A Family of BODIPY-like Highly Fluorescent and Unsymmetrical Bis(BF₂) Pyrrolyl–Acylhydrazone Chromophores: BOAPY

Abstract

A new family of pyrrolyl–acylhydrazones anchored with two BF2 units, named BOAPY, have been developed as BODIPY-like and unsymmetrical bis­(BF2) chromophores via a simple one-pot reaction. The easily accessible scaffold enjoys excellent diversity due to the structural versatilities of 2-formylpyrroles and acylhydrazines. BOAPYs exhibit good molar absorption coefficients, large Stokes shifts, and excellent chemical stability. More importantly, most of them display excellent fluorescence quantum yields both in solution and the solid state (up to 0.88 and 0.64, respectively).

Aromatic-Ring-Fused BOPPY Fluorophores: Synthesis, Spectral, Redox Properties, and Bioimaging Application

“…For more than three decades, boron dipyrromethene (BODIPY) dyes, as one of the most successful fluorophores, have been intensively investigated, due to their simple synthesis strategy, easy modification, high stability, and tunable photophysical properties. − The success of BODIPY dyes has inspired investigations into similar skeletal analogue systems, such as Boranil, , aza-BODIPY fluorophore, − and so forth. Recently, bis­(BF 2 ) chromophores containing N–B–N or N–B–O bridges such as BOPHY, − BOIMPY, − BOAPY, and BOPAHY have received much attention, which usually have excellent photostability and exhibit a low LUMO energy level due to the two anchored electron-deficient BF 2 groups (Figure ). Among these, the potential applications of the BOPHY chromophore (Figure ) as a novel platform were immediately established, and its derivatives have been quickly used in a wide array of promising diverse fields from bioimaging and energy-transfer cascades to solar cells and so on.…”

A Family of Highly Fluorescent and Membrane-Permeable Bis(BF2) Acyl-Pyridinylhydrazine Dyes with Strong Solid-State Emission and Large Stokes Shifts: The BOAPH Fluorophores

“…More recently, both Dehaen’s group and our group have disclosed a series of fluorescent and unsymmetrical bis­(BF 2 ) fluorophores, including BOPPY and BOAPY (Figure ), which are highly emissive in solution/solid, and display distinct photostability and large Stokes shift. ,, These new dyes typically adopted much stable and commercially available nonpyrrolic units as starting materials to provide the unsymmetrical structure of the fluorophore core with excellent diversity. Their unique unsymmetrical structures render them favorable photophysical properties such as large Stokes shifts and strong solid-state emission.…”

Recent advances in the synthesis of luminescent tetra-coordinated boron compounds

“…232 Indole-pyridine, hydrazine, pyrrolyl-acylhydrazone, bipyridyl, pyridyl pyrrolide and semihemiporphyrazine based boron compounds were also studied for their tuneable photophysical properties. [237][238][239][240][241][242][243][244][245][246]…”