Synthesis of 2,7-Diamino-4,5-Epoxysuberic Acid Derivatives

The epoxidation of 2,7-diaminooct-4-enedioic acid derivatives with different steric requirements at the homoallylic positions has been studied. Four readily available unsaturated bis-amino esters were used as model substrates for the synthesis of 2,7-diamino-4,5-epoxysuberic esters. The study revealed a reduced reactivity of all the unsaturated compounds towards epoxidation, but particularly of the most crowded one. Moderate stereoselectivity was observed in the epoxidation of C2-symmetric chiral unsaturated bis-a-amino esters. All substrates were converted to the corresponding epoxides in high yields using an excess of Oxone®/acetone.