Tetralin
Tetralin is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent.
Production
Tetralin is produced by the catalytic hydrogenation of naphthalene.Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene. Rarely encountered is dihydronaphthalene.
Laboratory methods
In a classic named reaction called the Darzens tetralin synthesis, named for Auguste Georges Darzens, derivatives can be prepared by intramolecular electrophilic aromatic substitution reaction of a 1-aryl-pent-4-ene using concentrated sulfuric acid,Image:Darzens Synthesis of Tetralin Derivatives.svg|thumb|center|400px|Darzens synthesis of tetralin derivatives
Uses
Tetralin is used as a hydrogen-donor solvent, 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fast reactors as a secondary coolant to keep sodium seals around pump impellers solidified; however its use has been superseded by NaK.
It is also used for the laboratory synthesis of hydrogen bromide:
The facility of this reaction is in part a consequence of the moderated strength of the benzylic C-H bonds.