The reaction of O-isopropylidene pentodialdo-1,4-furanoses with lithium diisopropylamide

Three O-isopropylidene group-protected pentose aldehydes (methyl 2,3-O-isopropylidene-β-d-ribo-pentodialdo-1,4-furanoside (1), methyl 2,3-O-isopropylidene-α-d-lyxo-pentodialdo-1,4-furanoside (2), and 3-O-benzyl-1,2-O-isopropylidene-α-d-xylo-pentodialdo-1,4-furanose (3)) were treated at −30 °C with lithium diisopropylamide (LDA) and the mixtures obtained were reduced with LiAlH4. The products, obtained in moderate yields, proved that deacetonation occurred followed by aldol reactions between aldehydes 1–3 and acetone.