New synthetic routes towards various α-fluorinated aryl ketones and their enantioselective reductions using baker's yeast

Highly electrophilic dichlorofluoromethyl aryl ketones were obtained by oxidation of dichlorofluoromethyl aryl alcohols. Sub-sequent dechlorination of these ketones using sodium formaldehyde sulfoxylate (Rongalite) and reductive dehalogenating system SnCl2/Al let to various fluoromethyl aryl ketones and chlorofluoromethyl aryl ketones, respectively. Asymmetric reductions of these fluorinated ketones using the inexpensive baker's yeast produced the corresponding fluoromethyl aryl alcohols with alcohols with different enantioselectivities. (c) 2006 published by Elsevier Ltd.