Thiolane oxides synthesis

A method for the stereospecific synthesis of thiolane oxides involves the pyrolysis of derivatives of 5-t-butylsulfinylpentene (310), and is based on the thermal decomposition of dialkyl sulfoxides to alkenes and alkanesulfenic acids299 (equation 113). This reversible reaction proceeds by a concerted syn-intramolecular mechanism246,300 and thus facilitates the desired stereospecific synthesis301. The stereoelectronic requirements preclude the formation of the other possible isomer or the six-membered ring thiane oxide (equation 114). Bicyclic thiolane oxides can be prepared similarly from a cyclic alkene301. 

Thio-Claisen rearrangement 746-748 Thioketene 5-oxides photolysis of 878 reactions of 277 Thiolane dioxides formula of 382 NMR spectra of 460 reactions of 604 synthesis of 461 Thiolane oxides 747 formula of 382 IR spectra of 461 synthesis of 461, 462, 752 Thiolanes, photolysis of 881 Thiolene dioxides formula of 382 NMR spectra of 460 reactions of 464, 465 synthesis of 461 Thiolene oxides formula of 382 synthesis of 461, 746 Thiols... 

Jones and Lewton250 have also demonstrated the utility of the intramolecular addition of sulfenic acids to olefins as a stereospecific method for the synthesis of thiolan 1-oxides. 

Oxathiane 2-oxides aie fonned by the oxidative ring expansion of 2-alkylthio-2-benzylthiolane 1-oxides brought about by [bis(trifluoroacetoxy)iodo]benzene. That the reaction is only successful with the (lR )-diastereoisomeis is attributed to chelation between the nucleophilic S and O atoms and the hypervalent iodine <99EJ0943>. A diazo-mediated thiolane ring expansion is the key step in a synthesis of the acenaphtho-[U-b][l,4]oxathiine system <99JCS(P2)755>. 

A new one-pot Pummerer phosphorylation reaction allowed an efficient synthesis of 2-phosphonathiolanes (173) starting from thiolane S-oxide (174) and trialkyl phosphites. The S-oxidation of the cyclic compounds (173) occurred with a total trans-stereoselectively (Scheme 44). ... 

Lohray BB, Bhushan V (1995) Enantioselective Synthesis of Taxol Side Chain via Regio- and Stereoselective Reaction of 4(R)-carbethoxy-5(S)-phenyl-l,3,2-dioxa-thiolane-2-oxide. Indian J Chem Sect B Org Chem Incl Med Chem 34B 471... 

Full details have appeared on the synthesis of racemic 4-thiotetrose derivatives by Pummerer rearrangement of esters of thiolan-3,4-diol 1-oxides (i.e. 

Thiolans, Thians, Thiepans, Thiocans, and their Oxides and Dioxides Synthesis.—The intramolecular trapping of a sulphenic acid by a carbon-carbon double bond constitutes a new stereospecific route to cw-2-substituted thiolans and thian 1-oxides. Thus 5-t-butylsulphinylpent-l-ene (1), when heated at... 

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... 

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