ISSN:
0170-2041
Keywords:
Bicyclo[3.3.0]octanes
;
Tricyclo[4.2.1.03,7]nonanes
;
10-Azatricyclo[4.2.2.03,7]decanes
;
Titanium tetrachloride - methanol reagent
;
Vinyl sulfides, hydrocyanation of
;
α-Sulfinylnitriles
;
α-Cyano sulfoxides, thermolysis of
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Novel Tricyclic Products from Bis(arylthio)bicyclo[3.3.0]octadienes and Trimethylsilyl Cyanide in the Presence of Titanium Tetrachloride and Methanol.A four-step sequence converting ketones into α,β-unsaturated nitriles is put to test with the ketones 7 and 13. The tetramethylcyclohexanone 7 reacts with thiophenol or 4-chlorothiophenol in the presence of titanium tetrachloride and triethylamine to afford the phenyl vinyl sulphides 8. Treatment of 8 with a reagent, obtained from titanium tetrachloride and methanol, subsequent with trimethylsilyl cyanide produces the α-phenylthionitriles 9 in moderate yields. Oxidation of 9a with 3-chloroperbenzoic acid yields the α-phenylsulphinylnitrile 12 which decomposes at temperatures as low as 100°C to furnish a quantitative yield of the unsaturated nitrile 11. - When the mixture of bifunctional vinyl sulphides C2-, CS-14a is allowed to react at -30°C with titanium tetrachloride/methanol and, subsequently, with trimethylsilyl cyanide, a mixture of the bicyclic α-(phenylthio)nitriles exo-15 and 16 and of the tricyclic products 17 and 18 is obtained. This mixture is separated by chromatography. At 20-25°C, the otherwise identical procedure furnishes an isomer of 17, viz. the tricyclic piperidine 21a which is derived from a novel heterocyclic system. The gross structures are based on spectroscopic evidence. The configurations of 16, 17, and 21b, and the structure of 18 as well, are established by X-ray diffraction analyses. The mechanisms of the unexpected cyclization reactions leading to the tricyclic products 17, 18, and 21 are discussed.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1992199201126
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