Hyperbranched polyynes:: Syntheses, photoluminescence, light refraction, thermal curing, metal complexation, pyrolytic ceramization, and soft magnetization

Homopolycouplings of aryltriynes Ar(Cequivalent toCH)(3) and their copolycouplings with monoyne Ar'Cequivalent toCH are effected by CuCl in air under Glaser-Hay oxidative coupling conditions, giving soluble hyperbranched polyynes (hb-PYs). Hyperbranched poly[tris(4-ethynylphenyl)amine] emits bright blue light (lambda = 440 nm) and shows high light refractivity (n = 1.770-1.861). Its peripheral terminal triple bonds can be 100% end-capped by aromatic rings via palladium-catalyzed coupling with aryliodides. The carbon-rich polyynes are readily curable (from similar to150 degreesC), thermally stable (T-d up to -550 degreesC), and pyrolytically carbonizable (W-r up to similar to80% at 900 degreesC). Complexations with cobalt carbonyls metallify the hb-PYs, and ceramizations of the cobalt-polyyne complexes afford soft ferromagnetic materials with high magnetizability (M-s up to similar to118 emu/g) and low coercivity (H-c down to similar to0.045 kOe).