10.1016/S0040-4039(00)96614-0
The research focuses on the synthesis of chiral oxetanes from sugar lactones, with the aim of creating derivatives of 3,5-anhydro-1,2-O-isopropylidene-α-D-glucuronic acid and 3,5-anhydro-1,2-O-isopropylidene-S-L-iduronic acid. The purpose of this study was to explore the ring contraction reactions of triflates of α-hydroxy-T-lactones, which provide an approach to synthesizing chiral polyfunctionalized oxetanes from sugars. The researchers used various chemicals in their process, including 1,2-O-isopropylidene-5-O-trifluoromethanesulphonyl-α-D-glucuronolactone (1), benzylamine, potassium carbonate, triflic anhydride, sodium azide, and lithium aluminum hydride. The conclusions drawn from the research indicate that the oxetane system is chemically and configurationally stable under the reaction conditions used, with no epimerization observed. The study suggests that the ring contraction of the glucuronolactone triflate (1) to the oxetanes (9) and (10) involves epimerization prior to the formation of the oxetane ring. The findings also indicate that this procedure may offer a flexible approach to the synthesis of highly substituted and functionalized chiral oxetanes, which could be relevant for the synthesis of oxetanocin and C-nucleoside analogues.