نتایج جستجو برای: arenes
تعداد نتایج: 1476 فیلتر نتایج به سال:
One-dimensional (1D) channel structures, have spaces, entrances, and exits of specific sizes, therefore guest molecules can travel through the from entrance to exit. Such 1D structures are ideal platforms for transporting molecules. In this mini-review, we will discuss preparation molecular-scale continuous channels pillar[n]arenes by using non-covalent interactions covalent bonding. Because th...
The solvent free route for the synthesis of diaryl sulfoxides from arenes and thionyl chloride in the presence of Lewis acids such as aluminum chloride and ferric chloride on silica gel are described.
The 1-N-benzyl-5-iodo(or bromo)uracil undergoes Pd-catalyzed [Pd2(dba)3] direct arylation with benzene and other simple arenes in the presence of TBAF in DMF without the necessity of adding any ligands or additives to give 5-arylated uracil analogues. The TBAF-promoted coupling also occurs efficiently with electron rich heteroarenes at 100 °C (1 h) even with only small excess of heteroarenes. T...
A catalyst for the intramolecular direct arylation of a broad range of simple and heterocyclic arenes with aryl iodides, bromides, and chlorides has been developed. These reactions occur in excellent yield and are highly selective. Studies with aryl iodides substrates revealed that catalyst poisoning occurs due to the accumulation of iodide in the reaction media. This can be overcome by the add...
A series of products based on tert-butylcalix[4]arene have been synthesized by anionic polymerization of ethylene oxide. The resulting products are amphiphilic octopus-shaped macromolecules, consisting of a hydrophobic calix[4]arene core and four arms of hydrophilic poly(ethylene oxide) chains. In aqueous solutions the polyoxyethylated tert-butylcalix[4]arenes were found to self-associate above...
Recently, the surprising result that ab initio calculations on benzene and other planar arenes at correlated MP2, MP3, configuration interaction with singles and doubles (CISD), and coupled cluster with singles and doubles levels of theory using standard Pople's basis sets yield nonplanar minima has been reported. The planar optimized structures turn out to be transition states presenting one o...
A transition-metal-free direct oxidative trifluoromethylation of unsymmetrical biaryls has been achieved by the simple combination of trifluoromethanesulfinate and phenyliodine bis(trifluoroacetate). The trifluoromethylation is selectively observed in the electron-rich arenes.
Using the phospholane-phosphite ligand, BOBPHOS, almost perfect regioselectivities and high enantioselectivities (up to 92% ee) are observed in Rh catalysed enantioselective hydroformylation of vinyl arenes. This can be achieved under solvent-free conditions.
Several arenes possessing a cyclopropyl substituent were subjected to enzymatic oxidation with toluene dioxygenase. The absolute configuration of metabolites was established by chemical means. 2005 Elsevier Ltd. All rights reserved.
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