ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
1,5-Dipolar Cyclizations, III. Condensed Triazoles from Conjugated Nitrilimines. Structure and Stability of the Products from the Reaction of N-Acylated Cyclic Amidrazones with Thionyl ChlorideSeveral examples of 1,5-dipolar cyclizations of conjugated nitrilimines are described. 2-(2-Acylhydrazino)pyridines 9 react with thionyl chloride to give 3-(2-pyridyl)-3H-1,2,3,4-oxathiadiazole-S-oxides 10, which are thermolyzed to s-triazolo[4,3-a]pyridines 11. Their structure is based on spectral data. l-(2-Acylhydrazino)isoquinolines 16 react with thionyl chloride to afford 2H-1,2,3,5-thiatriazolo[4,5-a]isoquinoline-S-oxides 17 or 3-(l-isoquinolyl)-3H-1,2,3,4-oxathiadiazole-S-oxide 18. Only the latter undergoes thermolysis with loss of SO2 and subsequent 1,5-dipolar cyclization to s-triazolo[3,4-a]isoquinolines 19. A crystal structure determination has confirmed the structure of 5-chloro-2-acetyl-2H-1,2,3,5-thiatriazolo[4,5-a]isoquinoline-S-oxide (17a).
Notes:
Beispiele 1.5-Dipolarer Cyclisierungen konjugierter Nitrilimine werden beschrieben. 2-[2-Acyl-hydrazino]-pyridine 9 reagieren mit. Thionylchlorid zu 3-[Pyridyl-(2)]-3H-1.2.3.4-oxathiadiazol-S-oxiden 10, deren. Thermolyse s-Triazolo[4.3-a]pyridine 11 liefert. Ihre. Strukturzuordnung basiert auf spektralen Daten. 1-[2-Acyl-hydrazino]-isochinoline 16 ergeben mit. Thionylchlorid 2H-1.2.3.5-Thiatriazolo[4.5-a]isochinolin-S-oxide 17 oder 3-[lsochinolyl-(l)]-3H-1.2.3.4-oxathiadiazol-S-oxid 18. Nur 18 unterliegt der Thermolyse unter SO2-Verlust mit anschließender 1.5-Dipolarer Cyclisierung zum s-Triazolo[3.4-a]isochinolin 19. Für 5-Chlor-2-acetyl-2H-1.2.3.5-thiatriazolo[4.5-a]isochinolin-S-oxid (17a) wird ein röntgenographischer Strukturbeweis geliefert.
Additional Material:
7 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19701030631
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