Thionocarbonic esters cyclic

During the time frame covered by this chapter, stannanes have been reported to have been involved in radical chemistry not involving the more traditional functionalities. For example, Marzi and coworkers reported that the reduction of cyclic thionocarbonates (e.g. 82) with Bu3SuH under standard radical conditions affords cyclic acetals that can then be further transformed into 1,2-diols (equation 57). This transformation represents a new approach to the protection of these diols. Zehl and Cech described the use of Bu3SnH in the reduction of azide (83) to the corresponding amine (equation 58) , while Hanessian and his associates reported the Ph3SnH-mediated free-radical reduction of the tertiary oxalate (84) (equation 59) . This transformation represents a departure from the more typical reduction of a pyridinethioneoxycarbonyl (PTOC) oxalate ester. ... 

Horton, D, Thomson, J K, Tindall, C G Jr., Unsaturated sugars via cycUc thionocarbonates, cyclic orthoformates, and disulfonic ester intermediates. Methods Carbohydr. Chem., 6, 297-301, 1972. 

Attempts to prepare compounds of this group by heating the derived 2, 3 -thionocarbonates with trimethyl phosphite have not met with the same success. From 5 -0-trityluridine, the 2,2 -anhydro-nucleoside was produced, instead of the cyclic ester, by treatment... 

Cyclic thionocarbonic acid esters from disulfurdicarbothionates by rearrangement fragmentation... 

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