CONVERSION OF CBD TO DELTA8-THC AND DELTA9-THC
Methods of converting cannabidiol to Δ 8 -tetrahydrocannabinol or Δ 9 -tetrahydrocannabinol are described. The described methods produce higher yields and higher purity compared to prior art methods.
1 . A method of converting CBD to Δ 8 -THC comprising:
providing a reaction mixture comprising a Lewis acid in an organic solvent;
adding CBD to the reaction mixture;
refluxing said reaction mixture;
diluting the mixture with an organic solvent;
pouring the mixture into cold water;
mixing the mixture;
allowing the mixture to separate into an aqueous phase and an organic phase;
removing the organic phase; and
eluting Δ 8 -THC from the organic phase.
2 . The method according to claim 1 wherein the reaction mixture is mixed under a nitrogen atmosphere.
3 . The method according to claim 1 wherein the Lewis acid is p-toluenesulfonic acid in toluene.
4 . The method according to claim 1 wherein the Lewis acid is boron trifluoride.
5 . The method according to claim 1 wherein the Δ 8 -THC is eluted by HPLC.
6 . The method according to claim 1 wherein the Δ 8 -THC is eluted by RP-HPLC.
7 . The method according to claim 1 including washing the organic phase with aqueous NaHCO 3 prior to eluting.
8 . The method according to claim 7 including drying the organic phase over MgSO 4 and evaporating the organic phase following washing.
9 . The method according to claim 5 wherein the Δ 8 -THC is eluted with ether in petroleum ether.
10 . The method according to claim 9 wherein the ether in petroleum ether is 5-10% ether in petroleum ether.
11 . The method according to claim 6 wherein the Δ 8 -THC is eluted with water-methanol or water-acetonitrile.