Aromatic a,P-Unsubstituted Carboxylic Acids

Modifier Solvent Initial rate (mmol h g ee (%) Major enantiomer 

Many different types of support for palladium metal were tested, and those having appreciable amounts of both acidic and basic sites with a moderate specific surface area were found to be preferable [88]. Supports with a micropore structure proved not to be suitable because the active sites were situated inside the micro- 

Entry Additive (equiv.) Initial rate ro (mmolg h ) ee (%) 

A better base-catalyst exceeding Pd/TiO2 for this type of substrate was recently identified in a study using commercially available Pd/C catalysts [97]. Some examples of Pd/C catalysts, many of which are available worldwide and of stable quality, are listed in Table 10.3. Compared with Pd/TiO2, the dispersions were larger and the average diameter of the palladium particle smaller. When Pd/C was used as received for the hydrogenation of PCA, the product ee-value was low (as reported 

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