Synthesis of long-chain monosaccharides via the coupling of three 'normal' sugar units via Wittig type methodology: Unusual removal of the benzyl group under basic conditions

Article abstract of DOI:10.1016/j.tetasy.2011.10.001

The reaction of diacetonogalactose phosphonate 6 with 2,3:4,5-di-O- isopropylidene-d-arabinose (7) afforded C₁₂-higher sugar enone with an E-geometry across the double bond, which was converted into the fully protected C₁₁-aldehyde 16. This compound was very unreactive and resistant toward the Wittig type and Tebbe reagents, but under PTC conditions, underwent a reaction with stabilized sugar phosphonate to afford C ₁₈-enone 17. Very surprisingly unusual removal of the benzyl blocks under these conditions was observed.