Patent ID: 8383842

Claim:
A method for preparing a trans-(−)-Δ 9 -tetrahydrocannabinol composition, comprising: allowing a composition comprising (±)-Δ 9 -tetrahydrocannabinol to separate on a chiral stationary phase in the presence of an eluting solvent to provide a trans-(−)-Δ 9 -tetrahydrocannabinol composition; wherein the (±)-Δ 9 -tetrahydrocannabinol is obtained from crystalline (±)-Δ 9 -tetrahydrocannabinol, and wherein the crystalline (±)-Δ 9 -tetrahydrocannabinol is obtained by allowing trans-(−)-Δ 9 -tetrahydrocannabinol and trans-(+)-Δ 9 -tetrahydrocannabinol to crystallize from a first composition comprising trans-(−)-Δ 9 -tetrahydrocannabinol, trans-(+)-Δ 9 -tetrahydrocannabinol, and a non-polar organic solvent to provide crystalline (±)-Δ 9 -tetrahydrocannabinol, wherein the first composition is obtained by: (a) forming a biphasic composition comprising (i) a first organic phase, and (ii) an alcoholic-caustic phase containing the trans-(−)-Δ 9 -tetrahydrocannabinol, the trans-(+)-Δ 9 -tetrahydrocannabinol, or the trans-(−)-Δ 9 -tetrahydrocannabinol and trans-(+)-Δ 9 -tetrahydrocannabinol; (b) separating the trans-(−)-Δ 9 -tetrahydrocannabinol, the trans-(+)-Δ 9 -tetrahydrocannabinol, or the trans-(−)-Δ 9 -tetrahydrocannabinol and trans-(+)-Δ 9 -tetrahydrocannabinol from the alcoholic-caustic phase; and (c) forming a first composition comprising the trans-(+)-Δ 9 -tetrahydrocannabinol, trans-(−)-Δ 9 -tetrahydrocannabinol, and a non-polar organic solvent.