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cbd to thc conversion

Cbd to thc conversion

The acid-catalyzed conversion of CBD has been studied since the early 1940s, when Adams et al. [74] reported on the treatment of CBD with various acids. While adding trichloroacetic acid, anhydrous oxalic acid, picric acid, 3,5-dinitrobenzoic acid, 87% formic acid, glacial acetic acid and malic acid to a solution of CBD in benzene did not result in conversion even after boiling for 10–20 h, good results were achieved with the addition of dilute ethanolic hydrochloric acid, p-toluenesulfonic acid or a drop of sulfuric acid (100%) in cyclohexane. The conversion product was described to be a psychotropic cannabinoid, which the authors assumed to be either Δ 9 -THC or Δ 8 -THC ( Figure 4 ). This observation was later confirmed by Gaoni and Mechoulam [55], who described the correct structures of CBD, Δ 9 -THC and Δ 8 -THC based on careful spectroscopic studies (i.e., UV, IR and NMR measurements). They were further able to verify the hypothesis of Adams et al. [75] that Δ 9 -THC was the main product if CBD was subjected to treatment with hydrochloric acid. The addition of p-toluenesulfonic acid, though, rather resulted in the formation of Δ 8 -THC.

Despite the various problems arising from analytical challenges in the field of cannabis research, only 2% of all publications on cannabis deal with analytics, as stated by Gertsch et al. [73] in the editorial of a recently published special issue on cannabis. Hence, when comparing results of in vitro (Section 3.2.3) or in vivo (Section 3.2.4) studies on the conversion of CBD, analytical challenges need to be considered and all claims should be critically assessed.

Fourteen years later, the studies were continued by Watanabe et al. [39], who found that CBD was converted to 9α-hydroxy-HHC, 8-hydroxy-iso-HHC, Δ 9 -THC and CBN when subjected with artificial gastric juice (without pepsin) and incubated at 37 °C for 20 h. The analysis of the ethyl acetate extracts was carried out by GC/MS and structures were assigned by mass spectral data and retention times as compared to the self-synthesized (or isolated) reference standards (Δ 9 -THC, CBD, CBN, 8-hydroxy-iso-HHC and 9α-hydroxy-HHC).

3.2.3. In Vitro Studies: Conversion of CBD in Artificial Gastric Juice and Other Model Systems

Besides Δ 9 -THC, the non-psychotropic cannabidiol (CBD, Figure 1 c) gained increasing popularity due to a broad spectrum of health-promoting effects ascribed to it with several reviews on safety and efficacy available [7,8,9,10,11,12,13,14,15,16,17,18]. In recent years, this culminated in extensive consumer interest with heavily increasing numbers starting in 2018 ( Figure 2 ). Since then, so-called CBD extracts used as a food constituent, in cosmetic products or in the liquids for electronic cigarettes are found with a large variety in drug stores or in online shops [19,20,21]. According to the Novel Food Regulation (EU) 2015/2283, an approval of CBD extracts for the use in food requires a history of food consumption prior to May 1997 [3,22]. Thus, as such a history has not been demonstrated so far, CBD extracts are classified as Novel Food and are therefore not authorized in the EU.

In contrast to that, the acid forms Δ 8 -tetrahydrocannabinolic acid (Δ 8 -THCA) and Δ 9 -THCA as well as the metabolite 11-COOH-THC failed to cause any observable physiological effect or psychotropic effect, even though detailed studies are missing [40]. However, as mentioned by Moreno-Sanz et al. [41], Δ 9 -THCA slowly decarboxylates to form THC during storage and fermentation but also during the baking of edibles, smoking or vaporizing and may thus exhibit psychotropic effects upon respective consumption.

3.2.2. Conversion of CBD under Acidic Conditions

In an excellent review about the chemistry, synthesis and bioactivity of CBC, Pollastro et al. [52] summarized recent studies on the psychotropicity of CBC. Even though no narcotic effect was found in in vivo experiments, high doses of CBC may indeed exhibit responses typical for Δ 9 -THC (e.g., hypomotility, catalepsy, hypothermia and analgesia). The authors claim that the reason for this effect most likely derives from another than the typical mechanism, as CBC was found to show only marginal affinity for the cannabinoid receptors CB1 and CB2 [52]. Besides that, multiple other effects are related to CBC, among which the antibacterial and antifungal activity is the most noteworthy one as CBC outperforms other cannabinoids in this category. According to the authors, little information exists regarding the biological profile of naturally occurring analogs of CBC [52].

Some general observations were reported by Compton et al. [44], who investigated the correlation of binding affinity with psychotropic effects in humans for various different cannabinoids in a detailed study and found a strong correlation. Interestingly, this study revealed that cannabinoids with long (branched) side chains at C3 do have larger binding affinities compared with ones with short (unbranched) side chains. Besides that, hydroxy groups or halogens located at the terminal end of the side chain (i.e., at C5′ position) induced good binding affinities. Carboxylic acid metabolites of either Δ 9 -THC or Δ 8 -THC, though, were not found to bind to the receptor at all. This is well in agreement with findings of their non-psychotropic effects. The authors additionally reported on different binding characteristics for CBD and Δ 9 -THC and used this as a hypothesis for their different physiological effects [44].

Cbd to thc conversion

Once you’ve selected your acid, mix it into the CBD and solvent mixture (amount varies, but usually around 10%). Now you’ll need to leave the mixture on a stirring plate. Some recipes call for using room temperature; others add heat. Either way, it’s going to stay here for the next 3–18 hours.

Similar methods can be used to convert CBD into delta 9 and delta 10 THC (Δ10 THC) as well.

Step 4: Remove the Solvent

The reaction is a cyclization (addition) reaction to the terminal alkene (H2C=) coming off the CBD molecule from the adjacent O-H group on the phenyl ring [2].

It’s important to test a sample after the fourth wash to make sure there are no detectable levels of the acid. If there is, keep repeating the washing process until it’s no longer detected.

Table of Contents

Depending on the process and chemicals used, different ratios of delta 8, delta 9, or delta 10 THC will form.