Characterization of the C3H6O+·ion from 2-methoxyethanol. Mixture analysis by dissociation and neutralization—reionization

✍ Scribed by Michael J. Polce; Chrys Wesdemiotis

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 601 KB
• Volume: 6
• Category: Article
• ISSN: 1044-0305
• DOI: 10.1016/1044-0305(95)00504-8

✦ Synopsis

The C3H60 ~" ion formed upon the dissociative ionization of 2-methoxyethanol is identified by a combination of several tandem mass spectrometry methods, including metastable ion (MI) characteristics, collisionally activated dissociation (CAD), and neutralization-reionization mass spectrometry (NRMS). The experimental data conclusively show that 2methoxyethanol molecular ion, namely, HOCH2CH2OCH;; loses H20 to yield mainly the distonic radical ion .CH2CHaOCH; along with a smaller amount of ionized methyl vinyl ether, namely, CH2~--~-CHOCH~'. Ring-closed products, such as the oxetane or the propylene oxide ion are not observed. The proportion of • CH2CH2OCH + increases with decreasing internal energy of the 2-methoxyethanol ion, which indicates a lower critical energy for the pathway leading to this product than for the competitive generation of CH2=CHOCH~'. The present study also uses MI, CAD, and NRMS data to assess the structure of the distonic ion +(CH3)CHOCH 2 -(ring-opened ionized propylene oxide) and evaluate its isomerization proclivity toward the methyl vinyl ether ion.