Electron‐impact promoted fragmentation of alkyl‐N‐(1‐phenylethyl)‐carbamates of primary, secondary and tertiary alcohols

Abstract
The mass spectra of twenty N‐alkyl‐(1‐phenylethyl)‐carbamates derived from primary, secondary and tertiary alcohols have been investigated using deuterium labeling and high resolution mass spectrometry. These derivatives are suitable for the determination of the isotopic purity of primary and secondary, but not of tertiary alcohols. Several of the primary and secondary alcohol derivatives yield an ion formally equivalent to the product ion of a McLafferty rearrangement. Deuterium labeling established, however, that the usual site specificity associated with the McLafferty rearrangement process was lacking in these carbamate derivatives. In addition a double hydrogen rearrangement process was observed in the mass spectra of several of the carbamates derived from tertiary alcohols.