A mild and efficient copper-catalyzed trifluoromethylation reaction which involves the cyclization of oximes has been developed. This method provides a convenient access to a variety of useful CF3-containing 4,5-dihydroisoxazoles by constructing a C–CF3 bond and a C–O bond in one step.
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...
Metal-free oxysulfonylation and aminosulfonylation of alkenyl oximes: synthesis of sulfonylated isoxazolines and cyclic nitrones
作者:Zhong-Qi Xu、Lin-Chuang Zheng、Lin Li、Lili Duan、Yue-Ming Li
DOI:10.1039/c8ob02879f
日期:——
Intramolecular oxysulfonylation of alkenyloximes was reported. Using iodine as the catalyst, TBHP as the oxidant, and sulfonyl hydrazides as the sulfonyl radical source, a variety of sulfonylated isoxazolines were obtained in moderate to excellent yields. Cyclicnitrones could also be readily obtained under the same conditions.
A novel and facile copper-catalyzed 5-endo-trig cyclization of ketoxime carboxylates for the synthesis of 2-arylpyrroles has been developed. The reaction tolerates a range of functional groups and is a practical procedure for rapid synthesis of 2-arylpyrroles in high yields under mild conditions.
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