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Summary.  N,N-Dimethylhydrazones of ketones and aldehydes undergo facile cleavage to the corresponding carbonyl compounds upon exposure to microwaves in water containing a catalytic amount of PdCl2–SnCl2 in high yields. Corresponding authors. E-mail: rahman@umz.ac.ir Received December 27, 2001. Accepted (revised) February 6, 2002  相似文献   
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Aliphatic and aromatic 1,3‐dithiane are oxidized to the corresponding carbonyl compounds in good yields under mild conditions by N,N′‐diiodo‐N,N′‐1,2‐ethanediyl‐bis(p‐toluenesulphonamide) [NIBTS] and silver nitrate.  相似文献   
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Poly [N‐bromo‐benzene‐1,3‐disulfonylamide] [ PBBS ] is a novel and efficient reagent for the conversion of oximes and semicarbazones under solid state to their corresponding carbonyl compounds in high yields.  相似文献   
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Journal of Thermal Analysis and Calorimetry - Due to limited energy supply sources and environmental issues, the use of renewable energy to replace fossil fuels and reduce pollution has increased....  相似文献   
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Journal of Thermal Analysis and Calorimetry - Nowadays, with increasing energy consumption, global warming, and many problems caused by weather conditions, the tendency to use novel methods of...  相似文献   
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Electron-rich aromatic compounds react with formaldehyde and a secondary amine under solvent-free condition, in the presence of acidic alumina in a commercial microwave oven or at room temperature to produce aminomethylated products in good to excellent yields.  相似文献   
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Several new clip-shaped molecules, with different degrees of steric hindrance around their cavities as well as more rigidity on their glycoluril scaffold, have been synthesized and the molecular geometry of their most stable structures has been investigated and optimized with density functional theory (DFT) at the B3LYP level of theory using 6-311G basis set. The affinity of these molecular clips for some dihydroxybenzene derivatives (guests) has been computationally and experimentally studied. The clips having dimethyl-substituted aromatic side walls, showed the best interaction energies towards the mentioned guests. Also, the computational results revealed that the more electron-deficient guest interacts more strongly with the clips (hosts).  相似文献   
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Journal of Thermal Analysis and Calorimetry - The increasing growth of helium consumption in industries and the limited resources of this element are the challenges that industries will face in the...  相似文献   
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Journal of Thermal Analysis and Calorimetry - This work presents numerical simulation of two-dimensional thermogravitational energy transport in a chamber filled with copper–water ( $${\hbox...  相似文献   
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