Synthesis and Properties of Symmetrical and Asymmetrical Polyferrocenylmethylenes

Abstract

The synthesis of differently substituted polyferrocenylmethylenes (PFM) via ring-opening transmetalation polymerization (ROTP) is reported. A number of novel, symmetrically and asymmetrically substituted carba[1]magnesocenophanes have been prepared, which were used as precursors and allowed investigations of the influence of different substitution patterns on the PFM polymer properties. The novel carba[1]magnesocenophanes have been fully characterized by ¹H and ¹³C{¹H} NMR spectroscopy, and structurally authenticated by single-crystal X-ray diffraction (SC-XRD). The corresponding PFMs were obtained with molecular weights in a range of M_w=1900 g mol⁻¹ up to 15100 g mol⁻¹ and corresponding dispersities of Đ=1.48 to 1.81. All PFMs have been fully characterized by ¹H and ¹³C{¹H} NMR spectroscopy, as well as by gel permeation chromatography (GPC), thermal gravimetric analysis (TGA) and matrix assisted laser desorption ionization-time-of-flight (MALDI-ToF) mass spectrometry. Pyrolysis of spyrocyclic substituted PFM resulted in a ceramic yield above 50 %, while the obtained residue was characterized by powder X-ray diffraction (PXRD).