Improved accessibility to the desoxy analogues of Δ9-tetrahydrocannabinol and cannabidiol

Desoxy analogues of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) have been reported to provide a novel mode of analgesia whilst avoiding the psychotropic side effects associated with most cannabinoid drugs. A detailed and improved synthesis of desoxy THC, desoxy CBD and didesoxy CBD is reported here. The key improvements include a concentration-dependent boron trifluoride mediated electrophilic aromatic substitution which was used to synthesize both THC and CBD analogues. The synthetic route is general and could be applied to the development of a library of modified desoxy THC and desoxy CBD analogues.