Synthesis and Investigation of Thermal, Optical and Electrochemical Properties of 2,4,6‐Trisubstituted Pyrimidines

Abstract

A number of novel fluorophores have been synthesized containing an electron‐withdrawing pyrimidine core and electron donating N,N‐dimethylaminophenyl, 4‐(9H‐carbazol‐9‐yl)phenyl, phenyl and pyrrol‐1‐yl fragments at positions 2, 4 and 6 of the pyrimidine ring. Thermal, optical and electrochemical properties of these substances have been studied. The structure‐property dependences of substituted pyrimidines have been established.

Effect of the Position and Amount of the Electron‐Donating Groups in Substituted 2,4,6‐Triphenylpyrimidines on their Thermal, Optical and Electrochemical Properties

“…If compared to monosubstituted 2,4,6‐triphenylpyrimidine 10 , in case of compound 13 , there is a bathochromic shift of the absorption and emission maxima, a band gap is narrower and absorption capacity – higher (Figure 3). A similar structural dependence of photophysical properties was found in the previous study, devoted to pyrimidines 12 , 13 [29] …”

“…The glass transition temperature of the compound is an important processing parameter at manufacturing of light emitting diodes. If glass transition temperature is too low, the coating can be devitrified at annealing step and, as a result, its integrity can be violated [29] . To control this factor, the thermal characteristics of 2,4,6‐trisubstituted pyrimidines (Figure S11–S16, Supporting Information) were determined by differential scanning calorimetry (DSC) in nitrogen.…”

“…If glass transition temperature is too low, the coating can be devitrified at annealing step and, as a result, its integrity can be violated. [29] To control this factor, the thermal characteristics of 2,4,6-trisubstituted pyrimidines (Figure S11-S16, Supporting Information) were determined by differential scanning calorimetry (DSC) in nitrogen. DSC measurements were carried out at a heating rate of 5 °C/min.…”

“…A similar structural dependence of photophysical properties was found in the previous study, devoted to pyrimidines 12, 13. [29]…”

Synthesis of new D-A-D type fluorophers based on aryl(hetaryl)substituted pyrimidines

“…Для изготовления светоизлучающих диодов важным технологическим параметром является температура стеклования соединения. При низком ее значении при отжиге устройств нанесенное соединение может расстекловываться, что приведет к нарушению целостности покрытия [31] a Eg opt = 1241/λonset; b квантовый выход флуоресценции определен относительно 3-аминофталимида в EtOH, используемого в качестве стандарта (φ = 60%), длина волны возбуждения 370 нм [32] Для 2,4,6-тризамещенного пиримидина 5 наблюдается батохромный сдвиг длин волн максимумов поглощения и испускания в сравнении с пиримидином 4 (рис. 3, 4).…”