2,5-Undecanedione

2,5-Undecanedione 2,5-Undecanedione.svg Structural formula of 2,5-Undecanedione Undecane-2,5-dione 7018-92-0 correct CAS 230-297-4 81489 Q83097698 F8UB9Q3X7Y 73524 1S/C11H20O2/c1-3-4-5-6-7-11(13)9-8-10(2)12/h3-9H2,1-2H3 ZHMCDZHVHDFSHO-UHFFFAOYSA-N CCCCCCC(=O)CCC(=O)C 11 20 2 2,5-Undecanedione is a γ-diketone in which the two carbonyl groups are separated by two methylene groups. Synthesis Heinz Hunsdiecker described the synthesis of 2,5-undecanedione from 5-methylfurfural in 1942. 5-Methylfurfural 1 is first reacted with methyl propyl ketone 2 in an aldol condensation reaction to form an α,β-unsaturated carbonyl compound 3. The double bond of the side chain condensation product is reduced with sodium amalgam. The intermediate 4 is then converted to 2-methyl-5-hexylfuran 5 in a Wolff-Kishner reduction using hydrazine. An acid-catalyzed reaction at 120 C F cleaves the furan ring, producing 2,5-undecanedione 6.Heinz Hunsdiecker 1942-05-06 10.1002/cber.19420750502 5 447–454 Berichte der Deutschen Chemischen Gesellschaft Über das Verhalten der γ-Diketone, I. Mitteilung 75 500px|Synthesis of 2,5-undecanedione from 5-methylfurfural An alternative route of synthesis starts with heptanal 1. First, the carbonyl group is protected with 1,3-propanedithiol 2, producing a dithiane 3. The dithiane is deprotonated using n-Butyllithium in tetrahydrofuran, and alkylated using 1,3-dichloro-2-butene 4 to give the intermediate 5. Hydrolysis of the dithioacetal protecting group with concentrated sulfuric acid yields 2,5-undecanedione 6, which can be worked up and purified using Girard's reagent TPubChem Girard's reagent T https://pubchem.ncbi.nlm.nih.gov/compound/67156 2024-11-05 pubchem.ncbi.nlm.nih.gov en in methanol.Ho Tse-Lok Ho Honor C. Wong C. M. 1973-01-15 A Synthetic Route to Dihydrojasmone; Sulfuric Acid as Dethioacetalization Agent http://www.nrcresearchpress.com/doi/10.1139/v73-023 Canadian Journal of Chemistry en 51 2 153–155 10.1139/v73-023 0008-4042 subscription 600px|Synthesis of 2,5-undecanedione from heptanal Uses 2,5-Undecanedione is used in the Hunsdiecker condensation de Hunsdiecker-Kondensation, a reaction developed by Heinz Hunsdiecker in 1942 to produce cyclopentenones from γ-ketones, in sodium hydroxide solution to produce the fragrance dihydrojasmone: 200px|Synthesis of dihydrojasmone from 2,5-undecanedione References Category:Diketones