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.
Three-Component Heterocyclization of <i>gem</i>-Bromofluorocyclopropanes with NOBF<sub>4</sub>: Access to 4-Fluoropyrimidine <i>N</i>-Oxides
作者:Kseniya N. Sedenkova、Elena B. Averina、Yuri K. Grishin、Andrei G. Kutateladze、Victor B. Rybakov、Tamara S. Kuznetsova、Nikolay S. Zefirov
DOI:10.1021/jo301880m
日期:2012.11.2
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.
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.