Conversion of CBD to Δ
View Patent ↗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 cannabidiol (CBD) to Δ 9 -tetrahydrocannabinol (Δ 9 -THC) comprising:
providing a reaction mixture comprising CBD in dry methylene chloride;
adding BF 3 Et 2 O to the reaction mixture;
stirring the ice cold reaction mixture under a nitrogen atmosphere;
adding NaHCO 3 to the reaction mixture;
allowing the mixture to separate into an aqueous phase and an organic phase;
removing the organic phase;
washing the organic layer with water; and
eluting Δ 9 -THC from the organic phase, purity of the eluted Δ 9 -THC being greater than 97%.
2. The method according to claim 1 including stirring the reaction mixture for approximately 1 hour.
3. The method according to claim 1 including drying the organic phase over MgSO 4 and evaporating the organic phase following washing.
4. The method according to claim 1 including eluting the organic phase on an HPLC column.
5. The method according to claim 4 wherein the Δ 9 -THC is eluted with ether in petroleum ether following washing the column with petroleum ether.
6. The method according to claim 5 wherein the ether in petroleum ether is 2 parts ether in 98 parts petroleum ether.
7. The method according to claim 1 including eluting the organic phase on an RP-HPLC column.