Formation of highly substituted cyclopentanes from radical and anionic Michael cyclisations of α-iodo-γ- and -δ-lactones
摘要:
alpha-Iodos-delta- and -gamma-hexonolactones with alpha,beta-unsaturated esters developed from C-6 undergo both tributyltin hydride-induced radical and base catalysed anionic Michael cyclisations to form bicyclic lactones with very highly substituted homochiral cyclopentanes. The delta-lactones give cyclopentane products in which adjacent carbon substituents on the cyclopentane ring are cis to each other, whereas gamma-lactones give cyclopentanes in which the carbon chains are trans.
Formation of highly substituted cyclopentanes from radical and anionic Michael cyclisations of α-iodo-γ- and -δ-lactones
摘要:
alpha-Iodos-delta- and -gamma-hexonolactones with alpha,beta-unsaturated esters developed from C-6 undergo both tributyltin hydride-induced radical and base catalysed anionic Michael cyclisations to form bicyclic lactones with very highly substituted homochiral cyclopentanes. The delta-lactones give cyclopentane products in which adjacent carbon substituents on the cyclopentane ring are cis to each other, whereas gamma-lactones give cyclopentanes in which the carbon chains are trans.