Cu-catalyzed cyclizations of (E)-O-propargylic oximes alpha,beta-unsaturated aldehydes were successfully carried out to afford the corresponding pyridine oxides in good high yields. As an example, (E)-acrylaldehyde O-1,3-diphenylprop-2-ynyl oxime (1b) was reacted for 5 h presence CuBr(PPh(3))(3) (10 mol %) and PPh(3) DMSO at 120 degrees C 3-benzyl-2-phenylpyridine-N-oxide (2b) 84% yield. In this case, reaction proceeded via propargyl oxime-allenyl nitrone rearrangement followed by...

4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) is an important target site for discovering new bleaching herbicides. To explore novel HPPD inhibitors with excellent herbicidal activity, a series of N-aroyl diketone/triketone derivatives were rationally designed by splicing active groups and bioisosterism. Bioassays revealed that most these displayed preferable activity against Echinochloa crus-galli (EC) at 0.045 mmol/m2 Abutilon juncea (AJ) 0.090 mmol/m2. In particular, compound...

Stimuli-responsive hybrid nanoparticles used for controllable catalysis have been attracting increasing attention. This study aims to prepare microgels with excellent temperature-sensitive colorimetric and catalytic properties through combining the surface plasmon resonance of gold (AuNPs) poly(N-isopropylacrylamide) (PNIPAM)-based microgels. Microgels hydroxy groups (MG-OH) were prepared by soap-free emulsion polymerization, using N-isopropylacrylamide as main monomer, hydroxyethyl...

An efficient and green electrochemical N-ortho-selective difluoromethylation method of various quinoline isoquinoline N-oxides has been developed. In this method, sodium difluoromethanesulfinate (HCF2SO2Na) was used as the source difluoromethyl moiety, were obtained in good to excellent yields under a constant current. addition, reaction easy scale up maintained yield. Preliminary mechanism studies suggested that undergoes free-radical addition hydrogen elimination pathway.

A novel method for the synthesis of functionalized azepine derivatives has been developed through a phosphine-catalyzed [4 + 3] annulation β′-acetoxy allenoates with benzimidazole-derived 1C,3N-dinucleophiles. This approach demonstrates high efficiency and yields ranging from moderate to excellent. The reaction exhibits wide substrate scope under optimized conditions. Furthermore, an initial exploration asymmetric variant this conducted, utilizing phosphine (R)-SITCP as catalyst.

(E)-O-Propargylic arylaldoximes were regioselectively converted, in the presence of copper catalysts, into their corresponding four-membered cyclic nitrones good to excellent yields. The reactions proceeded via a tandem [2,3]-rearrangement and 4π-electrocyclization N-allenylnitrone intermediate involved cleavage carbon–oxygen bond.

Copper-catalyzed skeletal rearrangement of <i>O</i>-propargylic aryloximes (<i>E</i>)-<b>1</b> were carried out to afford the corresponding four-membered cyclic nitrones <b>2</b> in good excellent yields. The optimal reactions conditions highly regioselective involved use [CuCl(cod)]₂ acetonitrile at 70 °C. In case (<i>Z</i>)-<b>1</b>, however, reaction proceeded absence copper catalysts identical compound Furthermore, also using chiral substrates (<i>R</i>)-<b>1</b> presence Cu...

Design of pyrazole benzophenones as potent HPPD inhibitors with excellent herbicidal activities.

We have developed a new oxidative decarboxylation of cinnamic acids with 4-alkyl-1,4-dihydropyridines to construct C(sp3)-C(sp2) bonds in the presence copper catalyst and dicumyl peroxide (DCP). A variety internal alkenes been obtained mild conditions, broad substrate scope excellent functional group tolerance. This method has significant potential for application by using inexpensive stable instead alkenyl halides nitro-olefins.

Direct radical-mediated reductive coupling of nitroarenes with 4-alkyl-1,4-dihydropyridines to build the C(sp 3 )–N bond using as internal reducing agents and alkyl sources is presented.

ADVERTISEMENT RETURN TO ISSUEPREVNoteNEXTSynthesis and Solubility of (Mono-) End-Functionalized Poly(2-hydroxyethyl methacrylate-g-ethylene glycol) Graft Copolymers with Varying Macromolecular ArchitecturesDong Zhang, Celia Macias, Christine OrtizView Author Information Department Materials Science Engineering, Massachusetts Institute Technology, 77 Avenue, Cambridge, 02139 Cite this: Macromolecules 2005, 38, 6, 2530–2534Publication Date (Web):February 18, 2005Publication History Received5...

O-Propargylic oximes that possess a proton at the α-position of oxime group were effectively converted to corresponding oxiranyl N-alkenylimines via 5-endo-dig cyclization followed by cleavage N–O bond.

An efficient method for the preparation of difluoromethylated benzothiophenes via visible-light-mediated alkyne difunctionalization was developed. In this method, inexpensive sodium difluoromethanesulfinate (HCF

A series of novel sulfonylurea benzothiazolines was designed by splicing active groups and bioisosterism. solvent-free synthetic route developed for the benzothiazoline derivatives via cyclization carbamylation. All compounds were characterized IR, ¹H-NMR, 13C-NMR, HRMS. The biological activity tests indicated could protect maize against injury caused chlorsulfuron to some extent. molecular docking result showed that new compound competed with bind herbicide target enzyme site attain detoxification.

B(C 6 F 5 ) 3 -catalyzed cross-coupling reaction between allylic alcohols and boronic acids with excellent regioselectivity, broad scope mild conditions.

<italic>O</italic>-Homoallenylic α,β-unsaturated oximes were efficiently converted to the corresponding 2-alkenylpyridine derivatives by microwave irradiation.

A novel and green method for the synthesis of 3-thiocyanatobenzothiophenes via electrochemical-oxidation promoted difunctionalization active alkyne has been developed. In this protocol, inexpensive easily available potassium thiocyanate was chosen as thiocyanation reagent, 2-alkynylthioanisoles substrates, a variety were obtained in moderate to good yields under oxidant- catalyst-free conditions. Moreover, continuous flow system applicability transformation, use overcome disadvantage low...

A simple and mild approach for the synthesis of α‐ketothioesters via 1,3‐Dibromo‐5,5‐dimethylhydantoin (DBH)/DMSO mediated oxidative thioesterification alkenes has been developed. Various products were produced in moderate to good yields under metal‐free conditions. And this method features readily available starting materials broad substrate scope. Moreover, a plausible mechanism was proposed based on methyl bromide captured experiment.

Dihydroartemisinin (DHA) is the first generation of artemisinin derivatives with antimalarial activity 10 times higher than and recurrence rate as low 1.95%. Since DHA was developed marketed a new drug in 1992, Tu Youyou’s group has been paying attention to explore clinical indications DHA. The project for treatment lupus made great progress, which preclinical studies have completed application its trials approved by SFDA 2016. Lupus erythematosus (LE) chronic autoimmune disease human immune...

A green and efficient electrochemical method for the preparation of difluoromethylated indoles has been developed. In this work, sodium difluoromethanesulfinate (HCF2SO2Na) was used as fluorinating reagent, various indole derivatives with difluoromethylation at C-2 position were obtained in moderate to good yields under catalyst- oxidant-free conditions. Moreover, protocol is operationally simple, proceeds room temperature, can be easily scaled up. Cyclic voltammetry (CV) control experiments...

Unexpected reaction of enethiols to form 1,3-dithiolanes and mixed disulfides in DMSO occur through a common thioketone intermediate.