1,8-diazabicyclo[5.4.0]undec-7-ene: A remarkable base in the epoxidation of α,β-unsaturated-δ-lactones and other enones with anhydrous t-BuOOH

Article abstract of DOI:10.1016/0040-4020(95)00472-K

1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) has been studied for the epoxidation of electron deficient alkenes with anhydrous t-BuOOH (TBHP) in dichloroethane. Steric demands are higher than that for alkaline H₂O₂ DBU is recognised as a remarkable base in these oxidations as other bases such as triethyl amine, diisopropylethyl amine, and 1,4-diazabicyclo[2.2.2]octane (DABCO) are absolutely inefficient. DBU is effective in promoting the oxidation of α,β-unsaturated δ-lactones where most of conventional methods either fail or perform poor.