4- Hydroxy-l,2-dithiolane

An empirical formula C3H6O2S2 has been deduced for both compounds from elemental analysis and judging from the results of the UV, IR, NMR and MS spectra analyse, both compounds were apparently either of the cis- and trans-isomers of 4-hydroxy-l,2-dithiolane-1-oxide. 

BRUGIEROL, TRANS- AND CIS-4-HYDROXY-l,2-DITHIOLANE-l-OXIDE, Tetrahedron Lettersy 29 2959 972). 

Cyclic Disulphides.— Most of the syntheses of these types of compounds involved oxidation of the open-chain dithiols. Asparagusic acid, or 1,2-di-thiolan-4-carboxylic acid, a new plant-growth inhibitor, has been isolated from extracts of etiolated asparagus and its structure confirmed by synthesis. Brugeriol and isobrugeriol, trans- and cis-4-hydroxy-l,2-dithiolan... 

I46a The condensation of the dithioacids with a-halogen ketones does not always produce j3-keto dithioesters (223). Somewhat surprisingly in several instances the reaction under mild alkaline conditions resulted in spontaneous ring closure to form the 4-hydroxy-l,3-dithiolan-2-ylidene derivatives, which in general under acidic treatment yield l,3-dithioI-2-ylidene derivatives (Section III, A, 2,c).l46b... 

Literature on the stability of individual cydk disulfides covers (i) compounds that polymerize on standing like 3,3-dimethyl-1 -dithiolaiK [124,12, 3-hydroxy-l,2-dithiolane [126] and iV-phenyl-4-oxo-5-aza-l,2-dithia-cyclohexane [127,128] ii) compoimds which polymerizes on heating such as dibenzo-lA5,6-tetrathiocin [129] and iii) compounds that polymeixK in neat form when a catalyst is added, such as cis-l,2-dithiacyclohex-4-aie [130] and l-oxa-4,5-dithiacycloheptane [13, 119, 130]. Detailed study of the stability of cyclic disulfides towards polymerization revealed that 1,2-dithiai are the only class of simple cyclic disulfides that is thermodynamically staUe with respect to its polymerization in the melt or as concentrated solutions [131]. 

Im Gegensatz dazu fiihrt die Reduktion von 4-Hydroxymethyl-2-phenyl-l,3-dithiolan mit Natrium/fl. Ammoniak und Athanol zu 1 -Hydroxy-propandithiol-(2,3)A ... 

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