Abstract Synthesis of methyl 4, 5-dideoxy-D, L-hex-4-enos-2-ulopyranosid-3-ulose ethylene acetal, derivative of the first natural sugar with dihydropyranone moiety, from 5- acetoxymethylfurfural is described. It was shown that 1, 3-transposition of the allylic alcohol in the dihydropyran ring, a key step of the synthesis, can be carried out via an intermediate allylic selenoxide with excellent regio-and stereoselectivity.
