Iodine(III)-Promoted Azide Transfer to 3-Deoxyglycals

Abstract

Direct iodine(III) promoted azide-transfer to 3-deoxyglycals 1-4 is described, leading to azidoglycals 5a,b-7a,b and hex-2-enopyranosyl azides 8a,b as main products. For the synthesis of precursor 1,5-anhydro-2,3,6-trideoxy-L-threo-hex-1-enitol (L-rhodinal) 3 a new high yielding synthetic variant of the literature is presented. The configuration of the new stereogenic center in 7a,b is determined by comparison of coupling constants with azidoglycal 15 which is obtained by a new synthesis employing a variant of the Mitsunobu reaction.