Synthesis of δ‐Lactones from Glutaraldehyde

Abstract

Abstract A novel and general synthesis of δ‐lactones from glutaraldehyde is described. The dialdehyde is first reacted with an alkyl or substituted alkyl Grignard reagent to afford a δ‐hydroxyaldehyde in good yield. These aldehydes exist preferentially in the cyclic hemiacetal form (δ‐lactols). Oxidation of the latter compounds to give δ‐lactones is readily achieved with silver oxide or bromine. The δ‐lactols and δ‐lactones serve as intermediates for the total synthesis of steroids.