Fragmentation of synthetic cannabinoids with an isopropyl group or a tert-butyl group ionized by electron impact and electrospray

This study described a fragmentation pattern of 21 synthetic cannabinoids with an isopropyl group or a tert-butyl group by electron impact ionization quadrupole mass spectrometry and electrospray ionization time-of-flight mass spectrometry in the positive mode. The compounds were categorized into four types according to substituted group such as a terminal amide and ester. The characteristic fragment ion in each group was obtained. The main common fragment ions for the two ionizations were formed by C-N cleavage of the amide group adjacent to the N-hetero rings. Additionally, the fragment ions indicated the difference in the basic structure as well as substituted group, which are useful for estimating the chemical structures of unknown compounds. Copyright (c) 2015 John Wiley & Sons, Ltd.