RESUMO
N-Mesitylene sulfonyl and N-tosyl aziridines have been identified as effective electrophiles in alkylation reactions of carbon acids catalyzed by the organic phosphorine base BEMP; yields of up to 99% for a range of pro-nucleophiles under mild reaction conditions are reported.
Assuntos
Aziridinas/química , Compostos Heterocíclicos com 1 Anel/química , Compostos Organofosforados/química , Alquilação , Catálise , Ésteres/síntese química , Ésteres/química , Estrutura Molecular , EstereoisomerismoRESUMO
The preparation of the (1-naphthyl)(trifluoromethyl) O-carboxy-anhydride 1 and its use as a chiral derivatizing agent with several alpha-chiral primary amines are reported. The very large Delta delta(RS) values observed in (1)H NMR have been correlated with a marked preference of the corresponding alpha-hydroxy-amides for the eclipsed conformation. In comparison, the related O-methylated amides are shown to adopt staggered conformations, which substantiates the critical role of intramolecular hydrogen bonding in maximizing the anisotropic effect.