| Abstract
| - Palladium(II)-catalyzed aerobic oxidative amination of styrene with oxazolidinone proceeds withcatalyst-controlled regioselectivity: (CH3CN)2PdCl2 (1) and (Et3N)2PdCl2 (2) catalyze formation of the anti-Markovnikov and Markovnikov enecarbamate products, 3 and 4, respectively. Kinetic studies and deuteriumkinetic isotope effects demonstrate that these two reactions possess different rate-limiting steps, and thedata indicate that the product regiochemistry arises from the presence or absence of an effective Brønstedbase in the reaction. In the presence of a Brønsted base such as triethylamine or acetate, the kineticallypreferred Markovnikov aminopalladation adduct of styrene is trapped via rapid deprotonation of a zwitterionicintermediate and leads to formation of 4. In the absence of an effective Brønsted base, however, slowdeprotonation of this adduct enables aminopalladation to be reversible, and product formation proceedsthrough the thermodynamically preferred anti-Markovnikov aminopalladation adduct to yield 3.
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