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Linear dependence of the intensity of the [M + H]+ ion peak in fast atom bombardment mass spectrometry on the basicity of meso-substituted octaethylporphyrins

✍ Scribed by Lin Van; Yi-Wei Fang; Xi-Yun Liang; Guo-Zhang Wu; Hiu-Kwong Leung

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
308 KB
Volume
26
Category
Article
ISSN
1076-5174

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✦ Synopsis

A fast atom bombardment mass spectrometric study of the meso-substituent effect of octaethylporphyrins (QEPX, X = NH, , CH, , H, CHQ, C1, CN, NO,) is reported. The intensity of the [ M + H] + ion peaks was estimated quantitatively using an external standard, which was observed to be correlated linearly with the basicity (pK,) of the QEPX. The pK, value of the OEPXs was obtained by titration with perchloric acid and it was observed to be correlated linearly with Hammett's up value, with a p value of 1.38.

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