Fragmentation of 1-alkyl derivatives of 5- and 7-nitro-2,1-benzisothiazoline 2,2-dioxides upon electron ionization

Eur. J. Mass Spectrom. 3, 55–65 (1997)
DOI: 10.1255/ejms.3

Fragmentation of 1-alkyl derivatives of 5- and 7-nitro-2,1-benzisothiazoline 2,2-dioxides upon electron ionization

Witold Danikiewicz^* and Krzysztof Wojciechowski
Institute of Organic Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw, Poland.

ABSTRACT:

Fragmentation patterns upon electron ionization of some 1-alkyl-5-nitro- and 1-alkyl-7-nitro-2,1-benzisothiazoline 2,2-dioxides are described. It is observed that the molecular ions of the 7-nitro isomers undergo rearrangement reactions resulting in the loss of a molecule of the appropriate carbonyl compound and, concurrently, an acyl radical. Mechanisms for these reactions, which can be assumed to be an example of the "ortho-effect", are proposed.

Keywords: EI fragmentation mechanisms, ortho-effect,2,1- benzisothiazoline 2,2-dioxide derivatives.

You can buy this paper on-line in PDF format; it costs only £11.75. Just click on the BUY on-line button. You can pay on-line through a secure server and get access immediately.