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41.
Catalytic CO2 reduction to fuels and chemicals is a major pursuit in reducing greenhouse gas emissions. One approach utilizes the reverse water‐gas shift reaction, followed by Fischer–Tropsch synthesis, and iron is a well‐known candidate for this process. Some attempts have been made to modify and improve its reactivity, but resulted in limited success. Now, using ruthenium–iron oxide colloidal heterodimers, close contact between the two phases promotes the reduction of iron oxide via a proximal hydrogen spillover effect, leading to the formation of ruthenium–iron core–shell structures active for the reaction at significantly lower temperatures than in bare iron catalysts. Furthermore, by engineering the iron oxide shell thickness, a fourfold increase in hydrocarbon yield is achieved compared to the heterodimers. This work shows how rational design of colloidal heterostructures can result in materials with significantly improved catalytic performance in CO2 conversion processes.  相似文献   
42.
Novel efficient chiral tetraoxacalix[2]arene[2]triazine-based organocatalysts have been designed and synthesized from the reaction of tetraoxacalix[2]arene[2]triazine with R/S-phenylethylamine or R/S-1-naphthylethylamine for the Aldol reaction of acetone with aromatic aldehydes to furnish the Aldol adducts in 71–92% yields with excellent enantioselectivities (78–99%).  相似文献   
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1,3-Disubstituted-2,3-dihydro-1H-naphth[1,2-e][1,3]oxazines were prepared through the ring-closure reactions of the aminobenzylnaphthols with substituted aryl- and heteroarylaldehydes.  相似文献   
45.
An efficient synthesis of 2‐arylamino‐2‐imidazolines from dimethyl N‐aryldithioimidocarbonates and ethylenediamine on solid support under microwave irradiation has been developed. The reaction time has been reduced from hours to minutes with improved yields as compared to conventional heating. Their piperidin‐4‐ylmethyl and morpholin‐4‐ylmethyl derivatives were synthesized by treatment with formaldehyde and piperidine or morpholine. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:142–222, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20081  相似文献   
46.
Journal of Fluorescence - A propylimidazole functionalized coumarin derivative (IPC) was fabricated for the first time and applied as a dual responsive fluorescent chemoprobe for sensitive and...  相似文献   
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Reaction of trichloronitromethane with secondary amine leads to the formation of corresponding carcinogeneous N-nitrosamines under mild conditions.  相似文献   
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Abstract

Eleven new alkyl and aryl amino quinones were synthesized from quinones (2,3-dibromo-1,4-naphthoquinone 1, 2-bromo-1,4-naphthoquinone 2, p-benzoquinone 3 or 2,6-dichloro-1,4-benzoquinone 8) with primary amines. The structures of all compounds were characterized by spectroscopic technics and elemental analysis. The structure of 2-((6,6-Dimethylbicyclo[3.1.1]heptan-2-yl)methylamino)-3-bromonaphthalene-1,4-dione (5a) was established by single crystal diffraction. 2-(2-(Ethylthio)ethylamino)naphthalene-1,4-dione (6b) was found to have noteworthy antiproliferative effect against MDA-MB-231 cells.  相似文献   
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