Although phenylmethylene-protected vinyl sulfone-modified carbohydrate 2alpha reacts with both primary and secondary amines in Michael fashion to afford aminated products, only primary amines react with the dibenzyl-protected 3alpha, 6-O-trityl-protected 4alpha, and unprotected 5alpha, highlighting for the first time the remarkable influence of protecting groups on the reaction patterns of vinyl sulfone-modified carbohydrates. The quantum chemical calculations suggest that the Michael addition of amines and proton transfer to vinyl sulfone-modified carbohydrates 2alpha and 5alpha are possible via relay process in a concerted mechanism. These calculations reveal that the addition of primary amines to vinyl sulfone-modified carbohydrate is preferential due to the low activation energy barriers, whereas the addition of secondary amines has relatively higher activation energy barriers. The theoretical conclusions are in line with the experimental observations.

A single sugar molecule containing three functional groups, namely a masked aldehyde, a Michael acceptor and a leaving group, reacts with a series of β‐dicarbonyl compounds and related reagents to form up to three new bonds and up to three new stereocenters. The configuration of the sugar derivative controls the diastereoselectivity in the formation of all the new bonds without a requirement for any external reagent for asymmetric induction. This “Chiral pool” based diversity‐oriented synthetic strategy has led to the formation of a series of furofurans based on different scaffolds and with appendage variations, and also to a hitherto unknown family of bicyclic 3,8‐dioxabicyclo[4.2.1]nonanes.

A vinyl sulfone modified bicyclic sugar molecule undergoes efficient Michael addition of hetero‐ and carbon nucleophiles to afford single diastereomers. The same molecule consisting of two other masked functional groups, namely an aldehyde and an oxocarbonium ion, turned out to be a unique synthetic intermediate. The adducts generated from this Michael acceptor and a series of β‐dicarbonyl compounds and related reagents after acid treatment afforded a new class of furo[2,3‐c]pyrans, forming up to three new bonds and three stereocenters. In‐built chirality centers of the sugar derivative controlled the diastereoselectivity of formation of all new bonds without the requirement for any external reagent for asymmetric induction. DFT calculations revealed the formation of furopyrans as the only possible products, which corroborates the experimentally observed results.

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