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Electron impact ionization mass spectrometry and intramolecular cyclization in 2-substituted pyrimidin-4(3H)-ones

✍ Scribed by Pentti Oksman; Géza Stájer; Kalevi Pihlaja; Mati Karelson

Book ID: 103995856
Publisher: Elsevier Science
Year: 1994
Tongue: English
Weight: 627 KB
Volume: 5
Category: Article
ISSN: 1044-0305
DOI: 10.1016/1044-0305(94)85043-7

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✦ Synopsis

Electron impact ionization mass spectrometry indicates that the behavior of W-unsubstituted pyrirnidin-4-ones with CH2-R type substitution at C-2 differs from homologs that are N-substituted and/or 2-aryl- or 2-methyl-substituted. A dominant intramolecular cycliza-tion was found to occur between 3ZV (in agreement with the predominance of the 3NH tautomers) and the ortho positions of the aryl moiety in compounds with a CH2-aryl substitution at C-2. Theoretical calculations with an AMI SCFR method on 2-, 6-, and 2, 6-disubstituted pyrimidin-4-ones support the mass spectrometric observations.

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