<\/span><\/a><\/div>\n
\nHowever, means for selectively synthesizing natural type cis-whiskey lactone (A) having superior properties than those of trans-type isomer (D) as described above has not been known.<\/span><\/p>\n<\/div>\n<\/li>\n\n\u00a0<\/span><\/div>\nLiebigs Annalen der Chemie, No. 12, 1986, pages 2112 – 2122, disclose a method, how all four stereoisomers of 3-methyl-4-octanolide can be produced. It is taught to separate a racemic cis\/trans octanolide into the two cis- and the two trans-isomers chromatographically. Furthermore, it is disclosed how to hydrolyse a lactone ring with potassium hydroxide and to protect the carboxy group subsequently yielding the isopropyl carboxylic ester. Diastereomeric pairs of the acid-protected gamma-hydroxyacid are formed by reaction with an optically active carboxylic acid, and are separated from each other by liquid chromatography. It is disclosed how to perform the hydrolysis of the diastereomers and the relactonization to obain the four stereoisomers of whiskey-lactone. No reaction at the 4-hydroxy group is suggested to invert the configuration of the chiral centre<\/span><\/div>\n<\/li>\n\nSynthesis, No. 1, 1981, pages 1-28, discloses the use of diethyl azodicarboxylate and triphenylphosphine in synthesis and transformation of natural products. However, there is no indication for a combination of these documents. Furthermore, it is well-known that the Mitsunobu reaction proceeds according to Sn2 reaction mechanism. In the case of 3,4-trans compound (III) which is a substrate of the method of the present invention, the steric hindrance to the 4-methyl group is large because of the influence from the methyl group at a 3-position.<\/span><\/div>\n<\/li>\n<\/ul>\n\u00a0<\/span><\/p>\nPhysical data of the obtained cis-whiskey lactone are
\nBoiling Point : 124 – 126\u00b0C\/(17 mmHg) 2266 Pa
\n\u00b9H-NMR(CDCl\u2083) : \u03b4 0.92(3H, t, J = 7.0 Hz), 1.02(3H, d, J = 6.9 Hz), 1.20 – 1.75(6H, m), 2.20(1H, dd, J = 3.8 and 16.8 Hz), 2.51 – 2.64(1H, m), 2.70(1H, dd, J = 7.8 and 16.8 Hz), 4.40 – 4.48(1H, m) (ppm units)<\/p>\n
\u00a0<\/span><\/p>\n\u00a0<\/span><\/p>\n<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"excerpt":{"rendered":"Whisky Lactone Whisky lactone, also known as \u03b2-methyl-\u03b3-octalactone or\u00a0quercus lactone\u00a0(from the Latin for oak treeQuercus alba), is a flavouring found in American bourbon whiskies, and is also found in all types of oak. The flavour gets into the whisky when it’s matured in oak barrels. The pure molecule has a fierce, strong, and sweet smell… Continue reading Whisky lactone<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,4,1],"tags":[18,11,143,144,103,55,104],"_links":{"self":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/1177"}],"collection":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/comments?post=1177"}],"version-history":[{"count":6,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/1177\/revisions"}],"predecessor-version":[{"id":1199,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/posts\/1177\/revisions\/1199"}],"wp:attachment":[{"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/media?parent=1177"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/categories?post=1177"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/amcrasto.theeurekamoments.com\/wp-json\/wp\/v2\/tags?post=1177"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}