Enantioselective Catalyzed Addition of Substituted Indens to Unsaturated Epoxides

Unsaturated aromatic epoxides can be regioselectively opened by substituted indenes in the presence of catalytic amounts of (R)-1,1'-bi-2,2'-naphthotitanium diisopropoxide (1 mol%). The reaction proceeds and enables the synthesis of (1R,2R)-2-(5-bromo-1H-inden-3-yl)-2-phenyl-1-[(prop-2-yn-1-yl)oxy]propan-1-ol with moderate yield and high enantioselectivity (ee up to 97%).