[OldThrashbarg]

Is anyone familiar with this reaction?

[GSR]

hi here is some information from google.

In 1971 Achmatowicz and co-workers described the transformation of furans to sugar derivatives, i.e. the route of obtaining monosaccharides from simple furans compounds. The principle of this method attached. A mixture of cis and trans isomers of the 2,5-dimethoxy-2,5-dihydrofuryl carbinol derivative (A) was hydrolysed by mild acid to cleave the acetal bonds and the resulting dicarbonyl compound (B, not isolated) underwent immediate cyclization to 2,3-dideoxy-DL-alk-2-enopyran-4-ulose (C) (mixture of anomers, if R’ ? R”). Compound C was methylated with methyl orthoformate in the presence of Lewis
acid catalyst, yielding methyl glycosides (D). The reduction of the ketone group in compound D with metal hydrides led to sterioisomeric methyl 2,3-dideoxy-DL-alk-2-enopyranosides (E). Individual steps of the synthesis showed high or satisfactory yields.  This oxidative rearrangement of furyl arbinols to pyranones is now in the literature known as Achmatowicz rearrangement. Two aspects of this synthesis  are noteworthy. Firstly, compounds with the pyranose ring were formed at an early stage in the synthesis, and all steps leading to asymmetric carbon atoms were performed at this ring. Since the stereochemistries of six membered rings are well known, the predictions of the reaction course, as well as the determination of the configuration and conformation of the resulting products are relatively simple. Secondly, the synthesis has the advantage that no more than two stereoisomeric compounds are formed at any stage; usually these can be separated by chromatography. Consequently, the final products can be obtained as pure diastereoisomers. This method for total synthesis of  monosaccharides seems to provide a convenient route for a number of classes of sugar compounds.

[GSR]

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