Rh-Catalyzed Synthesis of Helically Chiral and Ladder-Type Molecules via [2 + 2 + 2] and Formal [2 + 1 + 2 + 1] Cycloadditions Involving C−C Triple Bond Cleavage

We have developed highly enantioselective synthesis of functionalized helically chiral molecules via a Rh-catalyzed [2 + 2 + 2] cycloaddition and synthesis of ladder-type molecules via an unprecedented Rh-catalyzed formal [2 + 1 + 2 + 1] cycloaddition involving C−C triple bond cleavage.