Regioselective Halogenation at the γ-Position of β-Diketones Using Their BF2 Complexes.

Regioselective halogenation of β-diketones at the γ-methyl groups was achieved by using their BF2 complexes. γ-Halogenation was performed using N-halosuccinimide (NXS) in dichloromethane with catalytic triethylamine. These reactions produced a series of mono-, di-, and trihalogenated compounds depending on the NXS reactivity and the BF2 complex structure. Hydrolysis of the reaction products afforded γ-halogenated β-diketones, which can be used as metal ligands and key compounds in functional materials.