Mild oxidative aromatization of 1,4-dihydropyridines with trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxalane promoted by ammonium bromide/HOAc in water/MeCN

Trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxalane (DHPDMDO)/NH 4 Br/HOAc has been used as a new and effective oxidant for oxidative aromatization of 1,4-dihydropyridines to the corresponding pyridines in the presence of a catalytic amount of acetic acid at room temperature in water/MeCN in good yields within short times.