Stephen K. Boyer

The heterogeneous enantioselective hydrodehalogenation of α,α-dichlorobenzazepinone-2: A unique case of substrate specificity.

Abstract The enantioselective hydrodehalogenation of α,α-dichlorobenzazepinone-2 with cinchona modified Pd- and Pt-catalysts was investigated using a random screening approach. The effect of important reaction parameters was determined and optimized. The best optical yields (50% ee) were obtained with a 5% Pd/BaSO 4 catalyst modified with cinchonine in THF with NBu 3 as HCl acceptor. Very high modifier and catalyst concentrations were necessary to get good optical yields and reasonable rates because the modifier decreases the catalyst activity. The absolute configuration of α-chlorobenzazepinone-2 was determined. Attempts to extend this enantioselective dehalogenation reaction to other α,α-dihalogen substituted acid derivatives were unsuccessful.

A mild and efficient process for detoxifying polychlorinated biphenyls

Abstract Polychlorinated biphenyls (PCBs) were effectively dechlorinated to biphenyl under mild conditions using an aqueous solution of sodium hypophosphite in the presence of a palladium catalyst.