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81.
Sulfonyl Ketenimines as Key Intermediates in One‐Pot Synthesis of N‐Sulfonyl‐2‐alkaneimidoyl Selenocyanates 下载免费PDF全文
Sulfonyl‐ketenimine intermediates, generated by the addition of Cu acetylides to sulfonyl azides, are trapped by KSeCN to afford N‐sulfonyl‐2‐alkaneimidoyl selenocyanates in moderate‐to‐good yields. 相似文献
82.
《化学:亚洲杂志》2017,12(18):2364-2368
A series of robust N‐heterocyclic carbene palladacycles have been successfully developed. These showed high catalytic activity and selectivity toward the challenging amination of N‐heteroaryl chlorides. Different primary and secondary amines were fully compatible with this catalytic system. Remarkably, no double amination products could be detected when primary amines were utilized in our catalytic transformation. Furthermore, the protocol has been successfully extended to synthesize rosiglitazone, a clinical drug for diabetes mellitus, highlighting its potential pharmaceutical feasibility. 相似文献
83.
Copper‐Catalyzed Tandem Synthesis of Functionalized Sulfonyl‐yn‐imines from Sodium Arylsulfinates,Trichloroacetonitrile, and Terminal Alkynes 下载免费PDF全文
A one‐pot synthesis of functionalized sulfonyl‐yn‐imines via a Cu‐catalyzed tandem reaction of sodium arylsulfinates, trichloroacetonitrile, and terminal alkynes has been developed. 相似文献
84.
Carbon‐based solid acid catalyst has been applied to catalyzing the synthesis of 4(3H)‐quinazolinones from the cyclization reaction of 2‐aminobenzamide with aroyl chlorides. The results showed that the catalyst was very efficient with the average yield over 85%. This carbon material with strong protonic acid sites as heterogeneous catalyst has some advantages such as high activity, strikingly simple work‐up procedure, non‐pollution, and reusability, which will contribute to the green process greatly. 相似文献
85.
(Methylchlorosilyl)methyldichlorophosphines have been synthesized by the reaction of [dimethy(diethylamino)silyl]- or [methyl-bis(diethylamino)silyl]methylmagnesium chlorides with PCl3 in ether at –40÷–20 °C and subsequent treatment of the reaction mixture with dry HCl. The structures of the compounds thus obtained have been studied by31P,1H, and13C NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 989–990, May, 1993. 相似文献
86.
A preparative method for the synthesis of novel N-phosphorylcarbonyl-and N-alkoxycarbonyltrichloroacetimidoylphosphonates from accessible pentachloroethyl isocyanate was developed. Factors that determine
the C/N-selectivity of the phosphorylation of trichloroacetimidoyl chlorides were revealed: phenyl substituents at the P atom
and an electron-withdrawing N-alkoxycarbonyl group in imidoyl chloride favored N-phosphorylation, while reactions with silyl phosphite gave exclusively
C-phosphorylation products.
Dedicated to the Corresponding Member of the Russian Academy of Sciences T. A. Mastryukova.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2563–2566, November, 2005. 相似文献
87.
V. A. Potapov A. A. Starkova S. V. Amosova A. I. Albanov B. V. Petrov 《Russian Chemical Bulletin》1998,47(10):2042-2044
The reactions of diethyl phosphite with alkaneselenenyl halides in chloroform at 20°C afforded the correspondingO,O-diethylSe-alkyl selenophosphates.
Dedicated to the memory of Academician M. I. Kabachnik on his 90th birthday.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2099–2101, October, 1998. 相似文献
88.
Lin Zeng Xiao-Qiang Guo Zai-Jun Yang Ya Gan Lian-Mei Chen Tai-Ran Kang 《Tetrahedron letters》2019,60(33):150943
A cascade cyclization/nucleophilic aromatic substitution (SNAr) reaction of α,β-unsaturated N-tosylhydrazones with N-heteroaryl chlorides was developed for the synthesis of N-heteroaryl pyrazole derivatives. This one-pot reaction provided bi(heteroaryl) derivatives in good to excellent yields and with excellent regioselectivity. The procedure is operationally simple and applicable to large-scale synthesis. 相似文献
89.
S-苄基硫磷酸酯和S-烷基硫磷酸酯在农药中有着重要的应用。 本文发展了一种无需催化剂,仅在碱作用下,氯代烷烃、硫粉以及氢亚磷酸酯三组份一步生成S-烷基硫磷酸酯的绿色经济方法,该反应可以在一步反应中同时构建磷—硫键和碳—硫键。 以苄氯及衍生物、硫粉、氢亚磷酸酯在碳酸铯的促进下,室温反应,共合成了17个S-苄基硫磷酸酯,产率为70%~99%。 同时,实现了脂肪链的氯代烃、硫粉和氢亚磷酸酯的反应,在三乙胺的促进下,在空气中60 ℃反应,共合成了13个S-烷基硫磷酸酯,产率为45%~93%。 本方法在合成上和工业上将具有较好的应用前景。 相似文献
90.
Ivanna Yu. Danyliuk Ruslan I. Vas’kevich Alla I. Vas'kevich Eduard B. Rusanov Mykhailo V. Vovk 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):156-162
Heterocyclization of N-(pyrazol-3-yl)styrylacetamides with arenesulfenyl chlorides yields the corresponding tetrahydrofuran-2-iminium perchlorates isolable after chromatography as trans-5-aryl-4-(arylthio)tetrahydrofuran-2-ones and 5-aryl-4-(arylthio)-1-(pyrazol-3-yl)pyrrolidin-2-ones, with the latter predominating. N-(Pyrazol-4-yl)styrylacetamides react under analogous conditions to give 5-aryl-4-(arylthio)-1-(pyrazol-4-yl)pyrrolidin-2-ones, 4-aryl-3-(arylthio)-4-chloro-N-(1-methylpyrazol-4-yl)butanamides, and tetrahydrofuran-2-iminium perchlorates which, when chromatographed, produce 5-aryl-4-(arylthio)dihydrofuran-2(3H)-ones and 4-aryl-3-(arylthio)-4-methoxy-N-(1-methyl-1H-pyrazol-4-yl)butanamides. 相似文献