ISSN:
0018-019X
Schlagwort(e):
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The aprotic decomposition of 5-amino-3, 4-dimethyl-isoxazole with excess isoamyl nitrite in aromatic solvents (alkylbenzenes, polyalkylbenzenes, anisole etc.) and in heteroaromatic solvents (thiophene, 2, 4-dimethylthiazole, pyridine, 4-alkylpyridines, dimethyl- and trimethyl-pyridines) leads to 5-aryl- and 5-heteroaryl-isoxazoles in yields of about 40%. This method provides a new way of obtaining 5-iodo-3, 4-dimethyl-isoxazole by the aprotic decomposition of the corresponding amine in the presence of iodine (yield: 30%).The relative reactivity of the 3,4-dimethylisoxazol-5-yl radical in alkyl benzenes, in anisole and in alkylpyridines is very similar to that of other heteroaromatic radicals with the radical site next to a sulfur or an oxygen atom. The radical shows electrophilic character because of the inductive effect of the oxygen atom. In the pyridine series an abnormally high percentage of 2-substitution occurs. This may be explained by a solvatation effect. The characteristic GLC., NMR. and MS. data are reported for most of the compounds studied.
Zusätzliches Material:
8 Tab.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/hlca.19760590531
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