Collect. Czech. Chem. Commun. 1984, 49, 2816-2818

Anomalous mass spectra of some aporphine methiodides

Ladislav Dolejš

Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


Methiodides of corydine, isocorydine and isothebaine are O-demethylated in the ionic source of the mass spectrometer by hydrogen iodide formed on pyrolysis of the sample. The reaction is common in aporphine methiodides substituted in positions 1 and 11 by one hydroxyl and one methoxyl group. The behaviour can be explained by the combined action of the hydrogen bridge and steric strain.