1631-26-1Relevant articles and documents
Phosphine-catalyzed [4+1] annulation of 1,3-(aza)dienes with maleimides: Highly efficient construction of azaspiro[4.4]nonenes
Yang, Mei,Wang, Tianyi,Cao, Shixuan,He, Zhengjie
, p. 13506 - 13509 (2014)
Phosphine-catalyzed [4+1] annulation of electron-deficient 1,3-dienes or 1,3-azadienes with maleimides has been successfully developed under very mild conditions, providing a convenient and highly efficient method for constructing 2-azaspiro[4.4]nonenes and 1,7-diazaspiro[4.4]nonenes. This reaction represents the first example of [4+1] cyclization between electron-deficient 4π-conjugated systems and non-allylic phosphorus ylides.
An efficient protocol for the synthesis of N-Alkyl- and N-Arylimides using the lewis acidic ionic liquid choline chloride-2ZnCl2
Xiea, You-Teng,Houb, Rei-Sheu,Wangb, Huey-Min,Kangc, Iou-Jiun,Chena, Ling-Ching
, p. 839 - 842 (2009)
Lewis acidic ionic liquid choline chloride-2ZnCl2 is shown to be for the first time an excellentmedium and efficient catalyst for the synthesis of N-alkyl- and N-arylimides in good yields under mild conditions.
Preparation method of medical intermediate N-benzyl-3-pyrroline
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Paragraph 0030; 0042-0043; 0045-0046; 0048-0049, (2021/08/28)
The invention discloses a preparation method of a medical intermediate N-benzyl-3-pyrroline. The method comprises the following steps: adding a proper amount of benzylamine, maleic anhydride and a reaction medium into a reaction flask, and stirring for reaction to obtain a diamide compound; and dissolving a diamide compound in tetrahydrofuran, dropwise adding a proper amount of 70% red aluminum solution, and reducing the diamide compound to obtain N-benzyl-3-pyrroline; The method is low in raw material cost, simple in process step, high in yield, small in pollution, high in product purity and suitable for industrial production.
Oxidative Cleavage of Indoles Mediated by Urea Hydrogen Peroxide or H2O2 in Polar Solvents
Llopis, Natalia,Gisbert, Patricia,Baeza, Alejandro
supporting information, p. 3245 - 3249 (2021/06/08)
The oxidative cleavage of indoles (Witkop oxidation) involving the use of H2O2 or urea hydrogen peroxide in combination with a polar solvent has been described. Among these solvents, 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) stands out as the one affording the corresponding 2-ketoacetanilides generally in higher yields The protocol described has also enabled the oxidation of different pyrroles and furans derivatives. Furthermore, the procedure was implemented in a larger-scale and HFIP was distilled from the reaction mixture and reused (up to 4 cycles) without a significant detriment in the reaction outcome, which remarks its sustainability and applicability. (Figure presented.).