Allyloxy and 2-propargyloxy alkyl tellurides as precursors of tetrahydrofuran derivatives

7 2-Allyloxy and 2-propargyloxy alkyl tellurides as precursors of tetrahydrofuran derivatives 

The allyloxy and propargyloxy compounds are easily prepared by the opening of mono-substituted epoxides with sodium aryl tellurolates, followed by allylation and propargyla-tion of the obtained -hydroxytellurides, submitted to irradiation with a sun lamp in the presence of hexabutylditin, and suffer group-transfer cyclization under 5-exo-mode to give the 2,4-disubstituted tetrahydrofuran derivatives.  

Typical procedure for group-transfer radical cyclization preparation of compound 3bP (Ar = p-CF3CgH4) To a solution of 2-(allyloxy)cyclohexyl 4-(trifluoromethyl)phenyl 

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