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41.
Leslie M. Werbel Edward F. Elslager Vera P. Chu 《Journal of heterocyclic chemistry》1973,10(4):631-635
3,4-Dichlorophenylisothioeyanate ( 10 ) was allowed to react with 2-methy1-2-thiopseudourea to give methyl 4-(3,4-dichlorophenyl)(dithioaltophanimidate ( 11 ) (41%), which upon treatment with hydrazine afforded 3-amino-5-(3,4-dichloroanilino)-s-triazole ( 12 ) (54-91%). Ring-closure with ethyl acetoacetale in acetic acid afforded 2-(3,4-dichloroanilino)-5-methyl-s-triazolo[ 1,5-α ]-pyrimidin-7-ol ( 13 ) (81%). Chlorination with phosphorus oxychloride gave 7-chloro-2-(3,4-dichloroanilino)-5-methyl-s-triazolo[1,5-α ]pyrimidine ( 14 ) (98%), which was condensed with various amines to yield the desired 2-(3,4-diehloroanilino)-7-¶[(dialkylamino)alkyl]arnino¶-5-methyl-s-triazolo[ 1,5-α]pyrimidines ( 6 a-d). The structures of the s-triazolo[ 1,5-α ]pyrimidines were based on nmr spectroscopy and ring stability considerations. Several of the amino-s-triazolo[ 1,5-α ]pyrimidines possessed antimalarial activity against P. berghei in mice. 相似文献
42.
Copper ion-exchanged ZSM5 zeolites have been prepared with different cooper loadings from under- to over-exchanged levels. The adsorptions of N2O and CO at 303 K have been studied using calorimetric method and infrared spectroscopy. The samples were additionally characterised by ammonia adsorption at 423 K. The active sites for both N2O and CO are Cu(I) ions, which were formed as a result of pre-treatment in vacuum at 673 K.
Room temperature adsorption of nitrous oxide at low equilibrium pressures (up to 66.7 Pa) resulted in small amounts of chemisorbed N2O (<0.2 molecule per one Cu ion). Differential heats of N2O adsorption between 80 and 30 kJ/mol were obtained. Differential heats of CO adsorption between 140 and 40 kJ/mol were obtained. The obtained amounts of chemisorbed species in the investigated systems and the values of differential heats of both nitrous oxide and carbon monoxide demonstrate the dependence on the copper content. 相似文献
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Thionyl chloride-pyridine mediated rearrangement of cylohexadienyl alcohols (2) and (8) has provided hyposantonin (3) and tetrahydronaphthalene (9), respectively, which in turn have served as potential intermediates for the synthesis of optically active and racemic occidol (6), respectively. 相似文献
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Özlem Usluer Christian Kästner Mamatimin Abbas Christoph Ulbricht Vera Cimrova Andreas Wild Eckhard Birckner Nalan Tekin Niyazi Serdar Sariciftci Harald Hoppe Silke Rathgeber Daniel A. M. Egbe 《Journal of polymer science. Part A, Polymer chemistry》2012,50(16):3425-3436
This article reports on the synthesis, characterization, and properties of various anthracene‐containing poly (p‐phenylene‐ethynylene)‐alt‐poly(p‐phenylene‐vinylene) (PPE‐PPV) polymers (AnE‐PVs) bearing statistical distributions of various side chains. Primarily, the ratio of linear octyloxy and branched 2‐ethylhexyloxy side chains at the poly(p‐phenylene vinylene) (PPV) parts was varied, leading to the polymers stat, stat1, and stat2. Furthermore, polymers also containing asymmetric substituted PPV and poly(p‐phenylene ethynylene) units (bearing methoxy and 2‐ethylhexyloxy side chains) were prepared yielding stat3, stat4, and stat5. These materials exhibit a broad variation in their photovoltaic properties. It is once more shown that side chains and their distribution can crucially affect the photovoltaic device performance. The introduction of units with asymmetric substitution into these systems seems to be harmful for their utilization in photovoltaic applications. Organic field‐effect transistors were fabricated to investigate hole mobilities in these new materials. Large variance was observed, falling in the range of almost two orders of magnitude, indicating rather different π–π stacking behavior of the polymer backbones owing to side‐chain modifications. Moreover, a selection of the new polymeric systems was investigated regarding their potential for light‐emitting diode (LED) applications. Polymer LEDs using the polymers AnE‐PVstat, ‐stat3, ‐stat4, and ‐stat5, as the active layer showed turn‐on voltage of ~2 V and exhibited red light emission. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Vera I. Filyakova Nadezhda S. Boltacheva Marina G. Pervova Valery N. Charushin 《Mendeleev Communications》2021,31(3):388-389
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50.
Potentiostatic (galvanostatic) electrolysis of NH4SCN in an undivided cell under mild conditions (25 °C, Pt anode, MeCN) was employed to perform the anodic thiocyanation of nitrogen-containing heterocycles with yields up to 95%. The regularities of the process are discussed, which show that it can be considered as electroinduced nucleophilic aromatic substitution of hydrogen. 相似文献