Recyclable heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes: Practical access to vicinal tricarbonyls
作者:Wenli Hu、Bin Huang、Bingbo Niu、Mingzhong Cai
DOI:10.1016/j.tetlet.2021.152953
日期:2021.3
A highly efficient heterogeneous gold(I)-catalyzed oxidation of internal acylalkynes has been developed using 2,6-dichloropyridine N-oxide as the oxidant in dichloromethane (CH2Cl2) at room temperature, providing a novel and practical approach for the construction of diverse vicinal tricarbonyls such as α,β-diketoesters, 1,2,3-triketones, and α,β-diketoamides in good to excellent yields. The heterogeneous
The fluoride ion effect in the reactions of singlet oxygen with enols
作者:Harry H. Wasserman、James E. Pickett
DOI:10.1016/s0040-4020(01)96587-1
日期:——
The fluoride ion effect in the reactions of enolic systems with singletoxygen has been investigated. β-Dicarbonyl compounds yielded 1,2,3-tricarbonyl derivatives, some of which underwent further hydration, whereas α-diketones suffered oxidative decarboxylation to give open-chain aldehydo-acids or keto-acids.
Metal-free C–H methylation and acetylation of heteroarenes with PEG-400
作者:Vishal Suresh Kudale、Jeh-Jeng Wang
DOI:10.1039/d0gc01183e
日期:——
efficient route for methylation and acetylation of aza-heteroarenes using PEG-400 under O2 and TsOH·H2O for the first time by tuning the reaction conditions using a different set of starting materials. The key features of the current protocol are oxidative C–O and C–C bond scission under metal-free conditions with good functional group tolerance, and a broad substrate scope. The potential applicability
Substituted quinoxalyl-imidazolidine-2,4-diones, processes for their
申请人:Hoechst Aktiengesellschaft
公开号:US04943576A1
公开(公告)日:1990-07-24
Substituted quinoxalyl-imidazolidine-2,4-diones, processes for their preparation, their use as medicaments and pharmaceutical preparations 5-Quinoxalyl-imidazolidine-2,4-diones of the formula I ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 have the meanings given, and physiologically tolerated salts thereof and processes for their preparation are described. The compounds inhibit aldose reductase and can be used as medicaments.
Substituierte Chinoxalyl-imidazolidin-2,4-dione, Verfahren zu ihrer Herstellung, ihre Verwendung als Arzneimittel sowie pharmazeutische Präparate
申请人:HOECHST AKTIENGESELLSCHAFT
公开号:EP0288898A1
公开(公告)日:1988-11-02
5-Chinoxalyl-imidazolidin-2,4-dione der Formel I
in welcher R¹, R², R³, R⁴ und R⁵ angegebene Bedeutungen haben und deren physiologisch verträgliche Salze und Verfahren zu ihrer Herstellung werden beschrieben. Die Verbindungen hemmen die Aldose-Reduktase und können als Arzneimittel verwendet werden.
式 I 的 5-喹喔啉基咪唑烷-2,4-二酮
式中 R¹、R²、R³、R⁴ 和 R⁵ 的含义,以及它们的生理耐受盐和制备工艺。这些化合物能抑制醛糖还原酶,可用作医药产品。