Synthesis and polymerization of 3-oxobornyl methacrylate

The new chiral monomer 3-oxobornyl methacrylate (OBMA) was synthesized from (+)-camphor. Homopolymerization of OBMA and copolymerization of OBMA with styrene were carried out in benzene in the presence of AIBN. The effect of concentration, solvent, temperature, and reaction time on the copolymerization were investigated. It was found that the absolute value of the specific rotation of poly(OBMA-co-St) increased by increasing the OBMA unit content. A small deviation from linearity was observed, which suggests that asymmetry is not introduced into the copolymer main chain. Temperature and solvent effects on the specific rotation of the chiral polymers were investigated. The results suggest that chiral polymers contain no helix conformation. Inspecting the spectra of optical rotatory dispersion and circular dichroism, we found that the chiral polymers exhibit a strong negative Cotton Effect around 310 nm.