1206479-02-8Relevant articles and documents
Acyclic nitronate olefin cycloaddition (ANOC): regio- And stereospecific synthesis of isoxazolines
Ma, Liang,Kou, Luyao,Jin, Feng,Cheng, Xionglve,Tao, Suyan,Jiang, Gangzhong,Bao, Xiaoguang,Wan, Xiaobing
, p. 774 - 779 (2021)
We report the first demonstrations of intra- and intermolecular acyclic nitronate olefin cycloaddition (ANOC) reactions that enable the highly efficient syntheses of isoxazolines bearing various functional groups. This general approach to accessing γ-lactone fused isoxazolines was hitherto unprecedented. The room temperature transformations reported herein exhibit wide substrate scopes, as evidenced by more than 70 examples, including the generation of five tricyclic isoxazolines. The robustness of this methodology was confirmed by a series of trials that afforded highly functionalized isoxazolines. Both experimental results and density functional theory calculations indicate that these transformations proceed via the in situ formation of acyclic nitronates together with concerted [3+2] cycloaddition and tert-butyloxy group elimination processes to give regio- and stereospecificity. This journal is
Synthesis of Isoxazolines and Oxazines by Electrochemical Intermolecular [2 + 1 + n] Annulation: Diazo Compounds Act as Radical Acceptors
Xiong, Mingteng,Liang, Xiao,Gao, Zhan,Lei, Aiwen,Pan, Yuanjiang
supporting information, p. 9300 - 9305 (2019/11/20)
Reported herein is an unprecedented synthesis of isoxazolines and oxazines through electrochemical intermolecular annulation of alkenes with tert-butyl nitrite, in which diazo compounds serve as radical acceptors. Notably, [2 + 1 + 2] and [2 + 1 + 3] annulations occur when styrenes and allylbenzenes are used as substrates, respectively. The latter reaction undergoes group migration to form more stable radical, manifesting radical route instead of conventional 1,3-dipolar cycloaddition occurs. Moreover, scale-up experiments suggest the potential application value of these transformations in industry.
