Bromination of ketones by palladium (II)‎. an asymmetric α-bromoketones catalytically synthesized by a mono palladium (II)‎ catalyst

Abstract EN

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 enantiomer 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, 1H, 13C-NMR and GC / MS.