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。
Cyclocondensation of Hydroxylamine with 1,3-Bis(het)arylmonothio 1,3-Diketones and 1,3-Bis(het)aryl-3-(methylthio)-2-propenones: Synthesis of 3,5-Bis(het)arylisoxazoles with Complementary Regioselectivity
作者:Byregowda Raghava、Gangajji Parameshwarappa、Anand Acharya、Toreshettahally R. Swaroop、Kanchugarakoppal S. Rangappa、Hiriyakkanavar Ila
DOI:10.1002/ejoc.201301667
日期:2014.3
monothio-substituted 1,3-diketones is installed at the 3-position. On the other hand, the reaction of hydroxylamine hydrochloride with 3-(methylthio)-1,3-bis(het)aryl-2-propenones 2 in the presence of barium hydroxide in refluxing ethanol gave 3,5-bis(het)arylisoxazoles 6 with complementary regioselectivity in high yields. A probable mechanism for the formation of regioisomeric isoxazoles 5 and 6 from precursors
Copper-catalyzed aerobic oxidative C–O bond formation for the synthesis of 3,5-disubstituted isoxazoles from enone oximes
作者:Yadong Sun、Ablimit Abdukader、Haiyan Zhang、Wanle Yang、Chenjiang Liu
DOI:10.1039/c7ra11436b
日期:——
oxidative coupling reaction of enone oximes using a catalytic quantity of Cu(OAc)2. This method features an inexpensive metal catalyst, molecular oxygen as a green oxidant, good functional group tolerance and readily available starting materials. This attractive method for the synthesis of isoxazole derivatives is of great significance due to the product's versatile reactivity for further transformations.