Stereoselective(3 + 3)-Cycloannulation of CarbonylYlides and (<i>Z</i>)‑3-Benzylidene‑3<i>H</i>‑indoles Enabled by Cooperative Rh/Chiral PhosphoricAcid Catalysis

A diastereo- and enantioselective (3 + 3)-cycloannulation of in situ generated carbonyl ylides and (<i>Z</i>)-3-benzylidene-3<i>H</i>-indoles enabled by cooperative Rh/chiral phosphoric acid catalysis is reported. This study is the first to describe an enantioselective synthesis of cyclohepta[<i>b</i>]indole with an oxa-bridged motif. The scope of the reaction is broad, and the oxa-bridged cyclohepta[<i>b</i>]indole products were obtained in moderate to good yields and with excellent diastereoselectivities and good to high enantioselectivities.