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Ring contractions of dihydro- and tetrahydro-1,5-benzodiazepines in electron ionization mass spectrometry

✍ Scribed by Wen-Gang Chai; Guang-Hui Wang; Sheng Jin; Zu-Ming Lin; Ping Liu

Book ID: 102559054
Publisher: John Wiley and Sons
Year: 1987
Tongue: English
Weight: 273 KB
Volume: 22
Category: Article
ISSN: 1076-5174
DOI: 10.1002/oms.1210221004

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✦ Synopsis

Electron ionization mass spectra of a series of 2,4-disubstituted dihydro-and tetrahydro-1,5-benzodiazepines are discussed. The fragmentation of these compounds is dominated by ring contractions of diazepine, which give both five-and six-membered rings, benzimidazoles and quinoxalines. Tetrahydro compounds showed a tendency to eliminate one nitrogen from the ring system and give quinoline rings through NH, and NH4 eliminations. The electron ionization spectra of cis and trans isomers of tetrahydro compounds are identical.

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