Premium
The mass spectra of the 4,4‐dimethyloxazoline derivatives of some conjugated hydroxy ene‐yne C 17 and C 18 fatty acids
Author(s) -
Spitzer Volker
Publication year - 1996
Publication title -
journal of the american oil chemists' society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.512
H-Index - 117
eISSN - 1558-9331
pISSN - 0003-021X
DOI - 10.1007/bf02523924
Subject(s) - chemistry , conjugated system , oxazoline , ene reaction , molecule , ion , mass spectrum , stereochemistry , cleavage (geology) , fatty acid , polyatomic ion , medicinal chemistry , organic chemistry , catalysis , materials science , polymer , fracture (geology) , composite material
The mass spectra of the 4,4‐dimethyloxazoline derivatives from various fatty acids with a hydroxy group in conjugation with conjugated double‐triple bonds (7‐hydroxy‐trans‐10‐heptadecene‐8‐ynoic acid; 7‐hydroxy‐ trans ‐10, 16‐heptadecadiene‐8‐ynoic acid; 8‐hydroxy‐ rans ‐11‐octadecene‐9‐ynoic acid; 8‐hydroxy‐ trans ‐11, 17‐octadecadiene‐9‐ynoic acid) have been examined and compared with their analogous nonhydroxy derivatives. The position of the hydroxy group was unequivocally proven by characteristic odd‐numbered fragment peaks, explainable by α‐cleavage at the hydroxy group at the oxazoline end of the molecule. The weak ions produced by α‐cleavage at the other side of the hydroxy group indicated that the hydroxy group must be in conjugation with the ene‐yne system. Fragments that allow one to distinguish between ene‐yne or yne‐ene systems were absent. In conjunction, the weak molecular ion and the more intense M‐18 ion could confirm the molecular weight of each fatty acid.