|
Eur. J. Mass Spectrom. 1, 457 - 463 (1995) |
|
Gas-phase methylation of the 2-hydroxypyridine/2-pyridone system by the dimethylchlorinium ion | ||
Richard A.J. O'Hair,* Michael A. Freitas, Joseph A.R. Schmidt and Mark E. Hatley |
||
ABSTRACT: | ||
The gas-phase reactions of 2-methoxypyridine, 1-methyl-2-pyridone and the tautomeric 2-hydroxypyridine/2-pyridone system with the dimethylchlorinium ion have been investigated in the CI source of a tandem mass spectrometer. The mechanisms of these reactions were determined by analyzing the unimolecular fragmentation reactions of the product ions, which were compared, where possible, with the fragmentation reactions of the independently synthesized postulated products. (CH3)2Cl+ methylates both 2-methoxypyridine and the 2-hydroxypyridine tautomer at nitrogen, while methylating 1-methyl-2-pyridone and the 2-pyridone tautomer at oxygen. These results are consistent with the ab initio calculated (at the MP2(FC)/6-31G"//HF/6-31G" level) relative stabilities of various isomeric [M + CH3]+ ions of 2-hydroxypyridine and 2-pyridone. Comparisons with solution reactivity are made. | ||
Keywords: |
You can now 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.
© IM Publications
Any problems? E-mail .