An efficient and divergent one-pot synthesis of α,α-dihaloamides from readily available β-oxoamides based on the selection of reaction conditions is reported. α,α-Dihalo-β-oxo amides were produced by treating β-oxoamides with N-chlorosuccinimide (NCS) or N-bromosuccinimide (NBS) in water at room temperature, whereas α,α-dihaloacetamides were synthesized by subjecting β-oxoamides to NCS or NBS in
alpha,alpha-Dihalo-N-arylacetamides are commonly used as intermediates in various organic reactions. In the study described here, a catalytic synthesis of alpha,alpha-dihalo-N-arylacetamides from beta-oxo amides was developed using zwitterionic catalysts and N-halosuccinimides as the halogen sources. The corresponding alpha,alpha-dihalo-N-arylacetamides were obtained in good to excellent yields, and no aromatic halogenated side products were detected. The reaction conditions were mild, and no strong base or acid was required.
Collet, Bulletin de la Societe Chimique de France, 1902, vol. <3> 27, p. 542