Quantitative Structure–Property Relationships for Aryldiazonia

DFT study of electronic properties, structure and spectra of aryl diazonium cations

“…Taking into account such electron correlations by means of MP2 theory, does not improve considerably the results. In contrast, the DFT /B3LYP method is relatively more successful: at high frequencies (P1600 cm À1 ) the overestimation is lower, 100-150 cm À1 , at low frequencies (6300 cm À1 ) the underestimation is even smaller, and at moderate frequencies the overestimation is of about 20-50 cm À1 [10,19]. Earlier calculations of diazonium salts were carried out by the PNDO [20], SCF PPP [21] and CNDO/2 [22] methods, using a fixed geometry.…”

“…It has been argued [10,17,18] that the Hartree-Fock method severely overestimates (by 200-500 cm À1 ) the high frequencies (greater than 1600 cm À1 ), considerably underestimates the low ones (6300 cm À1 ) and systematically overestimates (by 100-200 cm À1 ) the rest ones because of not taking into account electron correlations. Taking into account such electron correlations by means of MP2 theory, does not improve considerably the results.…”

“…For both these reactions, the improvement of the yield depends on the usage of diazonium salts, which lose nitrogen effectively. A measure of diazonium cations stability with respect to the CAN bond cleavage (and at the same time an indicator of their activity as electrophilic agents) can be the frequencies of the stretching vibrations of the CAN"N group [10]. The determination of the corresponding vibrational modes is, therefore, of high importance, however, the low thermal stability of diazonium compounds often prevents extensive IR and Raman spectroscopy experimental studies.…”

املاح الفلزات الانتقالية الأولى للدايازونيوم المشتق من مركب حلقي غير متجانس للنيتروجين تحضيرو تشخيص و الفعالية الحيوية

“…The (C.H.N.) of complex salts were determined, while metal analysis was carried out by using an AAS 240F VARIN instrument, proton NMR signals measured in DMSO-d 6 at room temperature on Varian agillent 500 MHZ spectrometer. The DTG-TGA were measured under dry N2 gas at 1.0 C°/ minute.…”

“…Despite aromatic diazonium salts and metal halide stabilized and well known, little work has been done in the literature 4 5 . Diazonium salts found several applications in different fields such as photo-chemical reactions, analytical chemistry, DNA cleavage , precursors for surface 6,7 , grafting antibacterial and antioxidant 8 .…”