Electronic Structure Manipulation of (Benzothiazole)zinc Complexes: Synthesis, Optical and Electrochemical Studies of 5‐Substituted Derivatives

Abstract

The electronic properties of bis[2‐(2‐hydroxyphenyl)benzothiazolato]zinc(II) complexes were tuned by attachment of electron‐withdrawing and ‐donating aryl groups through the Suzuki–Miyaura coupling reaction. Optimization studies of the borylation reaction and Suzuki coupling of protected benzothiazoles were performed to maximize the yields of the target compounds. The absorption, emission, and electrochemical properties of the newly synthesized complexes were found to correlate to the electronic nature of the attached aryl group. Whereas the LUMO levels are less dependent on the substituents, the HOMO levels are very sensitive to the nature of the substituent, thus providing an array of organometallic complexes with gradual changes in redox potentials.

Diaryl‐Substituted Perylene Bis(imides): Synthesis, Separation, Characterization and Comparison of Electrochemical and Optical Properties of 1,7‐ and 1,6‐Regioisomer

“…Suzuki coupling reactions were employed between dibromo‐PBI 2 and aryl‐pinacolborane in a toluene/water biphasic system by using PdCl 2 (dppf) · CH 2 Cl 2 (8 mol‐%) catalyst [dppf = 1,1′‐bis(diphenylphosphanyl)ferrocene] producing PBI derivatives 3 – 7 . Aryl‐pinacolboranes were synthesized by the similar method reported earlier 19a. Even though, presence of steric hindrance in perylene bay region is expected, all the Suzuki couplings gave high yields (75–80 %).…”

Novel ZnII complexes of 2-(2-hydroxyphenyl)benzothiazoles ligands: electroluminescence and application as host materials for phosphorescent organic light-emitting diodes

“…5 In comparison with the phosphorescent Ir and Pt complexes that are usually doped in other matrixes or hosts due to possible triplet-triplet annihilation in neat films and weak charge-transportation ability, the Zn complexes are characterized by the nondoped feature when used as emitters in OLEDs based on their fluorophore nature and electron-transporting capability. [6][7][8][9][10][11][12][13][14][15][16][17][18][19] Research on the application of zinc complexes in OLEDs is mainly focused on designing new and facile ligands. Up to now, several green-, 20 blue-, 16,21 red-, 22 and white 7,13,23 -emitting Zn(II) complexes with various ligands have been developed for OLEDs.…”

“…In the effort to investigate the efficacy of the substituent effect and its possible use in color tuning, some progress has been seen in the preparation of Zn(BTZ) 2 derivatives with substituents on the phenoxide ring. [6][7][8] For example, it was reported 8 that the emission wavelengths of Zn(BTZ) 2 derivatives can be easily tuned from 505 nm to 583 nm by attaching different electronwithdrawing and -donating aryl groups to the 5-position of the phenoxide rings of the ligand. However, it should be noted that few reports have been carried out on Zn(BTZ) 2 derivatives with substituents on the benzothiazole ring so far.…”

Enhanced performance and stability of inverted organic solar cells by using novel zinc-benzothiazole complexes as anode buffer layers

“…In this paper, a series of recently synthesized 5-substituted Znb 2 derivatives (synthesis and photophysical properties described elsewhere 26 ) is investigated as novel buffer layer materials for inverted OSC. A correlation between the chemical-physical characteristics of different Znb 2 complexes and their contribution to the solar cell efficiency is also derived.…”