Published online by Cambridge University Press: 25 February 2011
1-Phenyl-l,3-butadiyne derivatives (3 and 4) carrying stable t-butylnitroxide and diazomethyl groups, respectively, have been prepared. Mixed crystals of 3 and the corresponding hydroxylamine 2 (x003c:1:1) polymerized in the solid state at 100°C to give black-violet microcrystals with a metallic luster. A microcrystalline sample of 4 underwent spontaneous polymerization at room temperature when crystallized to give an insoluble polymer which was then photolyzed at cryogenic temperature to generate triplet carbene centers attached to the phenyl rings of the poly(phenyldiacetylene). Some of these microcrystalline polymeric samples were responsive to a magnet at room temperature. Magnetic susceptibility measurements on the two samples revealed only weakly coupled independent spins Hydrogen bonding between the polydiacetylene chains as estimated by X-ray crystal structure of 2 is expected to be effective for increasing the dimension of the spin alignment.