Synthesis of saccharide-terminated poly(ε-caprolactone) via Michael addition and 'click' chemistry

Maleimido-terminated PCL (M-PCL) and alkyne-terrninated PCL (A-PCL) are prepared by the ring-opening polymerization of epsilon-caprolactone with N-hydroxyethyl maleimide and 4-pentyn-1-ol as initiators catalyzed by tin(II) trifluoromethane sulfonate at 25 degrees C, respectively. A series of saccharide-terminated PCLs have also been synthesized under mild conditions by two chemical strategies: 1). Michael addition of M-PCL and amino-containing maltose, and 2). a 'click' reaction of A-PCL and azide-containing saccharide. The amphiphilic nature of these maltose-terminated PCLs make self assembly into aggregates in water possible. These aggregates have been characterized by transmission electron microscopy and dynamic light scattering measurements.