Isothiourea-Mediated One-Pot Synthesis of Functionalized Pyridines
摘要:
Acids to bases: The synthesis of 2,4,6-trisubstituted pyridines from (phenylthio)acetic acid and a range of α,β-unsaturated ketimines is reported. This process proceeds by intermolecular Michael addition/lactamization, thiophenol elimination, and N- to O-sulfonyl migration, giving 2-sulfonate-substituted pyridines which are readily derivatized to generate structural diversity.
Isothiourea-Mediated One-Pot Synthesis of Functionalized Pyridines
摘要:
Acids to bases: The synthesis of 2,4,6-trisubstituted pyridines from (phenylthio)acetic acid and a range of α,β-unsaturated ketimines is reported. This process proceeds by intermolecular Michael addition/lactamization, thiophenol elimination, and N- to O-sulfonyl migration, giving 2-sulfonate-substituted pyridines which are readily derivatized to generate structural diversity.
Base-Catalyzed Stereoselective Isomerization of Electron-Deficient Propargylic Alcohols to <i>E</i>-Enones
作者:John P. Sonye、Kazunori Koide
DOI:10.1021/jo060304p
日期:2006.8.1
stereoselective methods to isomerize electron-deficient propargylic alcohols to E-enones under mild conditions (EWG = electron-withdrawing group). Among weak bases we screened, catalytic (10−20 mol %) 1,4-diazabicyclo[2.2.2]octane (DABCO) was found to be effective in most cases. When the substrate is conjugated with an amide, the addition of sodium acetate catalyzed the isomerization.