Iminoxyl Radical-Promoted Oxycyanation and Aminocyanation of Unactivated Alkenes: Synthesis of Cyano-Featured Isoxazolines and Cyclic Nitrones
作者:Fei Chen、Fei-Fei Zhu、Man Zhang、Rui-Hua Liu、Wei Yu、Bing Han
DOI:10.1021/acs.orglett.7b00826
日期:2017.6.16
oxidant, CuCN as the commercially available cyanating reagent, and pentamethyldiethylenetriamine (PMDETA) as the ligand. By using this protocol, a series of useful cyano-featured isoxazolines and cyclicnitrones were efficiently prepared.
Transition-metal-free oxychlorination of alkenyl oximes: in situ generated radicals with tert-butyl nitrite
作者:Xiao-Wei Zhang、Zu-Feng Xiao、Mei-Mei Wang、Yan-Jun Zhuang、Yan-Biao Kang
DOI:10.1039/c6ob01374k
日期:——
Oxychlorination of alkenyl oximes is harder compared to the analogous oxybromination or oxyiodination because of the difficulty associated with the formation of chlorine cations or radicals. A transition-metal-free oxychlorination of alkenyl oximes has been developed, using t-BuONO as a dual oxidant and AlCl3 as a chlorine source. This convenient and practical method has been used to construct chloroisoxazolines
A highly efficient manganese-promoted oxidative cyclization of unsaturated oximes to afford the corresponding 4,5-dihydroisoxazoline alcohols was developed. A very low loading (generally 0.1–0.2 mol-%) of Mn(acac)3 (acac = acetylacetonate) promoted the oxidative cyclization through the direct incorporation of molecular oxygen present in air (open flask) at room temperature.
Metal-Free Autoxidative Nitrooxylation of Alkenyl Oximes with Molecular Oxygen
作者:Xiao-Wei Zhang、Zu-Feng Xiao、Yan-Jun Zhuang、Mei-Mei Wang、Yan-Biao Kang
DOI:10.1002/adsc.201600147
日期:2016.6.16
A metal‐free aerobic autoxidativenitrooxylation of alkenyloximes mediated by tert‐butyl nitrite is described. Molecularoxygen is used as the oxidizing reagent, avoiding use of organic trapping reagents such as 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO). The desired products were obtained in generally high yields.