Synthesis of Para (−)-Δ8-THC Triflate as a Building Block for the Preparation of THC Derivatives Bearing Different Side Chains

A two-step synthesis of para (−)-Δ 8 -THC-OTf that can be used as building block for late-stage introduction of side chains to the tetrahydrodibenzopyran core of THC by cross-coupling chemistry is presented. No protecting groups are needed, and (−)-Δ 8 -THC-OTf can be cross-coupled to access derivatives bearing pharmacologically interesting side chains such as benzoyl units, sterically demanding groups, aromatic chains, and alkenyl groups. This approach allowed an efficient four-step synthesis of (−)-Δ 8 -THC from commercial materials.