A New Synthesis of γ-Butyrolactones via AuCl3- or Hg(II)-Catalyzed Intramolecular Hydroalkoxylation of 4-Bromo-3-yn-1-ols
摘要:
An efficient conversion of 4-bromo-3-yn-1-ols to gamma-butyrolactones via AuCl3-catalyzed electrophilic cyclization (hydroxyl-assisted regioselective hydration) in wet toluene is described. Various secondary and tertiary alcohols including benzylic systems were found to be equally reactive with moderate to excellent yields obtained in all cases.
A system for in situ regeneration of SmI2 from SmI3 is described which allows the annulation of ketones to γ-lactones, the deoxygenation of oxiranes to olefins and radical π-cyclization to be conducted with 10 mole % SmI2.
Reaction of cycloalkanones with methyl 3-bromopropionate and Sml2 afforded formation of spiroanellated γ-lactones, pinacols and unprecedented 3-(1-hydroxycycloalkyl)-1-oxaspiro[n,m]alkan-2-ones.
γ-Substituted butyrolactones from acrolein and carbonyl compounds
作者:José Barluenga、José R. Fernández、Miguel Yus
DOI:10.1039/c39870001534
日期:——
The lithiation of 3-chloropropanal diethyl acetal (easily prepared fromacrolein) at –78 °C with lithium naphthalenide followed by reaction with various carbonylcompounds, and final oxidation with m-chloroperbenzoic acid leads to γ-substitutedbutyrolactones.