Complementary regioselective synthesis of 3,5-disubstituted isoxazoles from ynones
作者:Xiaochen Liu、Dongsub Hong、Zhigang She、William H. Hersh、Barney Yoo、Yu Chen
DOI:10.1016/j.tet.2018.09.043
日期:2018.11
dehydration. The two routes are not only both highly regioselective, but also complementary to each other as a pair of regioisomeric 3,5-disubstituted isoxazoles are readily prepared from one single ynone substrate. The efficiency of the two routes are further evaluated and demonstrated in the synthesis of three representative 3,5-disubstituted isoxazoles.
5‐Hydroxy‐4,5‐dihydroisoxazoles were synthesized conveniently in good yields by tandem conjugate addition‐cyclization reaction of acetylenic ketones and hydroxylamine hydrochloride salt.
通过乙炔酮和盐酸羟胺盐的共轭加成-环化反应可以方便地以高收率合成5-羟基-4,5-二氢异恶唑。
TEMPO‐Mediated Selective Synthesis of Isoxazolines, 5‐Hydroxy‐2‐isoxazolines, and Isoxazoles via Aliphatic
<i>δ</i>
‐C(sp3)‐H Bond Oxidation of Oximes
Three heterocycles from one starting material: A divergent method for the synthesis of isoxazolines, isoxazoles, and 5-hydroxy-2-isoxazolines from oximes is developed using TEMPO as a radical initiator. Oxidants control the selectivity of the product formations.
来自一种原料的三个杂环:使用 TEMPO 作为自由基引发剂开发了一种从肟合成异恶唑啉、异恶唑和 5-羟基-2-异恶唑啉的不同方法。氧化剂控制产物形成的选择性。
Efficient and Regioselective Synthesis of 5-Hydroxy-2-isoxazolines: Versatile Synthons for Isoxazoles, β-Lactams, and γ-Amino Alcohols
作者:Shibing Tang、Jinmei He、Yongquan Sun、Liuer He、Xuegong She
DOI:10.1021/jo1000065
日期:2010.3.19
An efficient and highly regioselective protocol was developed for the preparation of 5-hydroxy-2-isoxazolines, which have been proved to be versatile synthons for isoxazles, beta-hydroxy oximes, and gamma-amino alcohols. beta-Lactams, commonly embedded in the skeletons of bioactive natural products, were also synthesized in two steps from beta-hydroxy oximes, providing a new strategy for the synthesis of this kind of compounds.
Escale,R. et al., Bulletin de la Societe Chimique de France, 1974, p. 725 - 733