Reaction of Aldonolactones with Hydrogen Bromide

In the heptonolactone series, D-glycero-D-gulo-heptoao-1,4-lactone reacted with hydrogen bromide-acetic acid to afford (44) 2,7-dibromo-2,7-dideoxy-D-g/ycero-D-zWo-heptono-1,4-lactone (35), together with two anhy- 

The bromodeoxyaldonolactones have been used for the preparation of aminodeoxy aldonic acids and aminodeoxy sugars via azido derivatives (45,46). Likewise, a- and /J-aminopolyhydroxy acids have been prepared by treatment of the bromodeoxyaldonolactones with liquid ammonia (47). Thus, 3-amino-3-deoxy-D-threonic acid and 3-amino-3-deoxy-D-arabin-onic acid (40b) were obtained from 2-bromo-2-deoxy-L-threono- or D-xy-lono-1,4-lactone (38). It was shown that 2,3-epoxy carboxamides (namely, 39) are intermediates of the reaction. Heating at 90° for long periods led to the 3-amino-3-deoxyaldonamides, which upon acid hydrolysis yielded the corresponding aldonic acids. 

In the case of the reaction of 2,5-dibromo-2,5-dideoxy-D-xylono- (41a) and D-lyxono-1,4-lactones (41b) with liquid ammonia, the main product 

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The aim of this article is to focus on the diversity of aldonolactones as chiral synthons. The chemistry of aldonolactones was an almost unexplored area when, in 1979, we started our investigations on the reaction of aldonolactones with hydrogen bromide in acetic acid thereby obtaining bromodeoxyaldonolac-tones [1,2]. These compounds have over the years proven to be very versatile compounds for stereoselective synthesis, both in the carbohydrate field, giving access to otherwise less readily obtainable sugars, and as chiral, optically pure synthons in a broader sense within organic chemistry. 

Reaction of Aldonolactones with Hydrogen Bromide in Acetic Acid... 

Oxirans. - The synthesis of l,2-anhydro-3,4-di-0-benzyl-6-deoxy-a-D-glucopyranose and its conformational analysis have been reported. A range of epoxides have been prepared by base treatment of bromohydrins, which were made by reaction of hydrogen bromide with aldonolactones. A one-pot conversion of vicinal diols into epoxides employs halohydrin ester intermediates generated from cyclic orthoacetates and either acetyl bromide or trimethylsilyl chloride. Levoglucosenone has been transformed into l,6 3,4-dianhydro-p-D-talopyranose by way of a trn/w-iodo-acetoxylation of the alkene moiety... 

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