| Abstract
| - At high [Cl-] (> 2.0 M), PdCl42- catalyzes the exchange of chiral allylic alcohols with hydroxy,methoxy, and phenyl to give chiral allyl-substituted olefins. With unsymmetrical olefins, isomerization occurs along with exchange. The hydroxyl exchange occurs in aqueous solution while theother exchanges are carried out in methanol solution. At low [Cl-] (0.1 M) oxidation to thecorresponding β-hydroxy-, methoxy-, and phenyl-substituted carbonyl compounds occurred. Theabsolute configurations of the oxidation and exchange products should be the same if the samemode of addition to the Pd(II)-π-complex is operative. The absolute configurations of the oxidationand exchange products for the phenylation reaction were the same, while for hydroxy and methoxythey were different. This result indicates methanol and water must have different stereochemistriesof addition at high and low [Cl-]. Thus, previous studies showing anti hydroxypalladation at high[Cl-] are not valid indicators of the stereochemistry at low [Cl-]. If anti addition occurs at high[Cl-], the addition must be syn at low [Cl-].
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