Design and Synthesis of Novel Phenothiazine‐Benzothiadiazine‐1,1‐dioxide Hybrid Organic Material for OLED Applications

Abstract

In this study, yellow thermally activated delayed fluorescence (TADF) emitter PTZ-SA has been designed and synthesized by incorporating phenothiazine as donor and benzothiadiazine-1,1-dioxide as an acceptor. The molecule is also screened for aggregation induced emission in THF/Water system. PTZ-SA shows exceptionally high glass transition temperature (T g ) of 188 °C which clearly highlights good thermal stability of the material. The energy gap (ΔE ST ) between singlet (S1) and triplet (T1) excitons is sufficiently small (0.08 eV) for the reverse intersystem crossing. Yellow electroluminescence peak is observed at 568 nm with Commission Internationale de L'Eclairage coordinates of (0.44, 0.50). The external quantum efficiency of 4.2 % from PTZ-SA is achieved in yellow emitting OLED with turn on voltage of 5.1 V. Moreover, sufficiently high triplet energy of 2.5 eV and good film forming ability of PTZ-SA, encouraged us to study its electro-phosphorescent properties. Nevertheless, the red phosphorescent OLED device incorporating PTZ-SA dopped with a red emitter Ir(piq) 2 acac exhibited maximum external quantum efficiency, power efficiency and luminescence efficiency of 8.1 %, 7.2 lm W À 1 and 5.1 cd A À 1 , respectively.

Polyacetylenes with (hetero)aryl-, styryl-, and amino-phenothiazinyl sidechains: synthesis and photophysics

“…In recent years the venerable electron-rich phenothiazine heterocycles have stimulated increasing scientic interest and have been successfully established in organic electronics, such as organic light-emitting diodes (OLEDs), organic eld-effect transistors (OFETs), dye-sensitized solar cells (DSSCs), molecular wires and organic hole-transport layers. [1][2][3] Due to their low reversible oxidation potential they qualify as good donor molecules, and buttery shaped phenothiazines can be easily oxidized to give stable planar colorful radical cations. 4 The optical and electrochemical properties of phenothiazines can be tuned by introducing substituents in 3-and 7-position using cross-coupling reactions, such as Suzuki and Sonogashira coupling.…”

Exciplex forming a Phenyl-Spaced Phenoxazine D–A Cohost for a Highly Efficient Red-Phosphorescent Organic Light-Emitting Diode

“…Our group has made a fair contribution to the development of bipolar materials for the emissive layer (EML) of OLEDs . By using a reaction scheme consisting of C–C and C–N coupling reactions following classic carbonyl chemistry, we have synthesized pyrroloquinoxaline, , benzothiadiazine-1,1-dioxide, ,, and benzimidazole derivatives as acceptors in π-conjugated bipolar scaffolds. Interestingly, we observed that a rodlike shape of the donor–acceptor (D–A) units in the bipolar molecules proved to be more efficient. , We subsequently synthesized many such molecules with good electroluminescent efficiencies in devices. , The advantages of a rod-shaped design of molecules was twofold.…”

“…10,11 We subsequently synthesized many such molecules with good electroluminescent efficiencies in devices. 8,12 The advantages of a rod-shaped design of molecules was twofold. Intrinsically, a linear design of bipolar materials leads to better conjugation and charge transfer between the D−A units.…”

Synthesis and molecular docking studies of novel tricyclic and angular tetracyclic benzothiadiazines via sp3‐C‐Hactivation as potential colon cancer inhibitors

“…Benzothiadiazines and their derivatives have been established as versatile pharmacological agents [1] and are prevalent in natural products, pharmaceuticals [2], materials [3], and agricultural chemicals [4]. Many of them are in clinical use and trials.…”

“…After the successful preparation of the amino sulfonamide, an appropriate method to cyclize the amine via a C-H sp 3 activation was sought, and a couple of methods were tried to achieve our purpose. The first one was phenyliodine(III) diacetate (PIDA), palladium acetate in the presence of Boc-Ile-OH KOAc, t-BuOH, at 120 C under nitrogen for 24-48 h, which failed to give the required benzothiadiazine [31].…”