Abstract
Polyurea microcapsules containing palladium acetate have been
used in a range of catalytic hydrogenation reactions.
Key words
palladium - catalysis - hydrogenations - polyurea - microcapsules
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9 Samples of Pd EnCatTM can
be obtained on request from Avecia U. K.
10 All hydrogenation reactions were carried
out using Pd EnCatTM that had been pre-reduced under
H2 (50 bar) for two days. This pre-reduction is required
for high activity and reduced reaction times.
11 The reduction of 4-nitrotoluene (entry
6, method A) to p -toluidine using Pd/C
was complete in 1 h. Using Pd/C under the same conditions
used for entry 14 resulted in the reduction and complete removal
of the benzyloxy group.
12 The veracity of this statement has
not been established on reaction scales greater than those commonly
employed in research laboratories.
