Facile preparation of N-protected 2-alkylidene-1,3-imidazolidines

Stereoselective preparation of unsymmetrically protected 2-alkylidene-1,3-imidazolidines was achieved by the reaction of N,N′-protected ethylenediamine, bromopropynamide, and K3PO4 in hot DMF. When N-protected aminoethanol was used in place of the protected ethylenediamine, an oxazolidine derivative was produced.