Synthesis and two photon absorption of diphenylamino endcapped oligo(9,9-diphenyl)fluorenes with enhanced functional properties

A homologous series of 9,9-diphenyl substituted oligofluorenes end-capped by diphenylamino groups, (Ph)-OF(n)-NPhs, n=1-5, has been synthesized using Suzuki cross coupling reaction as a key step and were fully characterized by H-1 NMR, C-13 NMR, MS, and elemental analyses. The functional properties, including thermal stabilities, linear optical properties, fluorescence and electro-chemical properties, were investigated. The TPA cross sections of these newly synthesized oligofluorenes were measured by the TPF method. Compounds (Ph)-OF(4)-NPh and (Ph)-OF(5)-NPh exhibited larger two-photon absorption cross-sections, about 550 GM and 1390 GM at 800 nm, respectively. (C) 2016 Elsevier B.V. All rights reserved.