Identification of 2,3-butanedione monoxime hydrogenation products by gas chromatography-mass spectrometry in an ion trap mass spectrometer.

The reduced products of 2,3-butanedinone monoxime by reaction with hydrogen in the presence of homogeneous catalysts were identified by gas chromatography coupled to an ion trap mass spectrometer operating either in the electron impact or chemical ionization mode. The major hydrogenation products were found to be several heterocyclic nitrogen-containing compounds: tetramethylpyrazine, 2,4-dimethyl-3-ethylpyrrole, 3,4,5-trimethylpyrazole, 2,5-dimethyl-1-propylpyrrole, 3-acetyl-2,4-dimethylpyrrole, 3,5-dimethyl-4-allypyrazole and tetramethylpyrazine N-monoxide.