The Hydroboration-Iodination of Dialkylselenoacetylenes to Vinylic Diselenides

Article abstract of DOI:10.1055/s-1997-959

The hydroboration of dialkylselenoacetylenes 1, generated from alkylseleno bromides and sodium acetylide in liquid ammonia, with dicycloalkylboranes followed by iodination under basic condition produced (Z)/(E)-vinylic diselenides (2/3). The reaction proceeds with a transfer of one cycloalkyl group and smoothly to give major 2 and minor 3 in almost quantitative ratio (2:3=93:7 to 97:3). The hydroboration-iodination process provides a general method for synthesis of (Z)-vinylic diselenides containing cyclic systems.