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1.
Experimental Mechanics - Nanoelectromechanical (NEMS) systems fabricated using atomically thin materials have low mass and high stiffness and are thus ideal candidates for force and mass sensing...  相似文献   
2.
An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO4)3] and alumina sulfuric acid (Al2O3-SO3H) as heterogeneous catalysts was developed.  相似文献   
3.
A series of three-component reactions has been carried out using HClO4-SiO2 as a versatile heterogeneous catalyst. A series of new and novel N-protected 1-aminoalkyl-2-naphthol derivatives have been prepared under thermal solvent-free reaction conditions. In all cases, the reaction conditions were very simple and high-yielding.  相似文献   
4.
Herein we report, a rhodium-catalyzed Fujiwara-Moritani-type reaction of unactivated terminal alkenes and benzoic acid derivatives bearing electron donating residues under mild conditions. The acid functionality acts as a traceless directing group delivering products alkenylated in meta-position to the electron donating substituent in contrast to the usually obtained ortho- and para-substitution in Friedel-Crafts-type reactions. Remarkably, the new C−C bond is formed to the C2 of the terminal olefin, in contrast to similar reported transformations. Initially formed mixtures of exo- and endo-double bond isomers can be efficiently isomerized to the more stable endo-products.  相似文献   
5.
Russian Journal of Physical Chemistry A - The electronic and chemical properties of N-doped hybrid graphene and boron nitride armchair nanoribbons (N-doped a-GBNNRs) in comparison with graphene...  相似文献   
6.
Indole derivatives are an important class of heterocycle found in a large number of natural products and synthetic pharmaceuticals. Given the low cost and easy availability of N-propargyl anilines, synthesis of indole cores from these versatile structural motifs has attracted a lot of attention in the past decade. In this review, we summarize the most representative and interesting reports on this rapidly advancing area, with special emphasis on mechanistic aspects of the reactions.  相似文献   
7.
Herein, we describe a green procedure for the one-pot preparation of 1,8-dioxo-octahydroxanthene derivatives by condensation of dimedone and substituted benzaldehydes in the presence of FeCl 3 -SiO 2 as an efficient and heterogeneous catalyst under microwave irradiation and thermal conditions. This method has the advantages of high yields, cleaner reactions, efficient and cost-effective method, simple methodology, short reaction times, easy workup, and greener conditions.  相似文献   
8.
An efficient palladium catalyst was synthesized using nicotine, benzyl chloride and palladium chloride. The structure of this catalyst was characterized and it was then used for the synthesis of diaryl sufides. A variety of diaryl thioethers were synthesized under relatively mild reaction conditions. This protocol avoids foul‐smelling thiols via cross‐coupling of aryl halides with potassium thiocyanate and all substrates give the corresponding products in good to excellent yields in the presence of low amounts of the catalyst. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
9.

Abstract  

A simple, efficient, and green method for synthesis of 2,4,6-triarylpyridines by one-pot three-component reaction of acetophenones, aryl aldehydes, and ammonium acetate using 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogen sulfate [HO3S(CH2)4MIM][HSO4], a Br?nsted-acidic ionic liquid, as an effective and reusable catalyst under solvent-free conditions is described. This method has several advantages, for example simple procedure with an easy work-up, shorter reaction times, and high yields.  相似文献   
10.
Composite of conductive polyaniline-isobutylated urea formaldehyde have been prepared by chemical oxidative emulsion polymerization of aniline in the presence of isobutylated urea formaldehyde resin (BUFR) in toluene-water solvents at room temperature. The mass loading of polyaniline was controlled by varying the BUFR/aniline charging ratio as well as oxidant (ammonium persulfate)/aniline molar ratio. Some factors capable of affecting the yield and conductivity of composite, such as amount of the oxidant, type of the dispersants (span-80 and span-20), and amount of resin and organic acid (para-toluene sulfonic acid) were investigated. The prepared composites were characterized by FTIR spectroscopy and scanning electron microscopy (SEM).  相似文献   
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