1,3,2-Dioxathiolane 2-oxides

Dioxathiolane oxides as epoxide equivalents and versatile synthons 98AHC(68)89. 

Similar elimination from 1,3,2-dioxathiolane -oxides (cyclic sulfites) has been studied and used along with an in situ trap (DBU/TMSC1) to obtain a tautomeric equivalent of a-oxocarboxylic acid ester (Scheme 14)... 

Trithioles and 1,3,2-dioxathiolanes. 1,2,3-Trithiolanes are prepared by reaction of alkenes with elemental sulfur . The synthesis of 1,3,2-dioxathiolane -oxides (cyclic sulfites) and 1,3,2-dioxathiolane S, -dioxides (cyclic sulfates) is discussed in comprehensive reviews <1997AHC(68)89, 2000T7051>. The most widely used method for the preparation of 1,3,2-dioxathiolane A-oxides 557 is the reaction of the corresponding 1,2-diols 556 with thionyl chloride in the presence of pyridine or triethylamine (Scheme 251). More reactive 1,3,2-dioxathiolane S,A-dioxides 558 are usually obtained by oxidation of sulfites 557 with sodium periodate, which is mediated by ruthenium tetroxide generated in situ from a catalytic amount of ruthenium trichloride <1997AHC89, 2000T7051, CHEC-III(6.05.10.3)183>. 

Lohray, B. B., Bhushan, V., 1,3,2-Dioxathiolane Oxides Epoxide Equivalents and Versatile Synthons,... 

Dioxathiolane Oxides Epoxide Equivalents and Versatile Synthons... 

The second chapter in this volume, 1,3,2-Dioxathiolane Oxides Epoxide Equivalents and Versatile Synthons, is authored by Dr. B. B. Lohray and Dr. V. Bhushan of the Reddy Research Foundation, Hyderabad, India. These compounds are cyclic sulfates and, over the past seven or eight years they have become important intermediates in organic synthesis. 

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