Tetrahydropyran 3342424 216108429 2008-05-31T02:56:20Z Cacycle 83784 + [[Category:Ethers]] {{Chembox new | Name = Tetrahydropyran | ImageFileL1 = Tetrahydropyran.png | ImageSizeL1 = 80px | ImageNameL1 = Tetrahydropyran | ImageFileR1 = Oxane-3D-vdW.png | ImageSizeR1 = 100px | ImageNameR1 = THP | IUPACName = Tetrahydropyran | Section1 = {{Chembox Identifiers | CASNo = 142-68-7 | SMILES = C1CCCCO1 }} | Section2 = {{Chembox Properties | Formula = C<sub>5</sub>H<sub>10</sub>O | MolarMass = 86.13 g/mol | Density = 0.880 g/cm<sup>3</sup> | MeltingPtC = -45 | BoilingPtC = 88 }} }} '''Tetrahydropyran''', or '''oxane''', is the [[organic compound]] consisting of a saturated six-membered ring containing five carbon atoms and one oxygen atom. The tetrahydropyran ring system is the core of [[pyranose]] sugars. In [[organic synthesis]], the 2-tetrahydropyranyl group is used as a [[protecting group]] for [[alcohol]]s.<ref>{{OrgSynth | title = Methyl 4-Hydroxy-2-butynoate | author = R. A. Earl L. B. Townsend | collvol = 7 | collvolpages = 334 | year = 1990 | prep = cv7p0334}}</ref><ref>{{OrgSynth | title =<nowiki>Diethyl [(2-Tetrahydropyranyloxy)methyl]phosphonate</nowiki> | author = Arthur F. Kluge | collvol = 7 | collvolpages = 160 | year = 1990 | prep = cv7p0160}}</ref> Reaction of the alcohol with [[dihydropyran]] forms a tetrahydropyranyl ether, protecting the alcohol from a variety of reactions. The alcohol can later be restored readily by acidic [[hydrolysis]] with formation of 5-hydroxypentanal. :[[Image:THP ether.png|500px|THP protective groups]] One classic procedure for the [[organic synthesis]] of tetrahydropyran is by [[hydrogenation]] with [[Raney nickel]] of dihydropyran.<ref>{{OrgSynth | title = Tetrahydropyran | author = D. W. Andrus; John R. Johnson | collvol = 3 | collvolpages = 794 | year = 1955 | cv3p0794}}</ref> ==See also== * [[Tetrahydrofuran]] (THF) * [[Pyran]] ==References== <references/> [[Category:Ethers]] [[Category:Oxygen heterocycles]] [[Category:Protecting groups]] [[Category:Ether solvents]] [[de:Tetrahydropyran]] [[nl:Tetrahydropyraan]] [[ja:テトラヒドロピラン]]