tert-Butanol

tert-Butanol

Names
IUPAC name 2-Methylpropan-2-ol
Other names 2-Methyl-2-propanol tert-Butyl alcohol t-BuOH Trimethyl carbinol TBA
Identifiers
Jmol-3D images	Image
SMILES CC(C)(C)O
Properties
Chemical formula	(CH3)3COH C4H10O
Molar mass	74.12 g/mol
Appearance	Colorless solid (<25 °C) or liquid (>25 °C)
Odor	Camphor-like
Density	0.7886 g/cm3 (at 20 °C)
Melting point	25.81 °C (78.46 °F; 298.96 K)
Boiling point	82.3 °C (180.1 °F; 355.4 K)
Solubility in water	Miscible
Solubility	Miscible with diethyl ether, ethanol, isopropanol Soluble in chloroform
Vapor pressure	4.1 kPa (at 20 °C)
Acidity (pKa)	16.54
Thermochemistry
Std molar entropy (So298)	189.5 J·K−1·mol−1
Std enthalpy of formation (ΔfHo298)	−360.04–−358.36 kJ·mol−1
Hazards
Safety data sheet	ScienceLab
Flash point	11 °C
Lethal dose or concentration (LD, LC):
LD50 (Median dose)	3,559 mg/kg (rabbit, oral) 3,500 mg/kg (rat, oral)
Related compounds
Related compounds	Butanol sec-Butanol Isobutanol tert-Amyl alcohol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

tert-Butanol or tert-Butyl alcohol (TBA), also known as 2-methylpropan-2-ol (2M2P), is the simplest tertiary alcohol, with a formula of (CH₃)₃COH (sometimes shortened to t-BuOH). One of the most interesting characteristics of t-BuOH is that it can be a clear liquid or a colorless solid depending on the ambient temperature and season, with a melting point around 25 °C.

Properties

Chemical

Being a tertiary alcohol, tert-butanol cannot be oxidized to an aldehyde or ketone, like primary or secondary alcohols can.

Physical

tert-Butanol is a colorless solid at standard conditions, but has a very high melting point for a simple alcohol, of only 25.8 °C. It's boiling point is 82.3 °C. t-BuOH is miscible with water and has a camphor-like smell.

Availability

t-BuOH is sold by various chemical suppliers.

It can also be found as fuel additive, though the percentage is small.

Minute amounts are sometimes added in rubbing alcohol as a denaturing agent, though you will need a very large amount of rubbing alcohol to extract any useful amounts of t-BuOH. Most types have around 0.5 g/L of rubbing alcohol.

Preparation

tert-Butanol can be made via acid catalyzed hydrolysis of methyl tert-butyl ether, though if a hydrohalic acid is used, the corresponding alkyl halide is formed.

It can also be produced by reacting very dry acetone with methylmagnesium halide (a Grignard reagent) or methyllithium (an organolithium reagent).

Projects

• Make methyl tert-butyl ether
• Make potassium tert-butoxide

Handling

Safety

tert-Butanol poses low toxicity, though it can be irritant. It is also flammable. Tert-butanol is poorly absorbed through skin, but rapidly absorbed in the organism if inhaled or ingested. Toxicity of single doses is usually low but high doses will produce a sedative or anesthetic effect.

Storage

tert-Butanol should be stored in closed bottles, preferably glass. If the temperature inside the storage area drops below 25 °C, such as during cold seasons, rain or night, t-BuOH will freeze. This is not usually a problem, as it does not expand upon freezing and is also less volatile when solid, but getting it out of the bottle may become frustrating.

Disposal

tert-Butanol can be safely burned, either pure or dissolved in a more flammable solvent. It can also be destroyed with Fenton's reagent, though this is not always necessary.

References

Relevant Sciencemadness threads

• OTC tert-Butanol
• tert-Butyl Alcohol
• Making t-butanol