Sterically congested chiral activated aziridines: Synthesis of both 2,3-cis- and 2,3-trans-2-alkenyl-3-alkylaziridines from common intermediates

Abstract Whereas treatment of the allylic mesylates of N -protected 2-alkyl-4-amino-( E )-2-alken-1-ols with sodium hydride in DMF yields exclusively the corresponding 2,3- trans -2-alkenyl-3-alkylaziridines, exposure of the methyl carbonates of N -protected 2-alkyl-4-amino-( E )-2-alken-1-ols to Pd(PPh 3 ) 4 (5–20 mol%) in THF or 1,4-dioxane affords predominantly the corresponding 2,3- cis -2-alkenyl-3-alkylaziridines. These reactions can be used to synthesize either of two diastereomers from single common intermediates.