ISSN:
0947-3440
Keywords:
Thioketones
;
Sulfurization
;
Sulfur ylides
;
Sulfur heterocycles
;
Conformational analysis
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
By treatment with elemental sulfur and a catalytic amount of sodium thiophenolate in acetone at room temp., the title compound 9 is converted to the bis-spiro derivatives of 1,2,4,5-tetrathiane, 13, and 1,2,3,5,6-pentathiepane, 14. The initial attack by the phenyl oligosulfide anion takes place at the C-atom of the thiocarbonyl group. There is 13C NMR evidence for the twist conformation 15 of the tetrathiane ring; dynamic 1H NMR led to ΔG≠ = 15.9 ± 1.0 kcal mol-1 for the enantiomerization. For the pentathiepane 14, twelve coalescence phenomena in the 1H and 13C NMR spectra point to ΔG≠ = 13.4 ± 0.2 kcal mol-1; the process is interpreted as a stereomutation on the pseudorotation circuit for twist-chair and chair. The MS of 13 reveals a diversity of fragmentation patterns with several “thiologous” sequences. By prolonged treatment with the thiophenolate catalyst, 13 and 14 are converted to a γ-butyrodithiolactone 36 in a Baeyer-Villiger type reaction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.199719970730
