Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)We developed an efficient fluorination protocol that converts easily accessible aziridines into beta-fluoroamines, which are important motifs in biologically active molecules. In contrast with traditional fluorination approaches, DMPU-HF has shown both higher reactivity and regioselectivity and good functional group tolerance; thus, a wide scope of beta-fluoroamines can now be accessed conveniently. The stereochemical behavior of the ring opening depends on the substitution pattern of the aziridine substrate.52911335313356National Institutes of Health [R15 GM101604-01]National Science Foundation [CHE-1401700]National Science Foundation of China [NSFC-21472018]Sao Paulo Research Foundation (FAPESP) [2015/08541-6]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)