Synthesis and characterization of polyphenylacetylenes with cholesteryl groups in the side chain

Abstract

We have synthesized novel phenylacetylenes with a cholesteryl group at the para position and then polymerized them with a Rh complex catalyst. All polymers were soluble in organic solvents such as toluene, chloroform, and tetrahydrofuran (THF). The monomers obtained showed thermotropic phases, as observed by polarizing optical microscopy and DSC measurements. Their number-average molecular weights determined by GPC with polystyrene standards were in the range of 4.2 × 104 ∼ 7.6 × 104. The high stereoregularity (cis) in the main chain was confirmed by 1H NMR. The backbone π-π * transition of these polymers showed significant specific rotation, indicating an excess of one-handed helical conformations.