HETEROCYCLIZATIONS INDUCED BY THALLIUM(III) ACETATE - EFFECT OF VARYING THE INTERNAL NUCLEOPHILE

The stereochemistry of the 2,5-disubstituted tetrahydrofuran formed on treating 5-methyl-1-phenylhex-4-en-1-ol [6] with thallium(III) acetate in appropriate solvents has been established as trans by means of nuclear Overhauser experiments. Replacement of the hydroxy group of [6] by ether, ester, amide or carbamate functionalities suppresses intramolecular nucleophilic participation during oxythallation. Instead, products of acetoxythallation followed by solvolysis of the C-Tl bond or by methyl group migration are isolated. © 1990.