZnOAc and the TMP to PET molar ratio of 12:1 at 220 °C produced the best yield of glycolyzate. The obtained glycolyzate was characterized by Fourier transform infrared spectroscopy (FTIR) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) and further used in the synthesis of alkyd resins. The properties of the prepared alkyd resins including acid value, the pencil hardness, chemical resistance and thermal stability, were investigated. The pencil hardness of the cured resins film is 3H, which is better than the commercial alkyd resin YF-155. Thermogravimetric analysis (TGA) exhibited polymer decomposition occurred above 160 °C. When compared to commercial coatings, Zanthoxylum bungeanum seed oil (ZSO)-based alkyd resin from postconsumer PET bottles has potential for commercial applications, and may even be superior in thermal and chemical resistance.

We report the synthesis of C6-substituted isoquinolino[1,2-b]quinazolinones via rhodium(III)-catalyzed C-H annulation with sulfoxonium ylides and evaluation of the cytotoxic activity of the scaffold. This C-H activation approach enables the most straightforward and convergent synthesis of C6-substituted isoquinolino[1,2-b]quinazolines reported to date. This operationally simple method is compatible with a wide variety of the sulfoxonium ylide and arene C-H activation coupling partners, permitting access to diverse isoquinolino[1,2-b]quinazolines. This method shows a high atom economy, generating H2O and dimethyl sulfoxide (DMSO) as by-products. This method is scalable and operates with exquisite N-lactam cyclization selectivity, thus enabling expedient access to new heterocyclic analogues featuring promising cytotoxic properties.

Waterborne alkyd resins based on Zanthoxylum bungeanum seed oil modified with epoxy resin were prepared by polyesterification reaction. The different base catalysts were examined on the alcoholysis reaction. Further, epoxy-modified waterborne alkyd resins were blended with hexamethoxy methyl melamine to improve the properties like curing time, chemical resistance and thermal stability. The properties of the prepared resins (acid value, drying time, pencil hardness, adhesion, flexibility, chemical resistance and thermal stability) were studied. The prepared polymers were characterized by FT-IR spectroscopy, particle size analysis and thermogravimetric analysis. ZSO-based alkyd resins modified epoxy resin and their blends with HMMM (EWA:HMMM = 3:1) showed enhanced chemical resistance, physical properties and thermal stability.

Rhodium(III)-catalyzed C–H amidation of 2-arylindoles with dioxazolones for the synthesis of indolo[1,2-c]quinazolines is reported. The reaction is compatible with a wide range of electronically diverse 2-arylindoles and dioxazolones, providing indolo[1,2-c]quinazolines in high to excellent yields. Most notably, the combination of this Rh-catalyzed C–H amidation and intramolecular N–H/N–C(O) cyclization enables the most straightforward direct route to indolo[1,2-c]quinazolines to date. Mechanistic studies and evaluation of antitumor activity of these high value heterocycles are disclosed.

A novel [5 + 1] cyclization of 2-vinylanilines with polyfluoroalkanoic acids under catalyst- and additive-free conditions was successfully implemented. The approach directly employs very low-cost and readily available polyfluoroalkanoic acids as both C1 synthons and fluoroalkyl building blocks. This method provides concise access to diverse 2-fluoroalkylated (CF3, C2F5, C3F7, CF2H, CF2Cl, and CF2Br) quinolines in good yields with excellent functional group tolerance in high yield on a gram scale.

A metal-free C–H [5 + 1] annulation reaction of 2-arylanilines with diazo compounds has been achieved, giving rise to two types of prevalent phenanthridines via highly selective C–C cleavage. Compared to the simple N–H insertion manipulation of diazo, this method elegantly accomplishes a tandem N–H insertion/SEAr/C–C cleavage/aromatization reaction, and the synthetic utility of this new transformation is exemplified by the succinct syntheses of trisphaeridine and bicolorine alkaloids., A metal-free C–H [5 + 1] annulation reaction of 2-arylanilines with diazo compounds has been achieved, giving rise to two types of prevalent phenanthridines via highly selective C–C cleavage.

A zinc-catalyzed C-H alkenylation of quinoline N-oxides with ynones has been developed to rapidly assemble a broad collection of valuable quinoline-enol organic architectures. Uncommonly, this novel reaction involves C-H functionalization, and N-O, C-C and C[triple bond, length as m-dash]C bond cleavage in one operation, and leads exclusively to the formation of an enol rather than a keto product. Application of the enols generated was highlighted by further derivative transformation and preparation of a series of "BODIPY" analogues with high quantum yields (up to 86%).

A novel metal-free C-H [5 + 1] carbonylative annulation of 2-alkenyl/pyrrolylanilines with dioxazolones has been established for the assembly of the privileged quinolinones and pyrrolyl-fused quinoxalinones. Entirely differing from the existing reports, the dioxazolones herein behave with an innovative chemistry and first emerge as carbonylating reagents to participate in annulation reactions. Moreover, this process features exceedingly simple operation (only solvent) and tolerates both vinyl and aryl substrates. Comprehensive mechanistic studies indicate that the formed isocyanate intermediate plays a crucial role in enabling the carbonylation annulation.

We report a new copper-catalyzed [2 + 2 + 1] annulation process through the selective cleavage of sigma and triple C-C and C-H bonds using two ynone units. This new methodology involves breaking multiple chemical bonds in a single operation, including C≡C, C-C, C-H, and N-O. These high-value adducts lead to a diverse collection of synthetically challenging trisubstituted indolizines by the simultaneous engagement of different bond-breaking events and show excellent fluorescence in green aqueous solutions.

The thioamide group represents a highly attractive isostere of the amide bond. We report a combined structural and computational study on

A highly chemoselective domino condensation/aza-Prins cyclization/retro-aldol between 2-alkenylanilines with β-dicarbonyl compounds under metal-free conditions was accomplished, giving a large category of valuable 2-substituted quinolines in good yields with excellent functional group toleration. This newly established process, adopting β-ketoesters as masked C1 synthons via C-C cleavage, could even be simplified into a three-component [3 + 2 + 1] domino version consisting of exceedingly low-priced commercial starting materials. The synthetic application of products was exemplified by several intriguing chemical operations.