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91.
Dmitrii Semenok Alexey Kletskov Evgenij Dikusar Vladimir Potkin Oleg Lukin 《Tetrahedron letters》2018,59(4):372-374
A library of 4′-chloro- and 4′-fluorosulfonyl-substituted chalcones was prepared via the aldol-type condensation reactions of 4-acetylbenzene-1-sulfonyl halides with various aromatic aldehydes, either in absolute ethanol or glacial acetic acid, in the presence of dry HCl. This represents the first examples of chalcone sulfonyl halides in which the phenone ring bears one of these functional groups. The reactivity of the chalcone sulfonyl halides were strongly dependent on the styrene ring substituents; sulfonyl chlorides reacted with most nucleophiles (e.g. amines, alcohols), while sulfonyl fluorides reacted only with charged nucleophiles (e.g. phenolates). 相似文献
92.
Chlorosulfonyl-containing naphthol azo compounds were prepared by reaction of the corresponding sulfonate-containing naphthol
azo dyes with thionyl chloride in the presence of a catalytic quantity of N,N-dimethylformamide and various solvents. The yields and reaction selectivity of chlorosulfonyl-containing naphthol azo compounds
were discussed according to the properties of solvents. It was demonstrated that high chemical selectivity and high yield
were achieved by using benzene, toluene or thionyl chloride as solvent. Additionally, on account of unstable properties of
sulfonyl chloride compounds in MS and 1H-NMR analyses, a new analytical method using stable sulfonamide is put forward to verify the chemical structures of the corresponding
sulfonyl chloride compounds indirectly.
__________
Translated from Journal of Dalian University of Technology, 2008, 48(1): 26–32 相似文献
93.
AlCl3-mediated tandem Friedel-Crafts reaction of vinylidenecyclopropanes with acyl chlorides produced the corresponding 1-[2-(2,2-diarylvinyl)-1-phenyl-3H-inden-5-yl]ethanone derivatives in moderate to good yields under mild conditions within short reaction time. 相似文献
94.
季铵盐型离子液体中全氟烷基磺酰亚胺盐催化的芳烃硝化反应 总被引:1,自引:0,他引:1
全氟烷基磺酰亚胺盐与季铵型离子液体(Cu(N(C4F9SO2)2)2/[N4446][NTf2] 或 In(NTf2)3/[N4446][NTf2])组成的新催化体系,可以很好的催化芳香族化合物的硝化反应。以氯苯的硝化为例,用硝酸和醋酸酐混合物为硝化试剂,在2mol%的Cu(N(C4F9SO2)2)2或In(NTf2)3催化剂催化下,室温下反应10分钟,氯苯的转化率就可分别达到87.6% 和 90.6%,反应产物的邻/对位比为4.3和4.8。并且这种催化剂与离子液体组成的催化体系很容易被回收,并可以连续使用5次以上。 相似文献
95.
2-Alkyl-3-(1-methyl-2-benzimidazolyl)-7-acyloxychromones were synthesized by the reaction of substituted or unsubstituted
2-(2,4-dihydroxyphenacyl)-1-methylbenzimidazoles with the acid chlorides and anhydrides of carboxylic acids. The products
were converted into 2-alkyl-7-hydroxychromones as a result of acid hydrolysis.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 26–30, January, 2008. 相似文献
96.
Trace levels analysisbenzalkonium chlorides (BAKs) in river water and wastewater treatment plants (WWTP) effluents were determined by capillary electrophoresis (CE) following solid‐phase extraction (SPE) and salting‐out extraction. Salting‐out extraction using an appropriate ratio of sodium chloride (NaCl) and acetonitrile (ACN) mixed with concentrated SPE elutant was capable of providing more than 500‐fold enhancement in detection sensitivity. The ratios of ACN and NaCl for salting‐out extraction were investigated and optimized. Matrix interference was eliminated by salting‐out extraction. Limits of quantitation of BAK homologues were achieved at 0.1 μg/L in 250 mL water samples. Recoveries of BAKs in various spiked water samples ranged from 70% to 84% with relative standard deviation (RSD) less than 9%. Trace amounts of total BAKs were detected in river water and WWTP effluent samples ranging from 27 to 145 μg/L at the first time by CE. 相似文献
97.
Grzegorz Mlostoń Marta Woźnicka Józef Drabowicz Anthony Linden Heinz Heimgartner 《Helvetica chimica acta》2008,91(8):1419-1429
The reactions of 3‐phenyl‐1‐azabicyclo[1.1.0]butane with α‐chlorosulfenyl chlorides and sulfinyl chlorides lead to the corresponding sulfenamides and sulfinamides, respectively, which possess an azetidine ring. It is proposed that a two‐step mechanism occurs involving an intermediate carbenium ion, which is formed by the addition of the electrophile at the N‐atom and cleavage of the N(1)? C(3) bond. The structures of 9b and 10b are established by X‐ray crystallography. 相似文献
98.
Xuejian Li Bangzhong Wang Dr. Dong Li Dr. Jinfeng Zhao Prof. Dr. Jingping Qu Prof. Dr. Yuhan Zhou 《European journal of organic chemistry》2023,26(15):e202201452
An efficient and environmentally friendly methodology for 3,3-dichlorination and 2-oxidation of indole derivatives is described. Using KI as promotor, MCl (M=K, Na) as chlorine source, and oxone as oxidant, the reaction proceeds smoothly affording various functionalized 3,3-dichloro-2-oxindoles in moderate to excellent yields. This strategy can also be extended to 3-substituted indoles. With a broad substrate scope, it is a practical approach to 3,3-disubstituted-2-oxindoles. 相似文献
99.
Gold(I)‐Catalyzed N‐Desulfonylative Amination versus N‐to‐O 1,5‐Sulfonyl Migration: A Versatile Approach to 1‐Azabicycloalkanes
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Solène Miaskiewicz Boris Gaillard Dr. Nicolas Kern Prof. Dr. Jean‐Marc Weibel Prof. Dr. Patrick Pale Dr. Aurélien Blanc 《Angewandte Chemie (International ed. in English)》2016,55(31):9088-9092
Valuable 1‐azabicycloalkane derivatives have been synthesized through a novel gold(I)‐catalyzed desulfonylative cyclization strategy. An ammoniumation reaction of ynones substituted at the 1‐position with an N‐sulfonyl azacycle took place in the presence of a gold cation by intramolecular cyclization of the disubstituted sulfonamide moiety onto the triple bond. Depending on the size of the heterocyclic ring and substitution of the substrates, two unprecedented forms of nucleophilic attack on the sulfonyl group were exploited, that is, a N‐desulfonylation in the presence of an external protic O nucleophile (37–87 %, 10 examples) and a unique N‐to‐O 1,5‐sulfonyl migration (60–98 %, 9 examples). 相似文献
100.
Xiao-Long Xu Jia Zhao Chun-Shan Lu Tong-Tong Zhang Xiao-Xia Di Shan-Chuan Gu Xiao-Nian Li 《中国化学快报》2016,27(6):822-826
Activated carbon-supported mercuric chloride(HgCl_2) is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl_2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl_2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides(Cs_xHg_yCl_(x+2y)) highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl_2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions. 相似文献