Mass Spectra of New Heterocycles: XXI. Study of Alkyl [(5-Amino-1H-pyrrol-2-yl)sulfanyl]acetates by Electron and Chemical Ionization Mass Spectrometry

• Published in: Russian journal of organic chemistry Vol. 56; no. 5; pp. 768 - 774
• Main Authors: Klyba, L. V., Nedolya, N. A., Sanzheeva, E. R., Tarasova, O. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-05-2020; Springer Nature B.V
• Subjects: Acetates; Chemistry; Chemistry and Materials Science; Electrons; Fragmentation; Ionization; Ions; Mass spectra; Mass spectrometry; Molecular ions; Organic Chemistry; Protonation; alkyl [(5-amino-1; mass spectra; molecular ion; pyrrol-2-yl)sulfanyl]acetates; electron and chemical ionization; fragmentation
• ISSN: 1070-4280; 1608-3393
• DOI: 10.1134/S1070428020050073

The fragmentation of previously inaccessible alkyl [(5-amino-1
H
-pyrrol-2-yl)sulfanyl]acetates under electron (70 eV) and chemical (reactant gas methane) ionization conditions was studied for the first time. Under electron ionization, all the studied compounds form a molecular ion (
I
rel
7–100%), the main primary fragmentation pathway of which is associated with the C–S bond cleavage in the sulfanyl group and elimination of the ester fragment (R
4
OCOCH
2
) in the form of a radical. The chemical ionization of alkyl [(5-amino-1
H
-pyrrol-2-yl)sulfanyl]acetates is characterized by protonation, recharging, and electrophilic addition. The base peak belongs to an [
M
+ H]
+
ion. Chemical ionization is accompanied by the elimination of an R
4
OCOCH
2
radical from the
M
+•
and [
M
+ Et]
+
ions and an R
4
OCOCHS molecule from the
M
+•
and [
M
+ H]
+
ions.