Thermal isomerization of the isoxazole ring and rearrangement processes in the mass spectra of 3-aryl-5-methylisoxazole-4-carboxylic acids
- 45 Downloads
The mass spectra of 15 compounds of 3-aryl-5-methylisoxazole-4-carboxylic acid and their derivatives were investigated. Thermal isomerization of the isoxazole ring was observed for several derivatives of this series. The formation of rearranged pseudomolecular ions of the arylamines during the dissociative ionization of 3-aryl-5-methylisoxazole-4-carboxylic acids was examined on the basis of a study of the mass spectra of labeled compounds. It is assumed that there is a high probability of concerted elimination of several groups in the first step of the disintegration of the molecular ion.
KeywordsMass Spectrum Organic Chemistry High Probability Isoxazole Arylamines
Unable to display preview. Download preview PDF.
- 1.K. K. Zhigulev, R. A. Khmel'nitskii, M. A. Panina, I. I. Grandberg, and B. M. Zolotarev, Khim. Geterotsikl. Soedin., 889 (1972).Google Scholar
- 2.M. Ohashi, H. Kamachi, H. Kakisawa, A. Tatematsu, H. Yoshirimi, H. Kano, and H. Nakata, Org. Mass Spectrometry,2, 195 (1969).Google Scholar
- 3.T. Nishiwaki, Tetrahedron Lett., 2049 (1969).Google Scholar
- 4.T. Nishiwaki, Chem. Commun., 945 (1970).Google Scholar