Construction of New Azo‐group Containing Polycyclic Imidazole Derivatives: Computational Mechanistic, Structural, and Fluorescence Studies

Abstract

Three polycyclic aromatic imidazole derivatives 2-phenyl-1-(4-(phenyldiazenyl)phenyl)-1H-phenanthro[9,10-d]imidazole (PRO), 2-(4-methoxyphenyl)-1-(4-(phenyldiazenyl)phenyl)-1Hphenanthro[9,10-d]imidazole (PRO1), 2-(2,4-dichlorophenyl)-1-(4-(phenyldiazenyl)phenyl)-1H-phenanthro[9,10-d]imidazole (PRO2) are synthesized with one-pot four component fusion reaction using 1,4-dimethylpyperazinium dihydrosulfate ([Me 2 pi][HSO 4 ] 2 ) ionic liquid (IL) catalyst (3 mol%). Mechanistic studies are performed with DFT M06 L functional. The utilized IL catalyst holds two moles of HSO 4 À per one mole of 1,4-dimethylpyperazinium (cation part), which increases its catalytic performance in a trans form (Figure 1). The IL catalytic effects are determined and described in the optimized transition state structures (Figure 2). Important transition states for the rate-limiting step (~G � = 26.56 kcal/mol), the fivemembered imidazole ring formation (~G � = 6.9 kcal/mol), and the C(sp 3 )-H (~G � = 2.06 kcal/mol) activation are optimized. The PRO fluorescence properties are studied computationally (HOMO and LUMO energy gap = 2.41 eV) and experimentally.

Colorimetric Fluorescence of a 2,4,5‐Triaryl Imidazole‐Based Sensor for the Selective Detection of Iron

“…[24][25][26] Imidazole is a planar five-membered electron-deficient aromatic compound containing two nitrogen atoms with completely different charge properties, one of which is electron-rich and the other electron-deficient. [27][28][29][30][31][32] Attachment of a strong suction or donor group to an imidazole ring causes intramolecular charge transfer (ICT). [33][34][35] Therefore, most of the compounds based on the structure of imidazole have superior luminescence properties.…”

“…Triphenylamine and its derivatives are widely used in the fields of fluorescent materials due to their high triplet energy, good hole transport, strong electron donating properties, as well as strong fluorescence properties and light stability [24–26] . Imidazole is a planar five‐membered electron‐deficient aromatic compound containing two nitrogen atoms with completely different charge properties, one of which is electron‐rich and the other electron‐deficient [27–32] . Attachment of a strong suction or donor group to an imidazole ring causes intramolecular charge transfer (ICT) [33–35] .…”

Computational predictions on Brønsted acidic ionic liquid-catalyzed carbon dioxide conversion to five-membered heterocyclic carbonyl derivatives

“…Ionic liquid (IL)-promoted reactions were utilized in synthetic applications because of the low vapor pressure, high boiling point, recyclability, and low cost of ILs. 23–26…”

“…Ionic liquid (IL)-promoted reactions were utilized in synthetic applications because of the low vapor pressure, high boiling point, recyclability, and low cost of ILs. [23][24][25][26] Density functional theory (DFT) has long been successfully employed to investigate reaction mechanisms. [27][28][29] CO 2 fixation via various homogeneous catalysts has also become a focus of computational scientists.…”

Computational mechanistic studies of the carbon–carbon double bond difunctionalization via epoxidation and subsequent aminolysis in vegetable oils

“…But none of these works comparatively studied experimentally employed oxidizing agents. Computational tools were applied previously for the understanding of reaction mechanisms [20][21][22][23][24][25][26][27]. We chose a model reaction to reduce computational time for the present mechanistic studies: Instead of macromolecular triglyceride, but-2-ene was taken as the internal double bond carrier.…”