Brønsted Acid?Catalyzed Enantioselective Iodocycloetherification Enabled by Triphenylphosphine Selenide Cocatalysis

Enantioselective iodocycloetherifications can be conducted using sterically highly demanding BINOL-based phosphoric acid diesters as catalyst. To achieve enantioselective reactions, cocatalysis by triphenylphosphine selenide is necessary. With cocatalysis, good to excellent enantioselectivities achieved for a broad range of substrates catalyst and cocatalyst loadings low 1 mol %. The itself does not strongly influence diastereoselectivity, but leads higher reactivity and, in combination with diester, enantioselectivity.