In this work, trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxalane (DHPDMDO)/NH I has been used as, powerful, nearly green, effective and inexpensive oxidant for oxidative aromatization of isoxazolines and 2-pyrazolines to corresponding isoxazoles and 2pyrazoles in the presence of catalytic amount of acetic acid at room temperature in water/MeCN. All products were obtained in high yields and good purity within short time by an easy work-up.
