Copper-Catalyzed Oxyazidation of Unactivated Alkenes: A Facile Synthesis of Isoxazolines Featuring an Azido Substituent
摘要:
A novel and efficient Cu(OAc)(2)-catalyzed oxyazidation of unactivated alkenes was developed. The reactions are easy to conduct, occur under mild conditions, and form azido-substituted isoxazolines in good yields.
Copper-mediated oxysulfonylation of alkenyl oximes with sodium sulfinates: a facile synthesis of isoxazolines featuring a sulfone substituent
作者:Li-Jing Wang、Manman Chen、Lin Qi、Zhidong Xu、Wei Li
DOI:10.1039/c7cc00090a
日期:——
A novel and efficient Cu(OAc)2-mediated oxysulfonylation of alkenyl oximes with sodium sulfonates was developed. The reactions are easy to conduct, occur under mild conditions, and form a broad range of...
BF<sub>3</sub>·OEt<sub>2</sub>-mediated cyclization of β,γ-unsaturated oximes and hydrazones with <i>N</i>-(arylthio/arylseleno)succinimides: an efficient approach to synthesize isoxazoles or dihydropyrazoles
作者:Wei Yu、Shichao Yang、Pei-Long Wang、Pinhua Li、Hongji Li
DOI:10.1039/d0ob01388a
日期:——
A highly efficient BF3·OEt2-mediated cyclization of β,γ-unsaturatedoximes and tosylhydrazones with N-(arylthio/arylseleno)succinimides has been established for the construction of N-heterocycles in a one-step manner. This metal-free cyclization provides direct access to isoxazoles and dihydropyrazoles in good to excellent yields at room temperature. The mechanistic experiments support the formation
Room temperature iron(<scp>ii</scp>)-catalyzed radical cyclization of unsaturated oximes with hypervalent iodine reagents
作者:Shichao Yang、Hongji Li、Pinhua Li、Jingya Yang、Lei Wang
DOI:10.1039/c9ob02424g
日期:——
Here, we disclose an iron(ii)-catalyzed I-O bond cleavage of Koser's hypervalent iodine reagents (HIRs) that initiated the radical cyclization of unsaturated oximes at room temperature. This strategy is successfully applied for the construction of the isoxazoline backbone in an efficient manner. In particular, the direct introduction of a TsO group into products facilitates their late-stage transformations
A copper-catalyzed oxydifluoroalkylation of β,γ-unsaturatedoximes has been developed. This reaction proceeded through a cascade of difluoroalkylation of alkene followed by nucleophilic attack of the hydroxyl group of oximes. This protocol features mild reaction conditions, low-cost catalyst, and broad substrate scope, which provides a facile method to synthesize isoxazolines with a fluorinated sidechain
A new electrochemical method for the synthesis of 2-isoxazolines is reported. The reaction operates under atmospheric conditions and tolerates air and moisture. The use of potassium bromide as both electrolyte and bromine source precludes the need for toxic, air-sensitive inorganic oxidants or transition metal catalysts.