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1.
Zhao W  Carreira EM 《Organic letters》2003,5(22):4153-4154
[reaction: see text]. Photochromic pyrans, including [3H]naphtho[2,1-b]pyrans, [2H]naphtho[1,2-b]pyrans, indeno-fused naphtho[1,2-b]pyrans, and heteroannulated pyrans, were synthesized in excellent yields through a facile one-pot procedure by reaction of propargyl alcohol and naphthol or phenol derivatives in the presence of 5 mol % PPTS and 2 equiv of (MeO)3CH. Symmetrical and nonsymmetrical bispyrans can also be prepared using the protocol.  相似文献   

2.
We report a novel one-pot two-step synthesis of a variety of S-alkyl thiocarbamates. This method offers a two-directional approach making use of trichloroacetyl chloride, requires no complex starting material, incorporates a variety of substituents, and proceeds in high yields.  相似文献   

3.
5-Substituted and 5,5-disubstituted hydantoins are synthesised from the corresponding aldehydes or ketones, using a one-pot, gallium(III) triflate-catalysed procedure that is compatible with a range of substrates and solvents.  相似文献   

4.
Ando M  Wada T  Sato N 《Organic letters》2006,8(17):3805-3808
[reaction: see text] A novel one-pot synthesis of N-difluoromethyl-2-pyridones is described. N-(Pyridin-2-yl)acetamide derivatives were excellent precursors for the preparation of N-difluoromethyl-2-pyridone derivatives. Difluoromethylation of 2-acetaminopyridine derivatives was achieved with sodium chlorodifluoroacetate as a difluorocarbene source in the presence of a catalytic amount of 18-crown-6. Subsequent in situ hydrolysis of resultant 1,2-dihydro-2-acetimino-1-difluoromethylpyridines proceeded under mild acidic conditions to afford the corresponding N-difluoromethyl-2-pyridones in moderate to good yields.  相似文献   

5.
A series of arene and heteroarene sulfonamides were prepared in one vessel from aryl and heteroaryl bromides via conversion into the corresponding Grignard reagents using either magnesium or isopropylmagnesium chloride and subsequent reaction with sulfur dioxide, sulfuryl chloride, and an amine.  相似文献   

6.
A polycyclic aromatic compound, anthracene, was covalently connected through a methylene bridge via Friedel-Crafts alkylation reaction. Thus, a highly fluorescent anthracene polymer (PMAn) linked by a methylene unit was prepared in one step to produce a conjugated-nonconjugated spacer-type polymer through its reaction with chloromethyl methyl ether (CME) and FeCl3 at 0 °C. The resultant polymer was soluble in organic solvents and showed significantly higher fluorescence (quantum yield = 0.80) compared to monomeric anthracene, 9-methylanthracene, in chloroform solution. Fluorescent thin films of PMAn as solid media were prepared with high film uniformity. The emission of the film was extinguished when the film was exposed to a UV source, due to the photodimerization of anthracene unit. A fluorescent gap electrode pattern was formed on the polymer film-forming average step depth of 8 nm and 14 nm, after 30 and 60 min irradiation with a UV light, respectively. The photo patternable fluorescent polymer afforded a convenient method of image formation and patterning.  相似文献   

7.
This communication reports facile one pot synthesis of amoxicillin and sodium salt of amoxicillin stabilized gold nanoparticles (Au-NPs). Primarily the cyclic thioether linkage i.e. the thiozolidine ring of amoxicillin is utilized for sequestering Au(III). Fluorescence quenching of these clusters makes it an efficient protocol for sensing Cu(2+) at nano scale levels.  相似文献   

8.
A one-pot approach to the synthesis of novel glycosylidene-based quinolines is described. The reaction involves a Lewis acid catalyzed Povarov addition followed by oxidation of the resulting spiroanellated tetrahydroquinoline intermediates to yield the open-ring glycosylidene-derived quinoline.  相似文献   

9.
Yolk-shell composites with an Fe(3)O(4)/silica hybrid shell and a polymer core are prepared via a facile one-pot and self-template process. Thicknesses of the inorganic shell and interior space of the composites are well controlled by tuning the ternary phase separations.  相似文献   

10.
A one-pot colloidal reaction strategy was developed to synthesize asymmetric magnetic composite particles (AMCPs) with high anisotropy and magnetic content. The asymmetricity was established by having two portions of the particle composed of both polystyrene and silica, among which the latter was conjugated with magnetite nanoparticles. Phase separation was found to be critical in developing the asymmetric structure between the inorganic and polymer components during miniemulsion polymerization and the sol-gel reaction. Morphological control of the magnetic composite particles was achieved in a straightforward fashion by adjusting the processing parameters. These asymmetric nanomaterials with superparamagnetic and amphiphilic properties will have significant potential in biomedical applications.  相似文献   

11.
12.
The reaction of phosphorus trichloride with 2,6-diisopropyl phenol in the presence of LiCl under reflux conditions for 24 h produces a mixture of (ArO)PCl2 and (ArO)2PCl (Ar = 2,6-iPr2C6H3). The hydrolysis of the aryloxy compounds in acetone/H2O results in the formation of two novel phosphonate ester derivatives [(ArO)P(O)(OH)(CMe2OH)] (1) and [(ArO)2P(O)(CMe2OH)] (2), respectively in a moderate yield. The title compounds have presumably formed via acetone insertion to the P-H bonds of (ArO)P(O)(H)(OH) and (ArO)2P(O)(H), respectively, in the presence of HCl produced during the hydrolysis. Compounds 1 and 2 have been characterized by elemental analysis, and ESI-mass, Infrared and NMR spectroscopic techniques. Further, solid state structures of 1 and 2 have been established by single crystals X-ray diffraction studies.  相似文献   

13.
In this work, we describe the one-pot synthesis of PEGylated mesoporous silica nanoparticles (MSNs) with uniform shape, tunable sizes, and narrow size distributions. The size of these nanoparticles can be controlled from 49 nm to 98 nm by simply varying the concentration oftriethanolamine during the base- catalyzed sol-gel reaction. Particles were characterized by transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectrometry, thermogravimetric analysis, and nitrogen adsorption-desorption measurements. These PEGylated MSNs exhibited excellent long-term stability in biological media, which ensures their potential applications in drug delivery.  相似文献   

14.
[reaction: see text] Alkyl/aryl amidoximes, prepared from the corresponding nitriles and N-alkylhydroxylamines, have readily undergone consecutive Michael additions to electron-deficient alkynes and provided highly substituted 1,2,4-oxadiazolines in good yields in homogeneous aqueous solution.  相似文献   

15.
This communication reports facile synthesis of copper sulfide-metal chalcogenide heteronanostructures. This one-pot two-step approach works because both seeds and precursors can be grown controllably in the same reaction vessel without intermediate seed purification, yielding easy handling, and high synthetic reproducibility.  相似文献   

16.
The efficient synthesis of perfluoroalkyl-substituted fluorenes directly from indenones, malononitrile and methyl perfluoroalk-2-ynoates via a one-pot two-step three-component cascade process is reported. Up to 12 examples of indenones with various substituents were converted into their corresponding functionalized fluorene derivatives in good to excellent yields.  相似文献   

17.
Chemistry of Heterocyclic Compounds - A facile one-pot synthesis of N-fused 1,2,4-triazoles from heterocyclic hydrazines and aldehydes is reported. The reaction is efficiently promoted by manganese...  相似文献   

18.
A method for the direct one-pot synthesis of amine-stabilized gold nanoparticles using 3-(trimethoxysilylpropyl)diethylenetriamine (TMSP dien) is described. The amine groups of this bifunctional molecule act as a stabilizer for gold nanoparticles as they form by reduction of HAuCl4. Highly stable gold nanoparticles with sizes tunable between 8 and 20 nm can be readily obtained. This method is quite simple to implement and environmentally benign as there is no need to add an external reducing reagent. The incorporated siloxy functionality was subsequently used to form a silica shell around the gold particle.  相似文献   

19.
A one-pot reaction sequence of sequential phosphine-promoted tandem annulations of aryl trifluoromethyl ketones and MBH (Morita-Baylis-Hillman) carbonates and DBU-mediated aminolysis was developed. This method provides a step-economical approach to trifluoromethylated dienamides with diverse structural complexity from readily available starting materials in moderate yields.  相似文献   

20.
Doping and functionalization could significantly assist in the improvement of the electrochemical properties of graphene derivatives. Herein, we report a one-pot synthesis of fluorinated graphene oxide (FGO) from graphite. The surface morphology, functionalities and composition of the resulting FGO have been studied using various surface characterization techniques, revealing that layer-structured nanosheets with ~ 1.0 at.% F were formed. The carbon bound F exhibited semi-ionic bonding characteristic and significantly increased the capacitance of FGO compared to GO. Further, the FGO has been employed for the simultaneous detection of heavy metal ions Cd2 +, Pb2 +, Cu2 + and Hg2 + using square wave anodic stripping voltammetry; and a substantial improvement in the electrochemical sensing performance is achieved in comparison with GO.  相似文献   

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