Tetralin (1,2,3,4-tetrahydronaphthalene) is a

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...

having the

chemical formula A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...

C₁₀H₁₂. It is a partially

hydrogenated Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organi ...

derivative of

naphthalene Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white Crystal, crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 Parts-per notation ...

. It is a colorless liquid that is used as a

hydrogen-donor solvent A hydrogen-donor solvent is hydrocarbon that transfers hydrogen to hydrogen-poor substrates, such as coal. The hydrogen-poor substrates could be a solute or suspension. The classic hydrogen-donor solvent (or just donor solvent) is tetrahydronapht ...

Production

Tetralin is produced by the catalytic hydrogenation of naphthalene. Tetralin synthesis 01

Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene ( decalin). Rarely encountered is dihydronaphthalene ( dialin).

Laboratory methods

In a classic

named reaction A name reaction (or named reaction) is a chemical reaction named after its discoverer(s) or developer(s). Among the tens of thousands of organic reactions that are known, hundreds of such reactions are typically identified by the eponym. Well-known ...

called the Darzens tetralin synthesis, named for

Auguste Georges Darzens Auguste Georges Darzens (12 July 1867 in Moscow, Russia – 10 September 1954) was a Russia, Russian-born French people, French organic chemist. Biography From 1886 he studied at the École Polytechnique in Paris under Édouard Grimaux, Louis ...

(1926),

derivative In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is t ...

s can be prepared by intramolecular

electrophilic aromatic substitution Electrophilic aromatic substitution (SEAr) is an organic reaction in which an atom that is attached to an aromatic ring, aromatic system (usually hydrogen) is replaced by an electrophile. Some of the most important electrophilic aromatic substitut ...

reaction of a 1-aryl-pent-4-ene using concentrated

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

Uses

Tetralin is used as a

, for example in coal liquifaction. It functions as a source of H₂, which is transferred to the coal. The partially hydrogenated coal is more soluble. It has been used in

sodium-cooled fast reactor A sodium-cooled fast reactor is a fast neutron reactor cooled by liquid sodium. The initials SFR in particular refer to two Generation IV reactor proposals, one based on existing liquid metal cooled reactor (LMFR) technology using mixed oxide fue ...

s as a secondary coolant to keep sodium seals around pump impellers solidified; however its use has been superseded by NaK.US Atomic Energy Commission (1961) SRE Core Recovery
Remediation method after a failure in the moderator cans due to a crack in the secondary coolant tubes in the SRE, Spring 1959. This caused a leak of Tetralin into the reactor. It is also used for the laboratory synthesis of

hydrogen bromide Hydrogen bromide is the inorganic compound with the formula . It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temper ...

: :C₁₀H₁₂ + 4 Br₂ → C₁₀H₈Br₄ + 4 HBr The facility of this reaction is in part a consequence of the moderated strength of the

benzyl In organic chemistry, benzyl is the substituent or molecular fragment possessing the structure . Benzyl features a benzene ring () attached to a methylene group (). Nomenclature In IUPAC nomenclature, the prefix benzyl refers to a substituent ...

ic C-H bonds.

Safety

(rats, oral) is 2.68 g/kg. Tetralin induces

methemoglobinemia Methemoglobinemia, or methaemoglobinaemia, is a condition of elevated methemoglobin in the blood. Symptoms may include headache, dizziness, shortness of breath, nausea, poor muscle coordination, and blue-colored skin (cyanosis). Complications ma ...

References

{{Authority control Aromatic solvents Aromatic hydrocarbons