Bromination of Ketones by Palladium(II). An Asymmetric α-Bromoketones Catalytically Synthesized by a Mono Palladium(II) Catalyst
نویسندگان
چکیده
The oxidation of ketones by monometallic [Pd(CH3CN)2(S)-Tol-BINAP](BF4)2 A or [Pd(CH3CN)2(S)-METBOX](BF4)2 B in aqueous THF containing copper(II) bromide produced chiral α-bromoketones. The α-bromoketone products were obtained with moderate to high enantiomeric excess (68-89% ee) and good isolated yields (70-90%). The highest optical purities were 89% ee for cycloheptanone. Catalyst B gave slightly higher enantioselectivities than catalyst A. All symmetric ketones gives only one product whereas, oxidation of 2-butanone gives the 3-bromo-2-butanone and 1-bromo-2-butanone. The α-bromoketone products were characterized by FTIR, H, C-NMR and GC/MS.
منابع مشابه
A highly active and selective palladium pincer catalyst for the formation of α-aryl ketones via cross-coupling.
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