title: The replacement of trideuteromethyl by methyl groups when using methane as a reagent gas in chemical ionization mass spectrometry.
abstract: The methane chemical ionization spectra of a number of tertiary and quaternary amines with a N-trideuteromethyl group show substitution of this group by methyl. The isotopic purity of the original amines was shown to be greater than 99% using ammonia as a reagent gas.
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D003903:Deuterium; D007202:Indicators and Reagents; D007477:Ions; D013058:Mass Spectrometry / Q000379:methods*; D008697:Methane; D011413:Propantheline / Q000031:analogs & derivatives / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D007477:Ions; D011413:Propantheline; D003903:Deuterium; D008697:Methane