Poly（arylene ethynylene）s,P1 and P2 containing 1,3,5-triazine and chalcone unites respectively,were synthesized by Sonogashira coupling reaction.These polymers exhibited good solubility in common organic solvents,such as dichloromethane,chloroform,and tetrahydrofuran.The molecular weight Mw of P1 was 6390 with polydispersity（PDI） being 2.33 and that of P2 was 6870 with polydispersity（PDI） being 1.85 characterized by GPC.The photophysical properties were analyzed by solution and solid state photoluminescence spectroscopy.P1 emitted blue fluorescence at around 441 nm in CH2Cl2 or THF solutions under UV excitation.The photoluminescence behavior of P2 was dependent on the solvent,with green emitting light at around 550 in CH2Cl2 solution and 500 nm in THF solution.Powder photoluminescence spectra of P1 and P2 showed that the peak wavelengths respectively shifted to 530 and 605 nm.
One\|pot”reaction of 1,3,5 tribromobenzene with nonylmagnesium bromide,prepared by 1\|bromononane with magnesium in THF,catalyzed by Ni(PPh\-3)\-2Cl\-2,was used to obtain hyperbranched polyphenylene 1.The macromolecule was characterized by GPC with molecular weight M n=4247 and polydispersity PD =1 36.Under the conditin of Heck reaction catalyzed by palladium\|complexes,the terminal bromine groups on this macromolecule coupled with styrene and phenylacetylene,respectively,to provide correspondign hyperbranched polyphenylene 2 and 3 with stilbenyl and diphenylacetyl fluorophores on their surface.These two polymers both exhibited two bands E\-1 and E\-2 at near 260 nm and 300 nm in their UV spectra.In their powder photoluminescence spectra,the maximum emitting peaks at 401 nm and 386 nm in the range of blue luminescence were observed,respectively.
Polyphenylene dendrimers 11,12 and 13 containing terminal trimethylsilyl groups have been synthesized by phosphine-free palladium chloride catalyzed Suzuki couplings of 1,3,5-tris(3′,5′-dibromophenyl)benzene 9 with aryl boronic acids 5 and 6.These macromolecules were characterized by Fourier transform infrared (FTIR),nuclear magnetic resonance (NMR) and matrix assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectra.Gel permeation chromatograph (GPC) indicated that the hydrodynamic radium of 12,with trimethylsiliyl (—TMS) groups substituted at para-positions on its terminal benzene rings,was larger than that of 13,with trimethylsiliyl groups substituted at meta-positions on its terminal benzene rings.X-ray powder diffraction patterns showed that dendrimer 12 was of a certain amount of crystallinity and dendrimer 13 was amorphous.
