부산대학교 도서관

We investigated the polymerization behavior of galactose-based cyclic sulfite as a monomer used to develop the graft polymerization preparation of (1 → 2)-galactan from an alcoholic aglycon. Galactose-based cyclic sulfite 6was prepared from commercially available tri-O-acetyl-D-galactal in 5 steps. Treatment of 6with catalytic (+)-10-camphorsulfonic acid (CSA) in the presence of water as the initiator exhibited ring-opening polycondensation of 6to give benzylated (1 → 2)-galactan and complete elimination of SO2from the main polymer chain. The MALDI-TOF mass spectrum of the obtained polymer showed a simple pattern with even intervals, which suggested formation of benzylated (1 → 2)-galactan with OH groups at both ends. When we used 4-penten-1-ol as the alcohol initiator for polycondensation of 6, we obtained a pentenoyl group-terminated polymer and/or cyclic oligosaccharides. The reaction mechanism for polycondensation of 6was probed through systematic investigations of polymerization and DOSY spectral measurements of the polymer.