Mass spectral fragmentation pattern of 3‐(2′‐hydroxyethyl)quinolin‐2(1 H )‐one and its derivatives

Fragmentation patterns resulting from electron impact ionization of 3‐(2′‐hydroxyethyl)quinolin‐2(1 H )‐one, three of its monosubstituted derivatives and four of its disubstituted derivatives were studied. The molecular ion of quinolinone‐2‐etbanol undergoes initial fragmentation with the loss of OH · , H 2 O, CO, · CHO, CH 2 O, CH 2 OH · , CH 2 CHOH and HCNO species. The [M – CHO] + ion is tentatively suggested to have been formed by the expulsion of H · from the [M – CO] +· ion and the [M ‐ CHO] + peak may be considered as diagnostic of a 2‐quinolone‐3‐ethanol.