Mild alpha-halogenation reactions of 1,3-dicarbonyl compounds catalyzed by Lewis acids.
Lewis acid Mg(ClO4)2, combined with NBS, in CH3CN or EtOAc provided mild and fast bromination of 1,3-dicarbonyl compounds. In particular, this protocol could be applied to the alpha-monobromination of alpha-unsubstituted beta-keto esters. Similar Lewis acid catalysis was also extended to the alpha-chlorination and iodination of 1,3-dicarbonyl compounds with NCS and NIS, respectively.
Yang
Dan
D
Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China. yangdan@hku.hk
Yan
Yi-Long
YL
Lui
Bob
B