A5004016253- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Catalytic C–H Functionalization Methods
- Asymmetric Synthesis and Catalysis
- Physics of Superconductivity and Magnetism
- Synthesis and Catalytic Reactions
- Cyclopropane Reaction Mechanisms
- Catalytic Alkyne Reactions
- Magnetic properties of thin films
- Synthesis and Biological Evaluation
- Asymmetric Hydrogenation and Catalysis
- Crystallography and molecular interactions
- Quinazolinone synthesis and applications
- Chemical Synthesis and Analysis
- Luminescence and Fluorescent Materials
- Molecular Sensors and Ion Detection
- Synthesis and Reactions of Organic Compounds
- Sulfur Compounds in Biology
- Force Microscopy Techniques and Applications
- Oxidative Organic Chemistry Reactions
- Pesticide Residue Analysis and Safety
- Synthetic Organic Chemistry Methods
- Sulfur-Based Synthesis Techniques
- Mechanical and Optical Resonators
- Pharmacological Effects and Assays
Shandong First Medical University
2020-2024
Academy of Medical Sciences
2020-2021
Taian City Central Hospital
2021
China Agricultural University
2014-2020
Taishan Medical University
2018
Tunghai University
2013
The University of Texas at Austin
1990-1998
Southeast University
1992
Institute of Physics
1987-1990
Chinese Academy of Sciences
1988
The nine-membered ring-bearing bicyclo[5.2.2]tetrahydrooxonines frameworks have enantioselectively been constructed via a tandem [3 + 2] cycloaddition/Cope rearrangement reaction of vinylethylene carbonates (VECs) with coumalates or pyrones. Under mild conditions, palladium-catalyzed asymmetric various substituted VECs and pyrones proceeds smoothly to produce the corresponding medium-sized heterocyclic compounds in high yields very enantioselectivities. Moreover, on gram scale further...
Abstract A formal [5+3] cycloaddition of zwitterionic allylpalladium intermediates with 1,3‐dipoles is developed, providing N,O‐containing eight‐membered heterocyclic compounds in high yields. Catalytically generated situ from vinylethylene carbonates or vinyloxiranes acted as dipolarophile. magnified image
An enantioselective synthesis of pharmaceutically important spirobarbiturates has been achieved via spirocyclic chiral phosphine-catalyzed asymmetric [4 + 2] annulation barbiturate-derived alkenes with allenoates. With the use this tool, various spirobarbiturate-cyclohexenes are obtained in good to excellent yields diastereo- and enantioselectivities. A wide range α-substituted allenoates were tolerated.
With the use of a commercially available chiral phosphine as catalyst, first catalytic enantioselective [4 + 3] annulation allenoates with C,N-cyclic azomethine imines is developed. The reaction works efficiently under mild conditions to afford seven-membered ring-fused quinazoline-based tricyclic heterocycles in high yields good excellent diastereo- and enantioselectivities.
Phosphine-catalyzed [2 + 4] annulation of allenoates with thiazolone-derived alkenes has been achieved under mild conditions, giving biologically important 6,7-dihydro-5H-pyrano[2,3-d]thiazole derivatives in high to excellent yields. With the use Kwon's phosphine as chiral catalyst, optically active products were obtained good yields enantioselectivities.
A palladium-catalyzed enantioselective [4 + 2] cycloaddition reaction of vinyl benzoxazinones with sulfamate-derived cyclic imines is described, affording the tetrahydroquinazolines bearing several functional rings in high yields (up to 99% yield) good excellent diastereoselectivities and enantioselectivities 96% ee). This represents first Pd-catalyzed asymmetric decarboxylative imines.
Palladium-catalyzed [5 + 2] cycloaddition of 2-aryl-2-vinyloxiranes with sulfamate-derived cyclic imines is described. The zwitterionic allylpalladium intermediates act as five-membered synthon to react furnish cycloaddition, giving 1,3-oxazepine derivatives in moderate excellent yields regioselectivities.
We have developed a process for growing as-deposited Y1Ba2Cu3O7−x (YBCO) thin films on R-plane sapphire substrates with an intermediate layer of epitaxial MgO. The orientation the layers has YBCO (001) parallel to MgO (100) which is substrate normal. These are superconducting by 88.5 K and exhibit Jc=1×106 A/cm2 at 77 2.5×107 4.2 K. may be grown temperatures as low 370 °C very stable in air. Little or no diffusion occurs between two measured Auger profiling.
Abstract Enantioselective synthesis of chiral quinazoline‐based heterocycles is achieved through a phosphine‐catalyzed [3+3] annulation reaction 1,3‐dipoles with Morita−Baylis−Hillman carbonates. The proceeds smoothly under mild conditions to give various heterocyclic compounds in high yields excellent diastereoselectivities and enantioselectivities. Further diverse elaborations the products work well produce novel tetrahydroquinazoline derivatives. magnified image
The Cu(I)-catalyzed highly enantioselective [3 + 3] cycloaddition between two different 1,3-dipoles, phthalazinium dicyanomethanides and iminoester-derived azomethine ylides, has been achieved under mild reaction conditions, providing novel chiral heterocyclic compounds, 2,3,4,11b-tetrahydro-1H-pyrazino[2,1-a]phthalazine derivatives, in high yields with excellent diastereo- enantioselectivies (up to 99% yield, ee, >20:1 dr).
A bifunctional phosphine-catalyzed highly enantioselective [2+4] cycloaddition of α-substituted allenoates with (E)-1-benzyl-4-olefinicpyrrolidine-2,3-diones has been achieved, giving pyrrolidin-2-one fused dihydropyran derivatives in moderate to good yields excellent enantioselectivities (up 98% ee). This reaction provides a useful catalytic asymmetric access structural motifs.
The first phosphine-catalyzed [5+1] annulation of enones with<italic>N</italic>-sulfonylimines works efficiently to give tetrahydropyridines.
The Sc(OTf)3-catalyzed diastereoselective [3 + 3] cycloaddition of phthalazinium dicyanomethanides with cyclopropane 1,1-diesters proceeded smoothly under mild reaction conditions, affording a variety 3,4-dihydro-1H-pyrido[2,1-a]phthalazine derivatives in up to 99% yields excellent diastereoselectivities.
Phosphine-catalyzed [4+1] annulation of 2-tosylaminochalcones with allenoates has been achieved, giving <italic>trans</italic>-2,3-disubstitued indolines as major diastereoisomers in moderate to good yields.
A BF
In this paper, a phosphine-catalyzed [8 + 2]-annulation of heptafulvene with allenoates has been achieved under mild conditions, giving functionalized bicyclo[5.3.0]decane derivatives in moderate to excellent yields. Using chiral phosphine as the catalyst, optically active products were obtained high yields enantioselectivities.
The phosphine-catalyzed tandem annulation reaction of Morita–Baylis–Hillman (MBH) alcohols with azomethine imines has been achieved for the synthesis biologically important (epoxymethano)-pyrazolo[5,1-b]quinazoline derivatives. A variety MBH and were well-tolerated under mild conditions, providing novel 3D heterocyclic compounds in high yields excellent diastereoselectivities. It is first time direct activation unmodified acting as new oxa-synthons achieved.
We have developed a low temperature magnetic force microscope capable of operation down to 6 K in vacuum by using piezoresistive cantilevers. use the non-contact frequency modulation technique detect gradient between an iron-coated tip and sample. demonstrate this new instrument obtaining images domains VHS tape at room temperature, 77 K. This is ideally suited for characterization thin films high superconductors.
A multifunctional chiral phosphine-catalyzed enantioselective [3+2] annulation of Morita-Baylis-Hillman carbonates with cyclopentenones provides a direct approach to access functional 4-oxo-1,3a,4,5,6,6a-hexahydropentalene compounds. Moderate good yields and excellent enantioselectivities (>90% ee) were obtained for series substrates under mild reaction conditions.
We herein designed and synthesized allenyl benzoxazinones of a novel type, which were then involved in Pd-catalyzed asymmetric cascade intramolecular cyclization/intermolecular Michael addition reaction with 1-azadienes. A broad range chiral C2-functionalized quinoline derivatives afforded moderate to good yields (up 93%) high enantioselectivities 93% ee) this reaction.
Pesticide stress on plants is receiving increased scrutiny due to its effect plant secondary metabolism and nutritional quality. Tannic acid (TA) a natural polyphenolic compound showing excellent antioxidant properties involved in alleviating stress. The present study thoroughly investigated the effects mechanism of exogenous TA relieving imidacloprid (IMI) tea plants. Our research found that TA(10 mg/L) activated defense system, enhanced ability, reduced accumulation ROS membrane...