Absolute Assignment of Constitutional Isomers via Structurally Diagnostic Fragment Ions: The Challenging Case of alpha- and beta-Acyl Naphthalenes

作者：Benassi Mario; Eberlin Marcos N^*

来源：Journal of the American Society for Mass Spectrometry, 2010, 21(12): 2041-2050.

DOI：10.1016/j.jasms.2010.08.019

A general mass spectrometric method is described for the absolute assignment of alpha- or beta-acyl naphthalenes, via which the gaseous alpha- and beta-naphthoyl cations of m/z 155 are used as structurally diagnostic fragment ions (SDP) These stable acylium ions are common and normally abundant fragment ions of acylnaphthalenes in general Using a pentaquadrupole mass spectrometer, CID experiments with argon and ion/molecule reactions with 2-methyl-1,3-dioxolane, isoprene, acetonitrile and propionitrile were performed but failed to distinguish the two SDF1 Reactions with ethyl vinyl ether and several homologues as well as ethyl vinyl thioether were, however, successful In reactions with ethyl vinyl ether, the alpha-SDFI form a pair of diagnostic product ions of m/z 165 and m/z 181, which are absent in the corresponding spectrum of the beta-SDFI Methyl 4-(1-naphthyl)-2,4-dioxobutanoate was used as a test molecule for this class of constitutional isomers and absolute structura

• 出版日期2010-12