Description:
<jats:title>Abstract</jats:title><jats:p>As a model for the tritium labelling of peptides the catalytic deuteration of N‐acetyl‐DL‐3,4‐dehydroproline amide was investigated by means of mass spectrometric measurements. The unwanted incorporation of hydrogen instead of deuterium, found especially in the presence of water, was compensated partially by an incorporation of deuterium proceeding additionally to the saturation of the double bond. Both effects were most intensive in the presence of water and rose with ascending catalyst amounts and descending pH.</jats:p>