Facile access to 2-acyloxy-, aryloxy- and alkenyloxy-2H-azirines via an S_N2'-S_N2' cascade in 2-halo-2H-azirines

摘要

Various 2-oxygen-substituted 2H-azirine-2-carboxylic acid derivatives were synthesized in high yields under mild conditions from readily available precursors, 2-halo-2H-azirines and OH-reagents having pK_a values in the range of 3-10. This reaction is the first example of substitution at the azirine carbon atom for which an unusual S_N2'-S_N2' cascade mechanism was revealed.