An unprecedented cyclizationreaction of donor–acceptor oxiranes with N,N′-disubstituted thioureas to construct trans-dihydropyrimidines is presented. Preliminary reaction mechanism studies demonstrated that the reaction underwent sequential cycloaddition/amine ester exchange/oxygen–sulfur exchange/desulfuration/Michael addition process. A wide range of trans-dihydropyrimidines were produced with high
<i>m</i>-CPBA/KOH: An Efficient Reagent for Nucleophilic Epoxidation of <i>g</i><i>em</i>-Deactivated Olefins
作者:J. L. García Ruano、Cristina Fajardo、Alberto Fraile、M. Rosario Martín
DOI:10.1021/jo050131o
日期:2005.5.1
The m-chloroperoxybenzoate anion (generated from m-CPBA and bases such as K2CO3 or KOH) is a highly efficient nucleophilic epoxidating reagent for strongly deactivated olefins containing two electron-withdrawing groups at the same carbon, under mild conditions which affect neither other double bonds nor electrophilic oxidizable centers such as sulfoxides.
Notes- Epoxidation of Diethyl Ethylidenemalonate by Alkaline Hydrogen Peroxide
作者:George Payne
DOI:10.1021/jo01094a623
日期:1959.12
POORKER, C. S.;KAGAN, J., TETRAHEDRON LETT., 1985, 26, N 52, 6405-6408
作者:POORKER, C. S.、KAGAN, J.
DOI:——
日期:——
KULKARNI B. D.; RAO A. S., INDIAN J. CHEM. <IJOC-AP>, 1975, 13, NO 10, 1097-1098