Regioselective Synthesis of Nitrones by Decarboxylative Oxidation of<i>N</i>-Alkyl-<i>α</i>-amino Acids and Application to the Synthesis of 1-Azabicyclic Alkaloids
were prepared by catalytic oxidation of the corresponding chiral pyrrolidines in a regioselective manner. These chiral cyclic nitrones, 17 and 45 are versatile intermediates for the synthesis of optically active nitrogen heterocycles, since stereoselective additions of carbon nucleophiles to these chiral nitrones can be readily performed. Typically, ZnI2-mediated addition of ketene t-butyldimethylsilyl
Stereoselective Synthesis of Fluoroalkenoates and Fluorinated Isoxazolidinones: N-Substituents Governing the Dual Reactivity of Nitrones
作者:G. K. Surya Prakash、Zhe Zhang、Fang Wang、Martin Rahm、Chuanfa Ni、Marc Iuliucci、Ralf Haiges、George A. Olah
DOI:10.1002/chem.201303509
日期:2014.1.13
α‐Fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones are of vast interest due to their potential biological applications. We now demonstrate the syntheses of (E)‐α‐fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones by the reactions between nitrones and α‐fluoro‐α‐bromoacetate. By altering N‐substituents in nitrones, (E)‐α‐fluoroalkenoates and 4‐fluoro‐5‐isoxazolidinones can be achieved, respectively, with
Methyltrioxorhenium-Catalyzed Oxidation of Secondary and Primary Amines with Hydrogen Peroxide
作者:Shigekazu Yamazaki
DOI:10.1246/bcsj.70.877
日期:1997.4
The methyltrioxorhenium-catalyzed oxidation of secondaryamines and primaryamines with hydrogen peroxide has been carried out. The oxidation of secondaryamines afforded nitrones in good-to-excellent yield. Benzylamines were selectively oxidized to oximes, while general primary alkylamines possessing the α-C–H bond gave mixtures of oximes, nitroso dimers, and azoxy compounds.
Cyclohexanone monooxygenase catalyzed the oxidation of tertiary, secondary and hydroxylamines to N-oxides, hydroxylamines and nitrones respectively.
环己酮单加氧酶分别将叔胺,仲胺和羟胺氧化为N-氧化物,羟胺和硝酮。
Aliphatic nitro compounds chemistry: oximes–nitrones tunable production through directed tandem synthesis
作者:Foad Kazemi、Moosa Ramdar、Jamal Davarpanah
DOI:10.1007/s00706-018-2326-4
日期:2019.2
AbstractReduction of aliphatic nitro compounds in the presence of aldehydes and dialdehydes for tunable directedsynthesis of oximes, nitrones, nitrone–oximes, and dinitrones was reported. The slow and nonselective reduction of aliphatic nitro compounds was directed by condensation of in situ prepared alkylhydroxylamines with aromatic aldehydes. Mononitrones and dinitrones were synthesized at reflux
摘要据报导,在醛和二醛存在下还原脂肪族硝基化合物可调谐合成肟,硝酮,硝酮肟和二硝基酮。脂肪族硝基化合物的缓慢且非选择性的还原是通过原位制备的烷基羟胺与芳族醛的缩合来实现的。在四氢呋喃中,使用SnCl 2 ·2H 2 O和Na 2 CO 3分别在回流和55°C条件下合成单硝酮和二硝酮。研究发现,当使用二醛作为醛源时,催化量的羧酸(如3-苯基丙酸)的存在相对于硝酮肟和二肟而言,可以提高二硝酮的收率。 图形概要