Three-Component Heterocyclization of gem-Bromofluorocyclopropanes with NOBF4: Access to 4-Fluoropyrimidine N-Oxides
摘要:
Novel three-component heterocyclization involving gem-bromofluorocyclopropanes, nitrosyl tetrafluoroborate, and a molecule of the solvent (nitrile) yielding previously unknown fluorinated pyrimidine N-oxides is described. A two-step synthetic approach to 4-fluoropyrimidine N-oxides from alkenes under mild conditions is developed using this reaction. Mechanistic aspects of the heterocyclization are discussed.
(2-Fluoroallyl)pyridinium tetrafluoroborates: novel fluorinated electrophiles for Pd-catalyzed allylic substitution
作者:Angelina Yu. Bobrova、Maxim A. Novikov、Yury V. Tomilov
DOI:10.1039/d1ob00567g
日期:——
An efficient two-step approach to 2-fluoroallyl amines was developed that involves the synthesis of (2-fluoroallyl)pyridinium tetrafluoroborates from readily available gem-bromofluorocyclopropanes and the application of the former as novel and stable 2-fluoroallyl electrophiles for Pd-catalyzed allylic substitution.
Synthesis of 5-fluoro- and 5-bromoalkylisoxazoles via nitrosation of 1,1-dihalocyclopropanes with sulfur trioxide activated nitrosyl chloride
作者:Oksana B. Bondarenko、Aleksandr A. Vinogradov、Arseniy I. Komarov、Andrei S. Smirnov、Nikolai V. Zyk
DOI:10.1016/j.jfluchem.2016.03.003
日期:2016.5
A method for the synthesis of 5-fluoro- and 5-bromoalkylisoxazoles via nitrosation of alkylated gem-dihalocyclopropanes with a nitrosyl chloride sulfur trioxide adduct has been developed. In the case of bromofluorocyclopropanes the reaction proceeded with excellent chemoselectivity thus providing exclusively 5-fluoroisoxazoles.