Chiral Silica with a Helical Structure Formed Using Polymethacrylate-Functionalized Polyhedral Oligomeric Silsesquioxane with Hepta-Cysteine as Template

Chiral silica with a helical structure is generally obtained via sol–gel transcription using a chiral organic surfactant. We propose the use of a polymer that includes a polyhedral oligomeric silsesquioxane side chain, with chiral molecules introduced via covalent bonding, as a template for chiral silica with a helical structure. Here, polymethacrylate-functionalized polyhedral oligomeric silsesquioxane with hepta-vinyl groups (PMAvinylPOSS), which enables the introduction of functional molecules via a postfunctionalization reaction, was prepared using an anionic polymerization method. PMAvinylPOSS was subsequently used to prepare a polymer that contains side chains with chiral segments (designated PMA-CysPOSS) using this postfunctionalization reaction. The resulting helical structure was characterized using electronic circular dichroism (ECD), vibrational circular dichroism (VCD), and circularly polarized luminescence (CPL) measurements. The chiral silica prepared from PMA-CysPOSS as the template was optically active and helical.