Draft:Conversion of CBD to THC

Cannabidiol (CBD) can be chemically converted into tetrahydrocannabinol (THC) via a ring-closing reaction. This cyclization can be acid-catalyzed or brought about by heating.

Known methods

At least different three methods, that are independent of each other, have been utilized to convert CBD to THC.

• Despite the CBD and THC having the same molecular weight, multiple analytical methods are able to differentiate them.

• "on the recovery of both THC (86.7−90.0%) and CBD (92.3−95.6%). The slightly lower recovery of THC can be explained by the fact that THC is less polar than CBD and more likely to remain in the nonpolar sunflower oil."

By heat

CBD heated to 175, or 250–300 °C may partially be converted into THC.

• Heat is required to decarboxylate THCA to psychoactive cannabinoid THC. Likewise, CBDA turns into CBD.

• From hemp plant material in an oven, cannabinoid concentration plots (time/temp) show THC:

• STP 0 minutes 0.20mg/g
• 140-160C 20 minutes 0.27mg/g
• 140-160C 60 minutes 0.05-0.15mg/g
• 120C 45 minutes 0.27mg/g
• 120C 90 minutes 0.20mg/g
• 100C 90 minutes 0.25mg/g
• 80C 120 minutes 0.24mg/g

Multiple oxidation products begin to form with degradation (the loss is greatly reduced in the absence of oxygen).

• "the boiling point for THC has been determined at 157 °C, and the boiling point range for CBD sits between 160 and 180 °C."

With acid

Mechanism of the acid catalyzed conversion of CBD into THC

CBD converts to various isomers of THC with catalysts in acidic environments.

• add protons until the CBD sterically-hindered alcohol functional group becomes the ether heterocyclic hexane in THC re:Figure 4.(b)

• Basically everything about how to do it with Lewis acids - a continuous rather than batch implementation with similar materials

• Basically how to do it with a catalytic acid solution in 5 minutes in a microwave with a 40% d9 and 35% d8 yield

With zeolite

"Zeolites selected from the group consisting of analcime, chabazite, clinoptilolite, erionite, mordenite, phillipsite, and ferrierite."

In vivo

There is a debated hypothesis that oral CBD is converted into THC under acidic conditions in the stomach and then absorbed into the blood stream. However, neither THC nor any of its active metabolites have been detected in blood in animals or humans after ingesting CBD. There is no direct evidence of the conversion of CBD to THC in the human gut; both CBD and THC are excreted unchanged within feces.

"An important consideration for the cannabinoid analysis is that cannabinoids from plants are effectively in a “prodrug” form, existing as cannabinolic acids that must be decarboxylated to their respective cannabinol form to have pharmacological effects.2 This decarboxylation, for example, occurs while smoking; however, upon oral consumption, no CBDA or THCA present is converted to CBD or THC by enzymatic or other processes.37,38 If the production and processing of CBD oils does not remove all THCA and CBDA, some THCA and CBDA might still be present in the final CBD oil products."