Tertiary amyl alcohol

tert-Amyl alcohol (TAA), systematic name 2-methylbutan-2-ol (2M2B), is a branched pentanol. tert-Amyl alcohol (TAA), systematic name 2-methylbutan-2-ol (2M2B), is a branched pentanol. Historically TAA has been used an anesthetic and more recently it has also been used as a recreational drug similar to ethanol because TAA is mostly a positive allosteric modulator for GABAA receptors in the same way as ethanol. This means that TAA causes calming effects within the central nervous system by interacting indirectly (allosterically) with GABAA receptors and enhances (positive effect) their activity. TAA is a colorless liquid with a burning flavor and a very unpleasant odor which has been described as being similar to paraldehyde with a hint of camphor. TAA can be produced via fermentation, but it is primarily produced through other means. TAA remains liquid at room temperature making it a useful alternative solvent to tert-butyl alcohol. TAA is primarily produced by the hydration of 2-methyl-2-butene in the presence of an acidic catalyst. Fusel alcohols including TAA are grain fermentation byproducts and therefore trace amounts of TAA are present in many alcoholic beverages. Trace levels of TAA have also been detected in various foods, including fried bacon, cassava, rooibos tea. Between about 1880 and 1950 TAA was used as an anesthetic with the contemporary name of amylene hydrate. In 1930's TAA was mainly used as a solvent for tribromoethanol (TBE), forming Avertin at a 0.5:1 volume ratio of TAA to TBE. TAA was rarely used as a sole hypnotic because of the existence of more efficient drugs. Avertin is a brand-name for now discontinued TAA and TBE solution made by Winthrop Laboratories. Tertiary alcohols like TAA generally can not be oxidised to aldehyde or carboxylic acid metabolites which are often toxic (e.g. acetaldehyde and formic acid from ethanol and methanol). However, like other tertiary alcohol based anesthetics (e.g. methylpentynol, ethchlorvynol) TAA was eventually superseded by safer and more effective agents. The use of TBE and TAA solution was also discontinued in humans in the late 1940s, as back then TBE was noted to be harmful for the liver just like chloroform, which was also used as an anesthetic at the time. TBE and TAA solution is still used as a short-acting anesthetic for laboratory mice and rats. Nowadays TAA has found use as a recreational drug.