THC-O-acetate (THC acetate ester, O-acetyl-THC, THC-O, AcO-THC) is the
acetate
An acetate is a salt formed by the combination of acetic acid with a base (e.g. alkaline, earthy, metallic, nonmetallic, or radical base). "Acetate" also describes the conjugate base or ion (specifically, the negatively charged ion called ...
ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...
of
THC. The term ''THC-O-acetate'' and its variations are commonly used for two types of the substance, dependent on which cannabinoid it is synthesized from. The difference between Δ
8-THC and Δ
9-THC is the location of the double bond within the
cyclohexene
Cyclohexene is a hydrocarbon with the formula . It is a cycloalkene. At room temperature, cyclohexene is a colorless liquid with a sharp odor. Among its uses, it is an chemical intermediate, intermediate in the commercial synthesis of nylon.
Prod ...
ring system.
Physical data, chemistry, and properties
THC acetate ester (THC-O or THCOA) can be synthesized from
THC,
or from
THCA.
The acetylation of THC does not change the properties of the compound to the same extent as with other acetate esters, as the parent compound (THC) is already highly
lipophilic
Lipophilicity (from Greek language, Greek λίπος "fat" and :wikt:φίλος, φίλος "friendly") is the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such compounds are c ...
, but potency is nonetheless increased to some extent. While the acetate ester of Δ
9-THC is the best studied, the acetate esters of other isomers, especially
Δ8-THC but also
Δ10-THC are also known, as are other esters such as THC-O-propionate,
THC-O-phosphate,
THC hemisuccinate, THC hemiglutarate,
THC morpholinylbutyrate, THC piperidinylpropionate,
THC naphthoyl ester (THC-NE), and
THC-VHS, as well as the hydrogenated derivative
HHC-O-acetate and the ring-expanded
Abeo-HHC acetate, as well as related compounds such as
THC methylcarbonate.
Pharmacology
It is a metabolic
pro-drug, with its subjective effects being felt around 30 minutes after ingestion.
Psychedelic claims
In a 2023 study, anecdotal claims surrounding THC-O-acetate's supposed ability to initiate
psychedelic experience
A psychedelic experience (known colloquially as a trip) is a temporary altered state of consciousness induced by the consumption of a psychedelic substance (most commonly Lysergic acid diethylamide, LSD, mescaline, psilocybin mushrooms, or N,N- ...
s were shown to not be significant. Answers using the Mystical Experience Questionnaire (MEQ) were under the threshold of a true experience, and those who had used classical psychedelics such as
LSD
Lysergic acid diethylamide, commonly known as LSD (from German ; often referred to as acid or lucy), is a semisynthetic, hallucinogenic compound derived from ergot, known for its powerful psychological effects and serotonergic activity. I ...
or
psilocybin
Psilocybin, also known as 4-phosphoryloxy-''N'',''N''-dimethyltryptamine (4-PO-DMT), is a natural product, naturally occurring tryptamine alkaloid and Investigational New Drug, investigational drug found in more than List of psilocybin mushroom ...
consistently scored lower on the MEQ. When asked directly, 79% of the participants said it was either "not at all" or "a little" like a psychedelic experience.
History
THC acetate ester was investigated as a possible non-lethal incapacitating agent as part of the
Edgewood Arsenal experiments at some point between 1949 and 1975. It was noted to have about twice the capacity to produce
ataxia
Ataxia (from Greek α- negative prefix+ -τάξις rder= "lack of order") is a neurological sign consisting of lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes, and abnormalities in e ...
(lack of voluntary coordination of muscle movements) as did
THC when administered to
dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. ...
s.
[
]
Author D. Gold provided synthesis instructions for this compound (calling it "THC acetate") in his 1974 book ''Cannabis Alchemy: Art of Modern Hashmaking'', in which it is described as follows;
The U.S.
DEA first encountered THC-O-acetate as an apparent
controlled substance analogue of THC in 1978. It was made in an analogous manner to how aspirin (
acetylsalicylic acid
Aspirin () is the Generic trademark, genericized trademark for acetylsalicylic acid (ASA), a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and inflammation, and as an antithrombotic. Specific inflammatory conditions ...
) is made from willow bark (
salicylic acid
Salicylic acid is an organic compound with the formula HOC6H4COOH. A colorless (or white), bitter-tasting solid, it is a precursor to and a active metabolite, metabolite of acetylsalicylic acid (aspirin). It is a plant hormone, and has been lis ...
). The incident was described by Donald A. Cooper of the DEA thus:
A similar case reported in June 1995 in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
.The description of that case appears to indicate the convicted manufacturer was using D. Gold's book ''Cannabis Alchemy'' as a guide.
THC acetate was also reported to have been found by
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
police in 1995, again made by acetylation of purified cannabis extracts with acetic anhydride.
With passage of the
2018 United States farm bill (which eased legal restrictions on the cultivation of industrial
hemp
Hemp, or industrial hemp, is a plant in the botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial and consumable use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest ...
), ∆8-THC-O-acetate based
vaporizers and
edibles have become increasingly available in the United States and are now commonly sold at gas stations.
Toxicity
In 2022, researchers at Portland State University used an
e-nail to vaporize
CBD-acetate,
CBN
CBN, or cbn, may refer to:
Broadcasting organizations
* Radio stations in St. John's, Newfoundland:
** CBN (AM), CBC Radio One
** CBN-FM, CBC Music
* Chronicle Broadcasting Network, the predecessor of ABS-CBN
* CBN (Australian TV station), a TV ...
-acetate, and THC-O-acetate (referred to simply as "THC acetate") to screen for the presence of ketene formation when vaporizing. They reported that just like
Vitamin E acetate, all three of these cannabinoid acetates produced
ketene gas when heated. For this reason, the vaping of THC-O-acetate could be hazardous to health.
Legal status
United Kingdom
THC-O-acetate is a Class B drug in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
.
United States
The legal status of THC-O is in dispute within the United States. Since 2023, the
Drug Enforcement Administration
The Drug Enforcement Administration (DEA) is a Federal law enforcement in the United States, United States federal law enforcement agency under the U.S. Department of Justice tasked with combating illicit Illegal drug trade, drug trafficking a ...
has held the position that it is a controlled substance because "delta-9-THCO and delta-8-THCO do not occur naturally in the cannabis plant and can only be obtained synthetically". In September 2024, being the first court case specifically addressing this issue, the
United States Court of Appeals for the Fourth Circuit
The United States Court of Appeals for the Fourth Circuit (in case citations, 4th Cir.) is a United States federal court, federal court located in Richmond, Virginia, with appellate jurisdiction over the United States district court, district cou ...
rejected the foregoing DEA position and "set a legal hemp standard" by holding that THC-O is legal. The issue of THC-O legality has not been addressed by other circuits or by the Supreme Court and there remains a "hazy legal landscape" for hemp products.
Germany
On 27 June 2024, following the Ban of HHC, THC-O-Acetate was added to both the annex of
New Psychoactive Substances Act (NpSG) and the
Narcotic Drugs Act (BtMG) since it was not a naturally occurring cannabinoid.
Manufacture, sale and possession of the cannabinoid has since been fully outlawed.
See also
*
Acetylation
:
In chemistry, acetylation is an organic esterification reaction with acetic acid. It introduces an acetyl group into a chemical compound. Such compounds are termed ''acetate esters'' or simply ''acetates''. Deacetylation is the opposite react ...
*
Abeo-HHC acetate
*
Cannabidiol diacetate
*
Cod-THC
*
Nabitan
*
O-1057
*
O-2694
*
HHCP-O-acetate
*
THCP-O-acetate
References
{{DEFAULTSORT:Thc-O-Acetate
Cannabinoids
Acetate esters
Benzochromenes
Prodrugs
Heterocyclic compounds with 3 rings