White Portland cement is an ideal choice for producing 3D printed coloured composites due to its inherent whiteness. However, the uncontrollable rheological properties limit establishment of structures and thus affect mechanical properties. In this study, polyvinyl alcohol (PVA) polypropylene (PP) fibres were utilised as reinforcement materials in white (WPCCs) improve printability toughness by controlling creep properties, aiming build better structures. Experimental results show that...

The direct coupling of aryl halides to prepare symmetrical and unsymmetrical biaryls were performed successfully in poly(ethylene glycol) (PEG) using Pd(OAc)2 as the catalyst absence other additives or reductants. selectivity toward biaryl depended on amount PEG used. Excessive PEGs induce increase hydrodehalogenation product, best is obtained when concentration hydroxyl group achieves 100 mol % relative halides. system could be recycled reused up five times with no loss catalytic activity.

Abstract The cascade [1,n]‐hydrogen transfer/cyclization, recognized one century ago, has received considerable interest in recent decades and great achievements have been made. This process can functionalize C( sp 3 )H bonds directly into CC, CN, CO under the catalysis by Lewis acids, Brønsted acids or organocatalysts, even thermal conditions. methodology shown preeminent power to construct 5‐ 6‐membered heterocyclic as well all‐carbon rings. In this review, various hydrogen donors...

Abstract Alkylideneindoleninium ions and alkylideneindolenines generated from 3‐substituted indoles are important intermediates in organic synthesis, which can be trapped by a large variety of nucleophilic reagents to construct biologically 3‐indolyl derivatives. This Focus Review summarizes the recent developments asymmetric syntheses derivatives via alkylideneindoleninium or alkylideneindolenines. The elimination mechanism leaving groups strategies discussed.

An efficient dehydrative S_N1-type reaction of indolyl alcohols with diverse nucleophiles was developed using water as the solvent, affording versatile 3-indolyl derivatives in high yields. The advantages being catalyst-free, environmentally benign, and wide substrate scope make it a promising method for preparation compounds.

Carbocation-initiated cascade [1,5]-hydride transfer/cyclization and dimerization reactions were developed to synthesize dihydrodibenzo[b,e]azepine octahydrodipyrroloquinoline derivatives in high yields. These redox-neutral C(sp3)-H functionalization-involving feature transition-metal-free, atom- step-economy, environmental friendliness with water as the sole byproduct.

The catalyst-free sp3 C–H functionalization of 2-alkylazaarenes has been achieved in the reaction with (thio)coumarin-3-carboxylic acids. Followed by a tandem decarboxylation, this method provides facile synthesis biologically important azaarene-substituted 3,4-dihydro(thio)coumarins single step high yields.

Abstract The first total syntheses of schilancitrilactones B and C have been accomplished in 17 steps (longest linear sequence) from commercially available materials. Key include an intramolecular radical cyclization to provide the seven‐membered ring, late‐stage iodination, intermolecular addition reaction complete synthesis.

Water enabled a highly atom- and step-economical, redox-neutral 4-step cascade process, including S_NAr/Knoevenagel condensation/[1,5]-hydride transfer cyclization, to construct pharmaceutically important tetrahydroquinoline spiro compounds efficiently.

The pharmaceutically intriguing spiroindolenines incorporating tetrahydroquinoline were constructed via a hexafluoroisopropanol-promoted redox-neutral cascade cyclization from readily available starting materials. benzazepinoindole skeletons could also be facilely accessed one-pot sequential operation. Distinctive features of these transformations include their controllable access the two privileged skeletons, high efficiency, simple operation, and mild reaction conditions.

[3,4]-Fused oxindoles are the core structures of naturally occurring oxindole alkaloids, and fused tricyclic have distinguished themselves with unique biological activities. Herein, we developed a synthetic strategy for divergent synthesis diverse types [3,4]-seven- or six-membered ring-fused 3-alkenyl-oxindoles incorporating benzazepine significant building blocks from propargyl alcohols via cascade nucleophilic substitution/site-selective hydride transfer/cyclization process...

This review highlights the encouraging advances in hydride transfer-involved dearomatization reaction during past decade, content of which is categorized according to acceptors, namely vinylogous imines and quinone methides.

The Brønsted acid-controlled switchable synthesis of indoline-fused tetrahydroquinolines and indole-fused benzazepines was developed through hydride transfer-enabled formal [5 + 1] 2] cyclization reactions from indoles N-alkyl o-aminobenzoketones. Indoline, furanone, tetrahydroquinoline hybridized pentacyclic products were unprecedentedly accessed via a cascade condensation/hydride transfer/dearomatization-cyclization/deethylation/nucleophilic addition process. In addition, the undeveloped...

The H 2 O-promoted controllable synthesis of diverse 3-carboxyl and 3-acyl substituted tetrahydroquinolines 3,4-dihydroquinolin-2(1 )-ones from readily available feedstocks was developed by a hydride transfer strategy.

The preparation of FSG-supported palladium nanoparticles and their application in direct C-2 arylation indoles are presented. Moderate to good yields were obtained with ultra-low catalyst loading. could be easily recovered by simple workup reused up seven runs only a slight decrease its activity.

A metal- and base-free protocol for one-pot synthesis of 2,5-diaryl 1,3,4-oxadiazoles via a radical-promoted cross-dehydrogenative coupling strategy was developed. This reaction involved the N-acylation aryl tetrazoles with aldehydes, followed by thermal rearrangement. wide range aldehydes survived conditions to deliver corresponding products in moderate good yields.

The switchable synthesis of 3-non, 3-mono, 3,3′-disubstituted 3,4-dihydroquinolin-2(1H)-ones was developed through a redox-neutral hydride-transfer/N-dealkylation/N-acylation strategy from o-aminobenzaldehyde with 4-hydroxycoumarin, and Meldrum's acid, respectively. unprecedented for the 3,3′-highly functionalized 3,4-dihydroquinolin-2(1H)-one has been realized in situ utilization released HCHO via o-QM involved Michael addition. In addition, synthetic utility this protocol well illustrated...

Gut homeostasis is critical for human health, ulcerative colitis (UC) can disrupt gut and cause disease. Panax ginseng C.A. Meyer a widely used traditional herbal medicine known its anti-inflammatory, antioxidant, immunomodulatory effects. However, the protective mechanisms of total ginsenosides (TG) in treating UC remain unclear. In this study, we employed Drosophila melanogaster as model organism to investigate effects TG on dextran sulfate sodium (DSS)-induced intestinal injury. Our data...

A transition-metal-free synthetic approach for constructing alkylated aryl tetrazoles has been developed using n-Bu4NI as the catalyst and t-BuOOH oxidant. It involves direct C–N bond formation through sp3 C–H activation. wide range of benzylic substrates (or alkyl ethers) undergo this reaction smoothly to deliver corresponding products in good yields.

The tandem Michael addition/decarboxylation of (thio)-coumarin-3-carboxylic acids with indoles gives biologically important indole-3-substituted dihydrocoumarins in good to excellent yields under catalyst-free conditions.

The electronic effect and steric have a dramatic impact on the fascinating cascade [1,<italic>n</italic>]-hydride transfer/cyclization. regioselectivity of two potential hydrogen donors could be perfectly tuned to construct different skeletons.

Herein we demonstrate simply that the addition of Pd(OAc)2 as a promotor switches reactivity commonly used base NaH to nucleophilic reductant. The is engineered into palladium-catalyzed reductive debenzylation and deallylation aryl ethers esters. This operationally simple, mild protocol displays broad substrate scope spectrum functional group tolerance (>50 examples) high chemoselectivity toward over aliphatic structures. Moreover, dual reductant demonstrated in efficient synthetic elaboration.