An efficient and water tolerant method for the synthesis ofβ-haloamines is described utilizing hydrated nickel（Ⅱ） halides （NiX_2ⅩnH_2O X = Cl,Br,I） and aziridines as starting materials.N-Tosylaziridines reacted with NiCl_2·6H_2O or NiI_2·6H_2O givingβ-chloro -orβ-iodoamines in high yields（73-99%） within a short time,but 10 mol%of n-Bu_4NBr should be added in the reactions of N-tosylaziridines with NiBr_2·3H_2O in order to obtain the high yields of correspondingβ-bromoamines.Solvent played an important role in the reactions.The proper solvent for the reaction of NiCl_2·6H_2O was DMF,while NiBr_2·3H_2O or NiI_2·6H_2O proceeded well in 1,4-dioxane.
Ring opening of aziridine with dialkyl amine took place readily in the presence of catalytic amounts of tri-n-butylphosphane （10 mol%） in the mixture of CH3CN/H20 （10：1）, giving corresponding vicinal diamines in mediate to high yields （58-95%） with good regioselectivitie, while aromatic secondary amine could not react under the same conditions. Tri-n-butylphosphane exhibited different catalytic selectivity to amines from Lewis acid catalysts.
