Reaction of iodonium ylides of 1,3-dicarbonyl compounds with HF reagents.
Reaction of dibenzoylmethane with (diacetoxyiodo)benzene in the presence of KOH in MeCN quantitatively gave the corresponding iodonium ylide, which was treated with a HF reagent to afford the corresponding 2-fluorinated dibenzoylmethane in 14-50% yields. The similar reaction of the iodonium ylides obtained from 1-phenylbutan-1,3-dione, ethyl benzoylacetate, and ethyl p-nitrobenzoylacetate with TEA·3HF gave the corresponding fluorinated products in 17-34% yields. It is suggested that the fluorinated products were formed through the C-protonation of the ylide, followed by displacement with fluoride ion. The same reaction of the iodonium ylide of dibenzoylmethane with concentrated HCl gave the corresponding chlorinated product in 45% yield.
Department of Chemistry and Applied Chemistry, Graduate School of Science and Engineering, Saga University, Honjo-machi, Saga 840-8502, Japan.
Keisuke
K
Gondo
Tsugio
T
Kitamura
D006858:Hydrofluoric Acid / Q000737:chemistry*; D007202:Indicators and Reagents; D009861:Onium Compounds / Q000737:chemistry*
D007202:Indicators and Reagents; D009861:Onium Compounds; D006858:Hydrofluoric Acid