Intramolecular charge-transfer interactions in a julolidine–Bodipy molecular assembly as revealed via 13C NMR chemical shifts

Benniston, Andrew C.; Clift, Sophie; Harriman, Anthony

doi:10.1016/j.molstruc.2010.11.018

Cited by 24 publications

(21 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The broad spectral profile accounts for about 70 % of the total spectrum at room temperature. It is known [39] that the emission peak for many exciplexes, including Bodipy-derived species, [40] moves to lower energy as the solvent polarity, usually expressed [41] in terms of the static dielectric constant (e S ), increases. Notably, the band maximum for the locally excited fluorescence remains fixed whereas that for the broad profile moves steadily to the red as the fluid solution is cooled.…”

Section: Synthesis and Energeticsmentioning

confidence: 99%

“…[38] On the basis of the electrochemistry, the broad, featureless fluorescence spectral profile appears consistent with formation of an emissive exciplex by way of partial charge transfer from the Bodipy excited state to the appended dicyanovinyl unit. It is known [39] that the emission peak for many exciplexes, including Bodipy-derived species, [40] moves to lower energy as the solvent polarity, usually expressed [41] in terms of the static dielectric constant (e S ), increases. Such behavior explains the temperature dependence observed for BOD-DCV in fluid MTHF (e S = 6.24) and in diethyl ether (e S = 4.34).…”

Section: Synthesis and Energeticsmentioning

confidence: 99%

See 1 more Smart Citation

Exciplex Emission from a Boron Dipyrromethene (Bodipy) Dye Equipped with a Dicyanovinyl Appendage

et al. 2013

Self Cite

View full text Add to dashboard Cite

The photophysical properties of a prototypic donor-acceptor dyad, featuring a conventional boron dipyrromethene (Bodipy) dye linked to a dicyanovinyl unit through a meso-phenylene ring, have been recorded in weakly polar solvents. The absorption spectrum remains unperturbed relative to that of the parent Bodipy dye but the fluorescence is extensively quenched. At room temperature, the emission spectrum comprises roughly equal contributions from the regular π, π* excited-singlet state and from an exciplex formed by partial charge transfer from Bodipy to the dicyanovinyl residue. This mixture moves progressively in favor of the locally excited π, π* state on cooling and the exciplex is no longer seen in frozen media; the overall emission quantum yield changes dramatically near the freezing point of the solvent. The exciplex, which has a lifetime of approximately 1 ns at room temperature, can also be seen by transient absorption spectroscopy, in which it decays to form the locally excited triplet state. Under applied pressure (P<170 MPa), formation of the exciplex is somewhat hindered by restricted rotation around the semirigid linkage and again the emission profile shifts in favor of the π, π* excited state. At higher pressure (170

show abstract

Section: Synthesis and Energeticsmentioning

confidence: 99%

Section: Synthesis and Energeticsmentioning

confidence: 99%

Exciplex Emission from a Boron Dipyrromethene (Bodipy) Dye Equipped with a Dicyanovinyl Appendage

et al. 2013

Self Cite

View full text Add to dashboard Cite

show abstract

“…Deconvolution of the absorption spectrum into a series of Gaussian bands (see the Supporting Information) shows that the introduction of styryl units to JULBD1 strongly shifts the S 0 →S 1 electronic transition by 144 nm, but the CT band remains mostly unaffected, as compared to the parent unsubstituted julolidyl BODIPY . The simple explanation is that extending the conjugation raises the energy of the BODIPY‐centred HOMO‐1 whilst the julolidine centred HOMO is not affected, thus the redshift in absorption maximum is more pronounced for the BODIPY transition HOMO‐1→LUMO.…”

Section: Resultsmentioning

confidence: 99%

“…Our first rudimentary model dyad system, based on a julolidyl donor linked to an unsubstituted BF 2 ‐dipyrromethene subunit, showed exceptionally strong CT character . The charge density distribution within the dyad was evident by a solvent effect, and 13 C NMR chemical shifts could be fitted adequately to a polarity model . Although the electrical firing of neurons in crab stomatogastric ganglions (STG) could be monitored by a fluorescence intensity modulation, the changes were still rather modest.…”

Section: Introductionmentioning

confidence: 97%

Locally Excited State–Charge Transfer State Coupled Dyes as Optically Responsive Neuron Firing Probes

Sirbu

Butcher

Waddell

et al. 2017

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

A selection of NIR-optically responsive neuron probes was produced comprising of a donor julolidyl group connected to a BODIPY core and several different styryl and vinylpyridinyl derived acceptor moieties. The strength of the donor-acceptor interaction was systematically modulated by altering the electron withdrawing nature of the aryl unit. The fluorescence quantum yield was observed to decrease as the electron withdrawing effect of the aryl subunit increased in line with changes of the Hammett parameter. The effectiveness of these fluorophores as optically responsive dyes for neuronal imaging was assessed by measuring the toxicity and signal-to-noise ratio (SNR) of each dye. A great improvement of SNR was obtained when compared to the first-generation BODIPY-based voltage sensitive dyes with concomitant toxicity decrease. The mechanism for the optical response is disparate from conventional cyanine-based dyes, opening up a new way to produce effective voltage sensitive dyes that respond well into the NIR region.

show abstract

“…Nevertheless, the same dye was used as donor and acceptor; further studies were conducted using others dyes such as anthracene [9], hydroquinone [10,11], julolidine [12] and dicyanovinyl [13] in which the effect of the electrochemical potential in the transfer rates was measured. During those studies, it was found that the bridging unit plays a key role in the transfer rates, in particular in the recombination to the ground state.…”

Section: Small Dyad Systemsmentioning

confidence: 99%

Recent advances in artificial photosynthetic systems at Newcastle University

Farràs

Cucinotta

2017

Comptes Rendus Chimie

View full text Add to dashboard Cite

This review covers the most significant research done by the grouping of scientists working at Newcastle University during the last five years in the area of artificial photosynthesis. In particular, it tackles aspects of light harvesting in molecular systems and solid state materials, photocatalysis in homogeneous and heterogenous phase, and the fabrication of photoelectrochemical devices for the generation of hydrogen.

show abstract

Intramolecular charge-transfer interactions in a julolidine–Bodipy molecular assembly as revealed via 13C NMR chemical shifts

Cited by 24 publications

References 69 publications

Exciplex Emission from a Boron Dipyrromethene (Bodipy) Dye Equipped with a Dicyanovinyl Appendage

Exciplex Emission from a Boron Dipyrromethene (Bodipy) Dye Equipped with a Dicyanovinyl Appendage

Locally Excited State–Charge Transfer State Coupled Dyes as Optically Responsive Neuron Firing Probes

Recent advances in artificial photosynthetic systems at Newcastle University

Contact Info

Product

Resources

About