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931.
Thiomethylation of resorcin[4]arene using N,N-diisopropyl-2-aminoethanethiol hydrochloride and formaldehyde [1:4:4 molar ratio] carried out in methanol/acetic acid [1:1 v/v] at 60 °C produced monofunctionalized product 3 in 68% yield. The introduced substituent was intramolecularly self-included into the cavity. This self-inclusion reduced the reactivity of the aromatic rings and inhibited further functionalization.  相似文献   
932.
α-Zirconium phosphate was chemically modified with 1,2-bis(dimethylchlorosilyl)ethane to graft organic chain, and then it was used as host material for inorganic nanosheet-polyaniline hybrid. The grafted α-zirconium phosphate was exfoliated in an acetonitrile solution with tetrabutylammonium salt and aniline. The electrodeposition in the presence of aniline was performed, and then it resulted in a formation of higher-order structure in which phosphate nanosheet was propped up by 1,2-bis(dimethylchlorosilyl)ethane with intrusion of polyaniline into the nanospace. The gravimetric capacitance of the α-zirconium phosphate without grafts and polyaniline hybrid film was around 194 F/g with the base on the amount of polyaniline mass. On the other hand, the α-zirconium phosphate nanosheet with grafts and polyaniline hybrid film provided larger capacitance of around 350 F/g in maximum. The nanospace formed by grafted phosphate nanosheet with 1,2-bis(dimethylchlorosilyl)ethane molecules gives increased amounts of polyaniline included and diffusion paths for ions.  相似文献   
933.
A convergent and enantioselective route to the hNK-1 receptor antagonist (1) is described, which sets all six stereogenic centers with high diastereoselectivity and delivers 1 in only 11 steps and 23% overall yield. The process was enabled by the development of the enantioselective enzymatic reduction of 3-functionalized cyclopentenones and stereospecific Pd-catalyzed etherification coupling of fragments 6 and 7.  相似文献   
934.
The design space of the granulation process of mefenamic acid tablets, based on Box and Behnken design datasets, was described by a response surface method incorporating multivariate spline interpolation. The reliability of the optimal solutions and the acceptance ranges were evaluated by a bootstrap (BS) resampling technique. The distribution of the BS optimal solutions was almost symmetrical; however, several solutions, which were quite different from the original solution, were mixed. The reason for this problem was considered to be the mixing of the global and the local optima. Therefore, we applied self-organizing map (SOM) clustering for dividing data into several clusters and identified the cluster containing the global optima. The accuracy and reproducibility of the optimal solution in the cluster containing the optimal solution were quantitatively evaluated. In addition, the response surfaces modeled from all the BS datasets contained in the cluster were plotted into the same coordinates with the original response surface. The plots of BS optimal solutions were distributed around the original solution. Moreover, the average of all the BS response surfaces sufficiently corresponded with the original response surface. The conservative limits of the 95% confidence intervals of the acceptance ranges in three response variables could be calculated using the standard deviations of the BS response surfaces. Consequently, it was considered that a novel evaluation method based on BS resampling and SOM could be used for quantitatively evaluating the precision of the nonlinear response surface model.  相似文献   
935.
Copper-catalysed oxidative hydroxylation of arylboronic acids was accomplished in water containing an amphiphilic surfactant, providing facile access to phenol derivatives.  相似文献   
936.
The relative reactivities of Zn, Al, and Sm carbenoids in the chemoselective carbene insertion reaction of heavier group 14 hydrides were studied. By variation of the reaction protocols using Sm carbenoids, insertion reaction can favour the Ge-H bonds to give Ge-alkylated derivatives in good to high yield.  相似文献   
937.
A facile, efficient, and general synthetic method for 3,4-dihalofurans has been developed via the electrophilic iodocyclization of various 4-hydroxy-2-but-2-yn-1-ones. The use of MeOH as a solvent is crucial for the efficient chemoselective synthesis of the corresponding 3,4-dihalofurans.  相似文献   
938.
939.
A facile, efficient, and general synthetic method for a wide range of 2,3-diiodinated 1,4-dihydrothiophenes and naphthalenes has been developed via the electrophilic iodocyclization of various aryl propargyl alcohols. The resulting product 2p can be used for the synthesis of a rubrene intermediate.  相似文献   
940.
Linear and branched Fe(tpy)(2) complex oligomer wires were quantitatively formed on hydrogen-terminated silicon wafers by means of hydrosilylation of ethynylterpyridine and following stepwise coordination reactions, and the redox property of surface-attached species and its photosensitivity can be controlled by the doping density of the silicon wafers.  相似文献   
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