A mild, palladium-catalyzed method for the dehydrohalogenation of alkyl bromides: synthetic and mechanistic studies.

ABSTRACT: We have exploited a typically undesired elementary step in cross-coupling reactions, ?-hydride elimination, to accomplish palladium-catalyzed dehydrohalogenations of alkyl bromides to form terminal olefins. We have applied this method, which proceeds in excellent yield at room temperature in the presence of a variety of functional groups, to a formal total synthesis of (R)-mevalonolactone. Our mechanistic studies have established that the rate-determining step can vary with the structure of the alkyl bromide and, most significantly, that L(2)PdHBr (L = phosphine), an intermediate that is often invoked in palladium-catalyzed processes such as the Heck reaction, is not an intermediate in the active catalytic cycle.

SUBMITTER: Bissember AC 

PROVIDER: S-EPMC3432975 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature