Szmigielski Rafał, Danikiewicz Witold
Institute of Organic Chemistry, Polish Academy of Sciences ul. Kasprzaka 44/52, P.O. Box 58, 01-224 Warsaw 42, Poland.
J Mass Spectrom. 2005 Mar;40(3):331-41. doi: 10.1002/jms.790.
Unimolecular fragmentation patterns of the molecular ions of selected lactams and sultams bearing alkoxymethyl group at the nitrogen atom were studied. The main common fragmentation reaction observed for all compounds studied in this work is the elimination of an aldehyde molecule. This reaction is considered to proceed via two different mechanisms. For lactams, hydrogen rearrangement within an alkoxymethyl group is observed, which leads to the appropriate N-methyl derivatives. For sultams, transfer of the methyl group to the nitrogen and oxygen atoms, proceeding through an ion-neutral complex, dominates. Another important fragmentation channel characteristic exclusively for lactams is the loss of an alkyl radical. This process takes place within the N-alkoxymethyl moiety, yielding the appropriate protonated ion of N-formyllactams. This process is accompanied by relatively high kinetic energy release.
研究了在氮原子上带有烷氧基甲基的选定内酰胺和磺内酰胺分子离子的单分子碎裂模式。在本工作中所研究的所有化合物中观察到的主要常见碎裂反应是醛分子的消除。该反应被认为通过两种不同的机制进行。对于内酰胺，观察到烷氧基甲基内的氢重排，这导致相应的N-甲基衍生物。对于磺内酰胺，通过离子-中性复合物进行的甲基向氮和氧原子的转移占主导。另一个仅对内酰胺而言重要的碎裂通道是烷基自由基的损失。这个过程发生在N-烷氧基甲基部分内，产生相应的N-甲酰基内酰胺质子化离子。这个过程伴随着相对较高的动能释放。
