Synthesis of A [5] Helicene-Based Chiral Polymer

A copolymer precursor, an alkoxy-functionalized 3,12-diethyenyl [5] helicene, was prepared in seven consecutive steps.A Pd (0)-catalyzed reaction between this helicene derivative and p-diiodo benzene gave polymer 11, which is soluble in many common organic solvents.Peaks in the UV spectrum of 11 are shifted to the red when compared with the spectrum of monomeric analogue 12, presumably because of extended conjugation between the helicene comonomers and the aryl connector units.