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Identification of cyclobutane‐type dimers of substituted cinnamic acids by gas chromatography/mass spectrometry
Author(s) -
Stewart D.,
Robertson G. W.,
Morrison I. M.
Publication year - 1992
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/rcm.1290060110
Subject(s) - chemistry , dimer , substituent , cinnamic acid , fragmentation (computing) , mass spectrometry , cyclobutane , monomer , hydrogen bond , stereochemistry , ring (chemistry) , organic chemistry , chromatography , molecule , polymer , computer science , operating system
Abstract Substituted cinnamic acids were dimerized, under fluorescent or UV light, as a glassy coating on a vial then subsequently analysed by GC/MS. Mass Spectrometric analysis of the dimers formed by each acid allowed the assignment of the dimer as a truxillic or truxinic structure since these structures had distinctive fragmentation patterns; the breakdown of the truxillic acids involves a McLafferty rearrangment before fragmentation occurs, whereas the truxinic acids, which have both carboxy groups on one side and both aromatic groups on the other, fragment asymmetrically to give characteristic stilbene and dicarboxylate fragments. It is apparent from the results of the dimerization of the lcinnamic acids that, under the conditions used here, if the monomeric acid had the capacity for hydrogen bonding using the ring substituent as well as the carboxy group, the dimerization products would be overshelmingly truxillic in structure. However, if only the carboxy group could hydrogen bond, the products would be almost exclusively traxinic in structure.