Access to Hexahydroindeno[2,1-c]pyran-Based Propellanes by a Domino Prins/Friedel-Crafts Cyclization

Starting from readily available cyclic homoallylic alcohols, a Prins reaction allowed the formation of a bicyclic tetrahydropyranyl carbocation intermediate that is only trapped by electron-rich aromatic rings according a further intramolecular Friedel-Crafts reaction leading to new [4.4.3]propellane structures.

Automated summary

A Prins reaction followed by intramolecular Friedel-Crafts reaction was used to synthesize novel [4.4.3]propellane structures from readily available cyclic homoallylic alcohols.