Zinc Iodide-Mediated Direct Synthesis of 2,3-Dihydroisoxazoles from Alkynes and Nitrones
作者:Zu-Feng Xiao、Ting-Hui Ding、Sheng-Wei Mao、Xiao-Shan Ning、Yan-Biao Kang
DOI:10.1002/adsc.201600044
日期:2016.6.2
A zinc diiodide (ZnI2)‐mediated directsynthesis of 2,3‐dihydroisoxazoles via a [3+2] cycloaddition reaction of the nitrones and non‐electron‐deficient terminalalkynes has been developed. This method was applied in the formal synthesis of HPA‐12 and aminoglucose.
Synthesis of stable isoxazolines by [3+2] cycloaddition of oxaziridines with alkynes
作者:Marilena Fabio、Ludovico Ronzini、Luigino Troisi
DOI:10.1016/j.tet.2008.03.092
日期:2008.5
N-Alkyl substituted oxaziridines undergo a [3+2] cycloaddition reaction with a variety of terminal alkynes to give the product isoxazolines, whose stability appears to depend on the electronic properties of the groups on the C-3 and C-5 positions. The presence of an electron withdrawing group on C-5 and/or an electron donating group on C-3 causes isomerization of the isoxazolines to β-amino enones
Synthesis of 4-Isoxazolines through Gold(I)-Catalyzed Cyclization of Propargylic <i>N</i>-Hydroxylamines
作者:B. Chandrasekhar、Sewon Ahn、Jae-Sang Ryu
DOI:10.1021/acs.joc.6b01499
日期:2016.8.5
New catalytic methods for the synthesis of 4-isoxazolines have been developed via catalytic intramolecularcyclizations of propargylic N-hydroxylamines. The reactions proceed rapidly in less than 1 h at room temperature in the presence of 5 mol % (PPh3)AuCl/5 mol % AgOTf or 5 mol % (PPh3)AuNTf2. This process features an efficient route to 4-isoxazolines with high yields, short reaction times, and mild