Structure-Odour Correlation, Part XXIII.2-Alkyl-3a-methyltetrahydro-4-oxa-l,3-dithia- and −3,4-dioxa-1-thia-pentalenes
✍ Scribed by Peter Weyerstahl; Rainer Hauck
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 474 KB
- Volume
- 11
- Category
- Article
- ISSN
- 0882-5734
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✦ Synopsis
The 2-alkyl-3a-methyl-tetrahydro-4-oxa-1,3-dithiapentalenes la-f were prepared from the chloropentanone 4, the a-bromo thioacetates 9a-f and H2S/NEt3 via the labile intermediates 6a-f. Likewise, the 3,4-dioxa-l-thia analogues 2a-f were obtained from 4 and the a-bromoacetates 10a-f via lla-f. The stereochemistry of the ring fusion and the syn-or anti-position of the 2-alkyl group were assigned by NOED spectra. Flavour evaluation showed that l b and c possess similar onion-like, meaty, metallic and sulphury notes as described for the parent compound la. The taste of 2a-f in general exhibits meaty, sulphury, thiamine-like and fatty tonalities. KEYWORDS structuredour correlation; tetrahydro-4-oxa-1,3-dithiapentalene; tetrahydro-3,4-dioxa-l-thiapentaiene; thiamine odour compound (TOC); 'H-NMR; I3C-NMR 'H-NMR: Bruker AM 400. I3C-NMR Bruker AH 270 with DEPT program; NMR assignments were clarified by 'H, 'H and 'H, 13C COSY and NOED spectra. IR: CCL, Perkin-Elmer 881. MS: MAT 711, direct inlet (70 eV). GC-MS: Varian 3700 with 25 m CP Sil5 CB column, i.d. 0.25 mm, combined with Varian MAT 44 S, carrier gas. He. GC: Packard 437A with a 30 m CP Sil5 CB column, i.d. 0.25 mm, carrier gas N2. Flash CCC 0882-57341%/0402038 0 1996 by John Wiley & Sons, Ltd.