Syntheses of 1,3-Disilaindanes, 1,4-Disilatetralines, and 1,3-Disila-1,3-dihydroisobenzofuranes Using Cobalt-Catalyzed [2+2+2] Cycloadditions

Abstract

A simple catalytic system for [2+2+2] alkyne cycloadditions consisting of cobalt(II) iodide and zinc powder in acetonitrile was applied to the direct synthesis of hydroxyalkyl-substituted 1,3-disilaindanes, 1,4-disilatetralines, and 1,3-disila-1,3-dihydroisobenzofuranes starting from silicon-containing diynes and unprotected propargyl alcohols. Silicon-containing diynes were efficiently coupled with propargyl alcohols with a terminal or internal monoyne moiety. The method reported allows efficient, one-step syntheses of the title compounds.