Selective ion-molecule reactions of 2,5-dimethylpyrrole-γ-butyrolactone with dimethyl ether ions

Abstract

The llpe of bimolecuhr reactions as selective and sensitive diagnostic probes of analytically relevant molcules has undergone rapid development, especiPlly with tbe increasing availability of ion trapping techniques which allow detailed exsmiacrtioa of ion-molecule reactions. In this report, selective ion-molecule reactions of 2 , s dimethylpyrrole-y-butyrolacto~ with protoaated dimethyl ether and methoxymethylene cations (CH,OCH, +) are described. A qwdrupole ion trap and a triplequadrupole mass spectrometer are used to examine the bimolecular and dmiation reactions of y-butyrolactone and 2,5dimethylpyrrole, both of which are the building blocks of a more complex bicyclic substrate, 2,5-dimethylpyrrole-y-butyrolactone. All three compounds are protonated by ionmolecule reactions with dimethyl ether ions. The y-butyrolactoue also reacts with CH30CHz+ to produce

Differentiation of Regioisomeric Aromatic Ketocarboxylic Acids by Positive Mode Atmospheric Pressure Chemical Ionization Collision-Activated Dissociation Tandem Mass Spectrometry in a Linear Quadrupole Ion Trap Mass Spectrometer

“…CAD-based MS n techniques have been applied to the characterization of unknown substances in many fields, including the pharmaceutical industry [19,20], and research on chemical warfare agents [21], proteins [22], volatile organic compounds [23], airborne oxidants [24], bacteria, DNA [25,26], and microextracted water samples [27]. Hydrogen/deuterium (H/D) exchange experiments [28][29][30] and molecular orbital calculations [31,32] have facilitated the differentiation of isomeric compounds.…”

Localization of ferruginol, a diterpene phenol, in Cryptomeria japonica heartwood by time-of-flight secondary ion mass spectrometry

“…In addition to sodium ion, chloride ion, silver ion or silicon ion participate in the formation of adduct ion in TOF-SIMS. Many papers (Donovan and Brodbelt 1992;Iida et al 1993;Wu et al 2001) have reported that adduct ions such as [M+13] + ion and [M+15] + ion, which are considered to be formed by methylene substitution and methyl-cation attachment, respectively, are generated in chemical ionization mass spectrometry such as electron spray ionization mass spectrometry. The m/z 301 ion generated from ferruginol by TOF-SIMS corresponds to [M+15] + ion, and is considered to be an adduct ion formed by methyl-cation attachment.…”

Observation of self‐ion–molecule reactions during collisionally activated dissociation in an ion‐trap mass spectrometer

“…SIMR leading to the formation of methyne addition reactions in an ITMS has been investigated previously 6–9. Brodbelt and co‐workers examined methyne addition reactions by dimethyl ether (DME) CI for many compounds using an ITMS 10–26. The purpose of this paper is to describe the phenomenon when CAD is performed on the methyne adduct ions produced from both SIMR or CI, using both external and internal source ITMS instruments, where the SIMR can occur and lead to the formation of the protonated molecules or adduct ions.…”