Recent advances in the development of phenothiazine and its fluorescent derivatives for optoelectronic applications

Misra, Ranjita; Khan, Faizal

doi:10.1039/d2tc04326b

Cited by 38 publications

(22 citation statements)

References 196 publications

(197 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…SACR-IPTZ exhibits less of a solvatochromic shift than ACR-IPTZ , suggesting a more locally excited (LE) character in the former. Two emission peaks are present for PTZ-IPTZ , likely from the quasi-axial and quasi-equatorial conformers of phenothiazine . A small solvatochromic shift is observed for SMAT-IPTZ due to the reduced reorganization energy in the excited state as a result of structural rigidification, giving blue-shifted emission and a narrower emission band compared to PTZ-IPTZ .…”

Section: Resultsmentioning

confidence: 92%

“…Two emission peaks are present for PTZ-IPTZ, likely from the quasi-axial and quasi-equatorial conformers of phenothiazine. 65 A small solvatochromic shift is observed for SMAT-IPTZ due to the reduced reorganization energy in the excited state as a result of structural rigidification, giving blueshifted emission and a narrower emission band compared to PTZ-IPTZ. Surprisingly, TerCz-IPTZ has very little solvatochromic shift despite dendritic donors having many possible conformations in the excited state, contrasting with the carbon-bridged analogue TerCz-IMAC.…”

Section: ■ Results and Discussionmentioning

confidence: 98%

See 1 more Smart Citation

Imidazophenothiazine-Based Thermally Activated Delayed Fluorescence Materials with Ultra-Long-Lived Excited States for Energy Transfer Photocatalysis

Hojo,

Bergmann,

Elgadi

et al. 2023

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Triplet-triplet energy transfer (EnT) is a powerful activation pathway in photocatalysis that unlocks new organic transformations and improves the sustainability of organic synthesis.Many current examples, however, still rely on platinum-group metal complexes as photosensitizers, with associated high costs and environmental impacts. Photosensitizers that exhibit thermally activated delayed fluorescence (TADF) are attractive fully organic alternatives in EnT photocatalysis. However, TADF photocatalysts incorporating heavy atoms remain rare, despite their utility in inducing efficient spin-orbit-coupling, intersystem-crossing, and consequently a high triplet population. Here, we describe the synthesis of imidazophenothiazine (IPTZ), a sulfur-containing heterocycle with a locked planar structure and a shallow LUMO level. This acceptor is used to prepare seven TADF-active photocatalysts with triplet energies up to 63.9 kcal mol −1 . We show that sulfur incorporation improves spin-orbit coupling and increases triplet lifetimes up to 3.64 ms, while also allowing for tuning of photophysical properties via oxidation at the sulfur atom. These IPTZ materials are applied as photocatalysts in five seminal EnT reactions: [2 + 2] cycloaddition, the disulfide-ene reaction, and Ni-mediated C−O and C−N cross-coupling to afford etherification, esterification, and amination products, outcompeting the industry-standard TADF photocatalyst 2CzPN in four of the five studied scenarios. Detailed photophysical and theoretical studies are used to understand structure−activity relationships and to demonstrate the key role of the heavy atom effect in the design of TADF materials with superior photocatalytic performance.

show abstract

Section: Resultsmentioning

confidence: 92%

Section: ■ Results and Discussionmentioning

confidence: 98%

Imidazophenothiazine-Based Thermally Activated Delayed Fluorescence Materials with Ultra-Long-Lived Excited States for Energy Transfer Photocatalysis

Hojo,

Bergmann,

Elgadi

et al. 2023

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…The heteroarenes molecules are a privileged class of molecules with a diverse range of applications in polymer industries, [37] semiconductor industries, [38] natural products, [39] drug molecules, [40] and optoelectronic applications. [41] The key challenge in constructing the heteroarenes molecules is the homocoupling reaction between both the starting materials which reduces the yield of heterocoupling products. [42] Most of the earlier reported examples for synthesizing the heteroarenes molecules are with simple metal precursors which have product selectivity issues.…”

Section: Decarboxylative Direct Cà H Heteroarylation Of (Hetero)arenesmentioning

confidence: 99%

Mono and Dinuclear Palladium Pincer Complexes of NNSe Ligand as a Catalyst for Decarboxylative Direct C−H Heteroarylation of (Hetero)arenes

Singh,

Shinde,

Kumar

et al. 2023

Chemistry An Asian Journal

View full text Add to dashboard Cite

This report describes the synthesis of a new NNSe pincer ligand and its mono and dinuclear palladium(II) pincer complexes. In the absence of a base, a dinuclear pincer palladium complex (C1) was isolated, while in the presence of an Et3N base a mononuclear palladium pincer complex (C2) was obtained. The new ligand and complexes were characterized using techniques like 1H, 13C{1H} Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared (FTIR), High‐Resolution Mass Spectrometry (HRMS), Ultraviolet–visible (UV‐Visible), and cyclic voltammetry. Both complexes showed pincer coordination mode with a distorted square planar geometry. The complex C1 has two pincer ligands attached through a Pd‐Pd bond in a dinuclear pincer fashion. The air and moisture‐insensitive, thermally robust palladium pincer complexes were used as the catalyst for decarboxylative direct C–H heteroarylation of (hetero)arenes. Among the complexes, dinuclear pincer complex C1 showed better catalytic activity. A variety of (hetero)arenes were successfully activated (48‐87% yield) using only 2.5 mol% of catalyst loading under mild reaction conditions. The PPh3 and Hg poisoning experiments suggested a homogeneous nature of catalysis. A plausible reaction pathway was proposed for the dinuclear palladium pincer complex catalyzed decarboxylative C‐H bond activation reaction of heteroarenes.

show abstract

“…The pioneering work of Tang and Slyke has led to an immense interest in organic luminescent compounds. − In the last three decades, these materials have found their applications in various areas including organic light-emitting devices, − fluorescent probes, , photovoltaics, , electroluminescent materials for organic electronics, and transistor devices. , Among these materials, chalcones exhibiting intramolecular charge transfer (ICT) characteristics have been shown to carry interesting photophysical and photochemical properties . These properties make chalcones particularly interesting, considering the small Stokes shifts of many commonly used fluorescent compounds like fluorescein (24 nm), 5-carboxyfluorescein (36 nm), fluorescein isothiocyanate (24 nm), rhodamine (26 nm), rhodamine 6G (24 nm), Rhodamine Green (26 nm), Cy2 (13 nm), Nile red (70 nm), BODIPY 493 (10 nm), BODIPY 505 (10 nm), MitoTracker Green (26 nm), and MitoTracker Red (20 nm) .…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Photophysical, Electrochemical, and DFT Studies of Piperidyl and Pyrrolidinyl Chalcones

et al. 2023

View full text Add to dashboard Cite

Small organic molecules with interesting optical and electrochemical properties find applications as organic luminescent materials. In this work, we report the synthesis of novel chalcones with D−A−D and D−A−D−A architecture, followed by their optical, electrochemical, and computational studies. The absorption band of these compounds occurs at 360−480 nm with emission maxima appearing around 513−552 nm. The large Stokes shifts (Δλ) for all compounds (90−132 nm) suggest intramolecular charge transfer (ICT) in the excited states. The molar absorptivity and fluorescence quantum yields were found to be in the range of 1.7−4.26 × 10 4 M −1 cm −1 and 0.29−0.39, respectively. The electrochemical parameters were determined by using cyclic voltammetry (CV). Density functional theory (DFT) calculations of all compounds were made by using B3LYP/G (d,p) functionals in chloroform and were found to have a good correlation with experimental results. Preliminary studies of absorption, photoluminescence, CV, and their theoretical correlation suggest that these compounds may be optimized for their applications in optoelectronics, sensing, and bioimaging.

show abstract

Recent advances in the development of phenothiazine and its fluorescent derivatives for optoelectronic applications

Abstract: Phenothiazine is one of the most extensively investigated aromatic compound owing to its unique optical and electronic properties, low cost, and easy functionalization. In recent years, phenothiazine and its derivatives...

Cited by 38 publications

References 196 publications

Imidazophenothiazine-Based Thermally Activated Delayed Fluorescence Materials with Ultra-Long-Lived Excited States for Energy Transfer Photocatalysis

Imidazophenothiazine-Based Thermally Activated Delayed Fluorescence Materials with Ultra-Long-Lived Excited States for Energy Transfer Photocatalysis

Mono and Dinuclear Palladium Pincer Complexes of NNSe Ligand as a Catalyst for Decarboxylative Direct C−H Heteroarylation of (Hetero)arenes

Synthesis and Photophysical, Electrochemical, and DFT Studies of Piperidyl and Pyrrolidinyl Chalcones

Contact Info

Product

Resources

About