Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• File 1). Emission decay on the nanosecond and microsecond timescales was obtained for BPy-pTC, with decay lifetimes of 6.2 ns and 5.8 µs, respectively (Figure 2a as well as Table S6 in Supporting Information File 1). In comparison, a biexponential fluorescence decay with average lifetimes of τavg = 3.5

Substituent effect on TADF properties of 2-modified 4,6-bis(3,6-di-tert-butyl-9-carbazolyl)-5-methylpyrimidines

• Irina Fiodorova,
• Tomas Serevičius,
• Rokas Skaisgiris,
• Saulius Juršėnas and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 497–507, doi:10.3762/bjoc.18.52

• profiles of the DF decay. Unfortunately, TADF decay rates were inaccessible. Similar emission decay transients were also estimated for RTP compounds 2a and 2d both at singlet and triplet emission peaks (see Figure S31 in Supporting Information File 1). The largest DF quantum yield, ranging from 0.34–0.49

Clickable azide-functionalized bromoarylaldehydes – synthesis and photophysical characterization

• Dominik Göbel,
• Marius Friedrich,
• Enno Lork and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2020, 16, 1683–1692, doi:10.3762/bjoc.16.139

• line). d) Time resolved emission decay curves of 5 (in solution, blue dots and in the solid-state, green dots), 42 (in solution, olive dots) and 45 (in solution, red dots) at 25 °C. In all diluted measurements (c = 10−5 mol·L−1) CHCl3 was used as solvent and solutions were sparged with argon for 30

Synthesis and optoelectronic properties of benzoquinone-based donor–acceptor compounds

• Daniel R. Sutherland,
• Nidhi Sharma,
• Georgina M. Rosair,
• Ifor D. W. Samuel,
• Ai-Lan Lee and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2019, 15, 2914–2921, doi:10.3762/bjoc.15.285

• measurements using a combination of TCSPC and MCS techniques (at λPL = 550 nm) revealed two emission decay lifetimes: a prompt component, τp, of 19.4 ns and a very long delayed component, τd, of 352 μs. The two timescales of luminescence are a hallmark of delayed fluorescence behavior (Figure 6). The PL

Pyrene–nucleobase conjugates: synthesis, oligonucleotide binding and confocal bioimaging studies

• Artur Jabłoński,
• Yannic Fritz,
• Hans-Achim Wagenknecht,
• Rafał Czerwieniec,
• Tytus Bernaś,
• Damian Trzybiński,
• Krzysztof Woźniak and
• Konrad Kowalski

Beilstein J. Org. Chem. 2017, 13, 2521–2534, doi:10.3762/bjoc.13.249

• . An X-ray crystal structure analysis of derivative 2 shows dimers stabilized by thymine–thymine hydrogen bonds. Conjugates 2 and 3 with the carbonyl function in the linker moiety are characterized by short emission decay times and low quantum yields. The reduction of the carbonyl function in 2 and 3

Fluorometric recognition of both dihydrogen phosphate and iodide by a new flexible anthracene linked benzimidazolium-based receptor

• Kumaresh Ghosh and
• Debasis Kar

Beilstein J. Org. Chem. 2011, 7, 254–264, doi:10.3762/bjoc.7.34

• fluorescence measurements were additionally carried out to study the dynamics of the flexible receptor 1 (λexc = 369 nm) in the presence and absence of the anions such as H2PO4− in CH3CN. The emission decay profile of 1 monitored at 420 nm could be fitted bi-exponentially with two constants τ1 = 3.42 ns (12.22

Anthracene appended pyridinium amide–urea conjugate in selective fluorometric sensing of L-N-acetylvaline salt

• Kumaresh Ghosh,
• Tanmay Sarkar and
• Asoke P. Chattopadhyay

Beilstein J. Org. Chem. 2010, 6, 1211–1218, doi:10.3762/bjoc.6.139

• band at higher wavelength and this characteristic change distinguishes it from other anionic substrates studied. The binding interaction has been studied by 1H NMR, fluorescence and UV titration experiments. Keywords: N-acetyl-L-valine salt; DFT calculation; emission decay; fluorometric detection

• excitation at 370 nm were then studied to have an insight into the interaction process. The emission decay profile of 1 monitored at 420 nm could be fitted bi-exponential with two constants τ1 = 0.46 ps (100%), τ2 = 2.59 ns (0%). The faster decay component (0.46 ps) is either due to a very short-lived

• emission decay of 2 was monitored at 418 nm in the presence of L-N-acetylvaline salt upon excitation at 370 nm. This observation is thus noteworthy since it distinguishes the L-N-acetylvaline salt in the present study form the others with receptor 1. Concurrently, the ground state binding properties of 1