Diastereo‐ and Enantioselective Synthesis of Tetracyclic Cycloheptanols through (4+3) Annulation via C−C/C−H Activation Cascade

Abstract

AbstractTransition metal‐catalyzed annulations of four‐membered rings via C−C activation are powerful tools to construct complex fused and bridged ring systems. Despite significant progress in (4+1), (4+2) and (4+4) annulations, the (4+3) annulation remains unexplored. Herein, we develop an asymmetric Rh‐catalyzed intramolecular (4+3) annulation of α‐arylalkene‐tethered benzocyclobutenols for the synthesis of dihydrofuran‐annulated dibenzocycloheptanols with two discontinuous chiral carbon centers via a C−C and C−H activation cascade. The reaction features excellent diastereo‐ and enantioselectivities and 100 % atom economy, and is applicable to late‐stage modification of complex molecules.