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Abstract

The synthetic potential of 2,3,4,5-tetrahydrobenzo[b] [1,5]thiazepine-1,1,4-trione-2-carbohydrazide (5) which resulted from ethyl-4-oxo-2,3,4,5-tetrahydrobenzo[b] [1,5]thiazepine-2-carboxylate (3), on its oxidation with H2O2/AcOH followed by treatment with NH2NH2.H2O, was exploited to provide an access to 2-triazolo, 2-oxadiazolo, and 2-pyrazolo substituted derivatives of 1,5-benzothiazepin-4-oxo-1,1-dioxides (6–10), respectively.  相似文献   
2.
Bromomethyl (E)-2-phenylethenyl and bromomethyl (Z)-1-bromo-2-phenylethenyl sulfones undergo condensation with enolates generated from malononitrile, dimethyl malonate, methyl and ethyl acetoacetate using NaH in THF to give tetrahydrothiophene S,S-dioxides. Methyl (E)-1-bromo-2-phenylethenyl and methyl (E)-2-bromo-2-phenylethenyl sulfones react with sodium malononitrile to give 2-[2-(methylsulfonyl)-1-phenylethylidene]malononitrile. The bromomethyl-(E)-2-bromo-2-phenyl ethenyl sulfone reacts with sodium malononitrile to give 2-[2-(bromomethylsulfonyl)-1-phenylethylidene]malononitrile exclusively. Dedicated to Professor A. A. Potekhin’s memory. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 539–551, April, 2008.  相似文献   
3.
Cycloaddition reactions of 2,5-di-tert-butylthiophene S-oxide and 2,3,4,5-tetrakis(p-tolyl)thiophene S-oxide with alkenes are described. The reactivity of 2,5-di-tert-butylthiophene S-oxide as diene in Diels–Alder reactions is compared with 2,5-di-tert-butylthiophene S,S-dioxide. The thermal and photochemical SO extrusion reactions of the cycloadducts under formation of highly substitutedaromatic compounds are exemplified.  相似文献   
4.
将新型磷酸基光控保护基(2-重氮基-3-苯基-4H-磺酰基苯并噻喃,PPG)应用于氨基酸[甘氨酸(1a), L 丙氨酸(1b), L 苯丙氨酸(1c)和L-脯氨酸(1d)]的保护 光控脱保护反应。产物结构经1H NMR, 13C NMR和HR-FAB MS表征。研究了物料比r[n(PPG) : n(1a)],催化剂和反应温度对2a收率的影响。结果表明:在最佳反应条件[1a 0.1 mmol, r=1.25,于室温反应65 h]下,2a收率80%。FL监测光控脱保护反应表明:反应在15 min内完成。  相似文献   
5.
Bipolar blue light-emitting polyfluorenes(PFSO-Cz) containing electron-deficient dibenzothiophene-S,S-dioxide(SO) and electron-rich carbazole(Cz) unit were synthesized. All the polymers show a high thermal stability with the decomposition temperatures over 400℃ and higher photoluminescence quantum yields. The highest occupied molecular orbital energy levels(EHOMO's) slightly enhance and the lowest unoccupied molecular orbital energy levels(ELUMO's) gently depress with the increase of Cz content in the polymers. PL spectra of the polymers display remarkable red shift and broadening with the increase of solvent polarities, indicating significant intramolecular charge transfer(ICT) effect in the polymers. Electroluminescence(EL) spectra of the polymers exhibit a broadening tendency with increasing the content of Cz unit in the polymers. The superior device performances were obtained with the maximum luminous efficiency(LE­max) of 5.2 cd/A, the maximum external quantum efficiency(EQEmax) of 4.8% and the Internationale de l'Eclairage(CIE)(x,y) coordinates of (0.16, 0.17) for PFSO15-Cz10 based on the single-layer device of ITO/PEDOT:PSS/EL/CsF/Al. The results indicate that the efficient bipolar blue light-emitting polyfluorenes are also constructed by Suzuki copolymerization using the monomers in common use.  相似文献   
6.
以苯硫酚为起始原料,经脱水反应、碘代反应、Suzuki-Miyaura偶联反应和氧化反应制得4-酮基-3-苯基-4H-苯并噻喃-2-甲醛(4); 4经间氯过氧苯甲酸氧化后与对甲苯磺酰肼于室温反应制得2-甲苯磺酰腙-3-苯基-4H-磺酰基苯并噻喃(6); 6经Bamford-Stevens反应合成了一种新型磷酸基光控保护基--2-重氮基-3-苯基-4H-磺酰基苯并噻喃(7),其结构经1H NMR, 13C NMR和HR-MS表征。将7应用于磷酸基团的保护和光控脱保护反应中。结果表明:保护反应可在温和条件下顺利进行。紫外光谱法和荧光光谱法对光控脱保护反应的监测结果表明:光控脱保护反应迅速(≤15 min),被保护化合物脱保护收率高(≥95%)。  相似文献   
7.
Summary.  Various heteroaromatic N-oxides were efficiently deoxygenated to the corresponding bases under mild conditions using formamidinesulfinic acid (thiourea S,S-dioxide). Received March 24, 2000. Accepted April 18, 2000  相似文献   
8.
A series of trisbenzothieno[1,2:7,8:13,14]hexa‐peri‐hexabenzocoronenes were synthesized and characterized by a combination of NMR, 2D NMR, MALDI‐TOF MS, UV/Vis absorption spectroscopy, and 2D‐WAXS measurement. By structural modulation like decoration of electro‐donating alkoxyl chain, and conversion from an electron‐rich thiophene ring into an electron‐poor thiophene‐S,S‐dioxide moiety, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of the hexabenzocoronenes derivatives can be effectively tuned which is further verified by the DFT calculations and cyclic voltammetry.  相似文献   
9.
杨君维  王淑萌  丁军桥  王利祥 《应用化学》2014,31(10):1156-1163
将缺电子单元-S,S-二氧-二苯并噻吩(SO)以2,8位引入到聚螺芴(PSFs)的主链,通过Suzuki聚合得到一系列具有不同SO含量的共聚物PSF-28SO-3、PSF-28SO-5、PSF-28SO-7和PSF-28SO-10。 不同于3,7位连接,该系列2,8-位连接的共聚物既有来自于高分子主链的本征态(LE:local excited)发光,又有来自于从四烷氧基芴侧链到主链中SO单元的电荷转移(CT:charge transfer)发光,最终表现为近白光发射。 其中,PSF-28SO-10具有最优器件性能,发光效率为0.58 cd/A,色坐标为(0.25,0.36)。  相似文献   
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