A Facile Epoxide Aminolysis Promoted by (<i>t</i>-BuO)₂Mg and Its Application to the Synthesis of Efinaconazole

A novel and efficient method for the aminolysis of trizole epoxides is described. This method consists of a facile ring opening of the epoxides mediated by t-BuOMgCl generated in situ from amine hydrochlorides and (t-BuO)2Mg. The desired β-amino alcohols were obtained in good yields without employing other heavy metals or precious catalysts. The optimized conditions were successfully applied to the synthesis of a number of potential triazole antifungal compounds as well as efinaconazole on up to a 700 g scale.