CROWNED POLYACETYLENE .1. SYNTHESIS AND CHARACTERIZATION OF POLY(4'-ETHYNYLBENZO-15-CROWN-5)

4'-Ethynylbenzo-15-crown-5 (EB15C5) polymerized with high yields in th e presence of (bicycle[2.2.1] hepta-2,5 -diene)rhodium(I) chloride dim er and triethylamine as a cocatalyst in chloroform at 30 degrees C. Co mmon catalysts for the polymerization of substituted acetylenes, WCl6 and MoCl5, did not produce any polymer from EB15C5. The structure of t he main chain for poly(4'-ethynylbenzo-15-crown-5) (PEB15C5) was deter mined to be predominantly cis form, based upon the relatively sharp si gnals attributed to the main chain atoms that was observed in the H-1 and C-13 NMR spectra. The cation-binding properties of PEB15C5 are ver y similar to that of poly(4'-vinylbenzo-15-crown-5), and the selectivi ty is in the order of K+ > Rb+ much greater than Cs+ <much much greate r than> Na+, Li+. The electrical conductivity of PEB15C5 increased fro m 1.3 X 10(-10) to 1.3 X 10(-6) S . cm(-1), when the polymer was doped with iodine. (C) 1995 John Wiley & Sons, Inc.