Hexyne 6-cyclohexyl

Whereas a number of 5-aryl thiatriazoles have been reported, the only previously known true aliphatic and alicyclic representatives were 5-tert-butyl31 and cyclohexyl thiatriazole.32 These are unstable oils that decompose at 0° with nitrogen evolution and formation of sulfur. They are prepared from the corresponding thioacylhydrazides and nitrous acid, but the method is not generally applicable because of difficulties in obtaining the required aliphatic thioacylhydrazides.1 Wijers et o/.17 have found that aliphatic thiatriazoles can be prepared from 1-acetylthio-l-alkynes. Thus a substance believed to be 5-pentylthiatriazole was isolated from the reaction between 1-acetylthio-l-hexyne and ammonium azide. It is an oil that solidifies at about —16° and could not be analyzed because of its explosive character and poor stability at room temperature. Its formation is explained by the following scheme [Eq. 

This sequence can be repeated several times, and Bourguel20 converted 3-cyclo-hexyl- 1-propyne into 6-cyclohexyl-1-hexyne by three-fold chain extension in this way. The following are details for the penultimate rearrangement step ... 

A soln. of borane in tetrahydrofuran added dropwise to an ice-cooled soln. of cyclohexene in the same solvent, stirred 1 hr. at 0-5°, treated at 15-20° with 1-hexyne in tetrahydrofuran, the resulting soln. stirred 0.5 hr. at room temp., 6 N NaOH added at -10° followed by dropwise addition during 15 min. of a soln. of iodine in tetrahydrofuran, and allowed to warm to room temp. cis-1-cyclohexyl-1-hexene. Y 75%. G. Zweifel, H. Arzoumanian, and G. G. Whitney, Am. Soc. 89, 3652 (1967). 

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