Aminonaphthalic Anhydrides as Red-Emitting Materials:  Electroluminescence, Crystal Structure, and Photophysical Properties

Abstract

The red and orange emitters (ANA-1-3) consisting of a 4-amino-1,8-naphthalic anhydride group were synthesized. The lowest absorption band of these ANA molecules centered at approximately 450 nm is assigned to be a charge-transfer transition with emission at 514-536 nm in nonpolar solvents such as n-hexane and at approximately 590-640 nm in polar solvents such as THF and CH(2)Cl(2) and in the solid states. Emission lifetimes are measured with time-correlated single photon counting. Shorter lifetimes are observed for the ANA molecules when dissolved in polar solvents compared with those in nonpolar solvents. Strong dipole-dipole interaction of ANA molecules with solvents is indicated. At high concentrations the measured emission lifetimes, generally shortened from self-quenching, are found to remain about the same order of magnitude in ANAs. This implies that the exciton states of aggregates are formed and they exhibit a relatively long lifetime. Crystallographic data of 4-(phenyl antracen-9-yl) (ANA-2) and 4-(phenyl-2-naphthyl) amino-1,8-naphthalic anhydrides (ANA-3) show that the molecules exist as dimeric structures with antiparallel head-to-tail stacking of naphthalic anhydride planes in addition to other pi-pi stacking. The strong dipole-dipole interactions and the pi-pi stacking account for the observed red-shifted emissions of ANAs in the powders. For films prepared from vacuum sublimation, a structure similar to that in the crystal but with less crystalline order is expected based on the emission wavelength. Several electroluminescent devices based on these ANAs are reported here; they emit orange-red light at 602-628 nm with high brightness and steady external quantum efficiency.

Luminescence Properties of Aminobenzanthrones and Their Application as Host Emitters in Organic Light‐Emitting Devices

“…A similar dependence of the quantum efficiency on the solvent has been observed for 4-amino-1,8-naphthalic anhydride derivatives. [29] The differential scanning calorimetry (DSC) data of these aminobenzanthrone derivatives are also summarized in Table 1. These compounds show melting points (T m ) in the range of 160-383°C and glass-transition points (T g ) between 68 and 158°C.…”

Investigation on the optical, mechanical and magnetic properties of organic NLO single crystal: Pyridine 3-carboxylic acid

“…The red emission owing to polar environment and π to π stacking. The Materials contain an aromatic functional group of low energy (π to π * ) transition levels show high and intense fluorescence behaviour [26][27]. There are two energy transition mechanism adopted from the donor to the acceptor.…”

A New Orange-Light-Emitting Materials Based on (N-naphthyl)-1,8-naphthalimide for OLED Applications

“…(N-naphthyl)-4-diphenylamino-1,8-naphthalimide (NBID-1) [14], To a 100 mL three-necked flask under nitrogen were added (a) (1.00 g, 2.5 mmol), diphenylamine (0.70 g, 3.0 mmol), Pd(OAc) 2 (0.07 g, 0.10 mmol), tri-tert-butyl phosphine (0.01 g, 0.04 mmol), and sodium tert-butoxide (0.36 g, 3.70 mmol). Toluene (10 mL) was then added to the flask via a syringe and the mixture was stirred for 24 h at 120 C. After completion of the reaction, resulting mixture was cooled and poured into water.…”