Fused-ring tropylium ion formation and fragmentation

✍ Scribed by Laurel J. Standley; Ronald A. Hites

• Book ID: 102965804
• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 538 KB
• Volume: 24
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/oms.1210240909

✦ Synopsis

Fused-ring tropylium ions, formed in the electron impact mass spectra of methyl phenanthrenes and methyl anthracenes were studied by mass spectrometric and computational methods These ions form through a cyclopropyl intermediate. As a result of an equiiibrium between the benzylium and tropylium ion configuratious, partial carbon atom scrambling occurs in the fused-ring structures. Fragmentation of these ions occurs only in the ring incorporating the methyl carbon. These conclusions are supported by MNDO calculations and by *3C-labeled methylphenanthrene and methylanthracene fragmentation studies.