The newly constructed reactor for hydrogenations in microwave fields allows to work out the syntheses up to 25 bar. This is shown for the synthesis of intermediates of active agents. In order to demonstrate the superiority of the microwave-assisted hydrogenation, the reactions are compared with classical hydrogenations. The following reactions were carried out: dearomatization, debenzylation, azide hydrogenation and the hydrogenation of strychnine. (C) 2005 Elsevier Ltd. All rights reserved.