Achmatowicz oxidative ring expansion 500 -

Conversion of furfuryl alcohol derivatives 48 to pyranones 49 (Achmatowicz oxidative ring expansion) is employed in the synthesis of spiroketal moiety of a natural product and cyclopentenones <00TL6879>. 

The aza-Achmatowicz oxidative ring expansion of furans and its synthetic application were reviewed <1998SL105>. An interesting example of performing the Achmatowicz oxidation of furfuryl alcohol and its aza variant simultaneously on the bisfuran-containing 1,3-amino alcohol 32 in the synthesis of aza-C-linked disaccharides is depicted in Scheme 19 <2005CC1646>. 

Furfuryl alcohols are converted to pyranone derivatives by the Achmatowicz oxidative ring expansion methodology, which is frequently applied in carbohydrate chemistry [28]. Starting from furfiiryl alcohol (X), the following reactions are performed ... 

Dimethoxy-2,5-dihydrofurfuryl alocohl dissolved in 2%-H2S04, and allowed to stand 1.5 hrs. at room temp. 2,3-dideoxy-DL-pent-2-enopyranos-4-ulose. Y ca. 100%. - This is a stage of a multi-step conversion of furan derivs. into monosaccharides. F. e. s. O. Achmatowicz, Jr., et al.. Tetrahedron 27, 1973 (1971) 6-hydroxy-2,6-dihydro-3-pyrones from furylcarbinols by oxidative ring expansion cf. Y. Lefebvre, Tetrah. Let. 1972, 133. 

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