Synthesis and application of Vis/NIR dialkylaminophenylbuta-1,3-dienyl borondipyrromethene dyes

Mono- and bis-dialkylaminophenylbuta-1,3-dienyl boron-dipyrromethenes (BODIPYs) 1–12 were synthesized in 36%–42% yields by a Knoevenagel-type condensation. The absorption and emission maxima (λabs = 614–739 nm; λem = 655–776 nm in CHCl3) of 1–12 covered from the visible to the near-infrared region. Probe 1 was ratiometric Vis pH probes. Such probe was almost non-fluorescent. Upon the protonation of the tertiary amine function of 1, the strong fluorescence (Φf = 0.97) was released and the florescence intensity was dramatically increased by one thousand folds. The sharp isosbestic points were discovered at 590 nm, which was a ratiometric pH probe.

Mono- and bis-dialkylaminophenylbuta-1,3-dienyl BODIPYs 1–12 (λabs = 614–739 nm; λem = 655–776 nm in CHCl3) were synthesized by a Knoevenagel-type condensation. Upon the protonation of the tertiary amine function of 1 as a pH probe, the strong fluorescence (Φf = 0.97) was released and the florescence intensity was dramatically increased by one thousand folds.Figure optionsDownload as PowerPoint slide