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.•The newly synthesized organic material compounds (Ph)-OF(n)-NPh have been fully characterized by 1H NMR, 13C NMR, MS, and elemental analyses.•The functional properties, including thermal stabilities, linear optical properties, fluorescence and electro-chemical properties, have been investigated.•The TPA cross sections of these newly synthesized oligofluorenes were measured by the TPF method and 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.

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 1H NMR, 13C 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.

Graphical abstractThe fluorenyl π-system was chosen as TPA material candidates due to its inherently high thermal and photochemical stabilities. we herein describe the synthesis and two-photon absorption properties of a homologues series of chromophores with symmetrical molecular structure of type D-π-D, based on 9,9-diphenyl substituted oligofluorene end-capped with diphenylamino groups acting as an electron donor group (D), (Ph)-OF(n)–NPhs, n = 1–5.Figure optionsDownload full-size imageDownload as PowerPoint slide