trans-3-Methyl-4-octanolide

trans-3-Methyl-4-octanolide, also called trans-β-methyl-γ-octalactone is a chemical compound of the lactone family with formula C
9
H
16
O
2
. It exists in two stereoisomers: (3R,4S) and (3S,4R).

trans-3-Methyl-4-octanolide
Names
IUPAC name
(4R,5S)-5-butyl-4-methyldihydrofuran-2(3H)-one
Identifiers
3D model (JSmol)
ChemSpider
UNII
  • InChI=1S/C9H16O2/c1-3-4-5-8-7(2)6-9(10)11-8/h7-8H,3-6H2,1-2H3/t7-,8+/m1/s1 checkY
  • (4R,5S): InChI=1S/C9H16O2/c1-3-4-5-8-7(2)6-9(10)11-8/h7-8H,3-6H2,1-2H3/t7-,8+/m0/s1
  • (4R,5S): O=C1O[C@@H](CCCC)[C@@H](C1)C
  • (4S,5R): CCCC[C@H]1OC(=O)C[C@@H]1C
Properties
C9H16O2
Molar mass 156.222
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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The (3S,4R) form is found in whiskey and other alcoholic beverages that have been aged in oak barrels, together with the more important cis isomer.[1][2] It has a coconut, celery or fresh wood aroma, that can be detected by humans at the concentration of 20 μg/L in air.[3] A mixture of the cis and trans isomers is repellent for mosquitos and flies.[4]

The (3S,4R) isomer is extracted by the alcoholic beverage from some precursor substances in the oak wood.[5] It can be synthesized in various ways.[3][6][7]

See also

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3-Methyl-4-octanolide, cis and trans isomers.

References

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  1. ^ "Aromas and Flavours". Wine-Pages.com. Archived from the original on 2007-10-18. Retrieved 2007-12-18.
  2. ^ Hans-Dieter Belitz, Peter Schieberle, and Werner Grosch (2004) Food Chemistry, page 383. Springer, ISBN 3-540-40818-5
  3. ^ a b Eric Masson, Raymond Baumes, Christine Le Guernevé, and Jean-Louis Puech (2000) Identification of a Precursor of β-Methyl-γ-octalactone in the Wood of Sessile Oak (Quercus petraea (Matt.) Liebl.). J. Agric. Food Chem. volume 48, pages 4306-4309
  4. ^ Yukio Suzuki, Wakako Mori, Hiroyuki Ishizone, Koichi Naito, and Toshio Honda (1992) Concise Enantiospecific Syntheses of (+)-Eldanolide and (−)-cis-Whisky Lactone. Tetrahedron letters, volume 33, pages 4931-4932 doi:10.1016/S0040-4039(00)61237-6
  5. ^ Masuda and Nishimura (1971), Branched nonalactones from some Quercus species. Phytochemistry, volume 10, pages 1401-1402.
  6. ^ Hisashi Nishikori, Katsuji Ito, and Tsutomu Katsuki (1998) A short-step synthesis of trans-whisky lactone by an asymmetric Michael reaction. Tetrahedron: Asymmetry, volume 9, pages 1165–1170.
  7. ^ Katsuji Ito, Miwa Yoshitake and Tsutomu Katsuki (1995), Enantioselective Synthesis of trans-Whisky Lactone by Using Newly Developed Asymmetric Ring Expansion Reaction of Oxetane as a Key Step. Chemistry Letters, volume 24, issue 11, page 1027 doi:10.1246/cl.1995.1027