A New Route to Hyperbranched Macromolecules:  Syntheses of Photosensitive Poly(aroylarylene)s via 1,3,5-Regioselective Polycyclotrimerization of Bis(aroylacetylene)s

A new synthetic route to hyperbranched polymers is developed. Polycyclotrimerizations of functional diynes 1−3 initiated by a simple base of piperidine lead to the formation of hyperbranched poly(aroylarylene)s P1−P3 with perfect 1,3,5-regioregularity and high degree of branching (up to 100%) in high yields (up to 99%). The polymers show high photosensitivities and can be readily photo-cross-linked to give photoresist patterns with nanometer resolutions.