Syntheses of Both Enantiomers of 1,7-Dioxaspiro[5.5]undecane: Pheromone Components of the Olive Fruit-Fly Dacus oleae from a New Chiral Intermediate, the (SS)-2-(p-Tolylsulfinyl)prop-2-en-1-ol

Abstract

Both enantiomers of 1,7-dioxaspiro[5.5]undecane, the pheromone components of the olive fruit-fly Dacus oleae have been synthesized from a new chiral sulfoxide, (Ss)-2-(p-tolylsulfinyl)prop-2-en-1-ol via hetero Diels-Alder reaction, chromatographic separation of the diastereomers on a silica gel column and desulfurization over Raney nickel as key steps.

The hetero-Diels–Alder approach to spiroketals

“…24 Reactive heterodienes containing a C3 chiral sulfinyl group have been successfully employed by Maignan and Hayes (Scheme 14). 25 Cycloaddition between methylene furan 50 and the chiral sulfoxide heterodiene 49 gave the diastereoisomers 51a and 51b which were easily separated by chromatography. Hence, starting from enantiopure sulfinyl heterodiene 49 enantiopure spiroketals could be obtained after sulfinyl cleavage.…”

Recent developments in chiral non-racemic sulfinyl group chemistry in asymmetric synthesis

“…112 The previously described 2-(p-tolylsulfinyl)acrolein 141 underwent a cycloaddition reaction with 2-methylenetetrahydropyran to afford a 1:1 mixture of diastereoisomers in 60% total yield. These could be separated and converted, by hydrogenolytic sulfinyl-group cleavage followed by double bond hydrogenation, to the two enantiomers of the spiroketal.…”

Synthesis of spiroacetals using functionalised titanium carbenoids

“…Exocyclic enol ethers have been used to prepare spiroacetals by cycloadditions, [3][4][5][6][7][8] or through acid-induced cyclisation of alcohols. [9][10][11][12][13] Such enol ethers have been metathesis, 22 Baeyer-Villiger oxidation of cyclic ketones 23 and by oxidation of sugars, 24 as well as by methods which would be appropriate for preparation of acyclic esters.…”