90180-88-4Relevant articles and documents
Elucidation of the 1,3-sulfanylalcohol oxidation mechanism: An unusual identification of the disulfide of 3-sulfanylhexanol in sauternes botrytized wines
Sarrazin, Elise,Shinkaruk, Svitlana,Pons, Monique,Thibon, Cecile,Bennetau, Bernard,Darriet, Philippe
body text, p. 10606 - 10613 (2011/05/11)
A four-step purification method was developed to isolate a citrus odorant detected by gas chromatography-olfactometry (GC-O), which was apparently specific to Sauternes botrytized wines. A fragmentation pattern of the odorant was obtained by multidimensional gas chromatography- mass spectrometry- olfactometry (MDGC-MS-O). The exact mass measurement was used to determine its elemental formula as C6H12OS. On the basis of these data, the unusual structure of 3-propyl-1,2-oxathiolane was synthesized and characterized for the first time. This confirmed its identification. Its occurrence in Sauternes wine extracts was demonstrated to result from the thermal oxidative degradation of 3-sulfanylhexanol disulfide (3,3'-disulfanediyldihexan-1-ol) in the GC injector. This disulfide was synthesized and then firmly identified for the first time in Sauternes wine. Although the presence of 3-sulfanylhexanol oxidation products had previously been reported in natural extracts (but not wine), the full oxidation pathway from 3-sulfanylhexanol to 3-propyl-γ-sultine via 3,3'- disulfanediyldihexan-1-ol was clearly established for the first time. Because the disulfide has mainly been detected in Sauternes botrytized wines, this finding suggested a singular reactivity of 3-sulfanylhexanol in botrytized wines, thus opening up a wide range of new opportunities in wine chemistry.
Intramolecular sulfur transfer in N-enoyl oxazolidine-2-thiones promoted by Bronsted acids. Practical asymmetric synthesis of β-mercapto carboxylic acids and mechanistic insights
Palomo, Claudio,Oiarbide, Mikel,Lopez, Rosa,Gonzalez, Pedro B.,Gomez-Bengoa, Enrique,Saa, Jose M.,Linden, Anthony
, p. 15236 - 15247 (2007/10/03)
The ability of Bronsted acids alone to efficiently promote the sulfur transfer process in N-enoyl oxazolidine-2-thiones to give β-mercapto carbonyl derivatives is demonstrated. The reactions proceed with essentially perfect diastereocontrol for a range of alkyl-substituted N-enoyl oxazolidine-2-thiones (d.r. regularly above 98:2) and high selectivity for most aryl-substituted counterparts (d.r. typically above 92:8). Importantly, the reaction works remarkably well in β,β-disubstituted N-enoyl oxazolidine-2-thiones as well, giving rise to quaternary C-S stereocenters in selectivities usually above 95:5. The relative efficiency of a range of acids (trifluoroacetic, difluoroacetic, acetic, triflic) is assessed showing TFA and TfOH as the most efficient and acetic acid as a totally inefficient reaction promoter. The new procedure complements the Lewis acid promoted reaction previously described by our group in two aspects: First, stereodivergent results are obtained for the Lewis acid or Bronsted acid promoted reactions of β,β-disubstituted enoyl compounds. Second, while the Bronsted acid promoted reactions are stereospecific, providing a good correlation between the substrate E/Z configuration and products stereochemistry, the reactions mediated by Lewis acids (BF3/OEt2) provide invariant d.r. values regardless of the E/Z composition of the starting olefin. The synthetic value of the method is illustrated by (a) removal of the oxazolidinone moiety from the rearranged products under reducing conditions (NaBH4, H 2O-THF) which yields β-mercapto alcohols and (b) treatment with Sm(OTf)3 in MeOH which affords the corresponding β-mercapto carboxylic esters, both categories of compounds being isolated in up to 97% ee. Remarkably, the method constitutes the first general approach to highly enantioenriched building blocks bearing a quaternary C-S stereocenter. On the other hand, spectroscopic and inhibition experiments are carried out that demonstrate the participation of protons also in the Lewis acid promoted reactions. Finally, the computational studies carried out at the B3LYP/6-31G* level give support for an activation of the substrate enoyl by complexation with two molecules of either the Bronsted or Lewis acid and serve to explain the stereochemical outcome of the reactions.
Fragrance precursors
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, (2008/06/13)
The invention relates to fragrance precursors, In particular, the invention relates to the use of several classes of compounds which may act as fragrance precursors, e,g., in cosmetic products such as deodorants and antiperspirants and in laundry products such as detergents and fabric softners. These compounds are odorless, but upon contacting the skin as example, in skin care compositions or in personal care compositions, produce fragrances. The compounds also produce fragrances when used in the presence of lipases, e.g. as used in (laundry) detergents, thus providing a prolongation of the fabric scenting effect. The compounds under consideration are compounds of the formula I: The substituents are defined in the specification.
