7394-38-9Relevant academic research and scientific papers
Supramolecular architectures and photoluminescent properties of triethanolammonium 4-nitrobenzoate salt and its Ni(II) complexes
Bourosh, Paulina N.,Crisan, Manuela E.,Croitor, Lilia,Gorobet, Anastasia,Siminel, Anatolii V.
, (2021)
Single crystals of new organic salt (HTEA)(4NB) (1) and its different types of Ni(II) complexes obtained from the same system NiCl2-compound 1 under various experimental conditions: [Ni(4NB)(TEA)(H2O)](4NB) (2), [Ni(4NB)(TEA)(H2O)](4NB)?H2O (3), [Ni(TEA)2](4NB)2 (4) and Ni(BIC)2 (5), where TEA = triethanolammine, 4NB = 4-nitrobenzoate and BIC = N,N-bis(2-hydroxyethyl) glycinate, were successfully synthesized and structural characterized by FTIR spectroscopy and single crystal X-ray analysis. All new compounds represent supramolecular systems assembled by combining two or three organizing forces: metal-coordination (2–5), hydrogen bonds (1–5) and π-π stacking interactions (1–4). In compounds 2 and 3 the Ni(II) atom has an identical NO5 environment, while in complex 4 and 5 the metal centres have a N2O4 coordination core. The ionic coordination complexes 2–4 are arranged into 2D hydrogen-bonding layers and further assembled via π-π stacking interactions in supramolecular 3D network structures, while complex molecules of 5 are organized into a hydrogen-bonded network. This study emphasizes the first structurally characterized binary glycinate Ni(II) complex obtained from NiCl2?6H2O-(HTEA)(4NB) system. Comparative solid-state photoluminescent study of four Ni(II) coordination compounds and initial organic salt reveals a correlation between crystal structure/packing and luminescent properties.
Thermal and kinetics studies of primary, secondary and tertiary alkanolammonium salts of 4-nitrobenzoic acid
Crisan, Manuela,Vlase, Gabriela,Szerb, Elisabeta I.,Vlase, Titus
, p. 1409 - 1418 (2018/02/06)
Nitrobenzoic derivatives are chemically and biologically significant molecules, recently listed as active ingredients in the medical-pharmaceutic field. A series of p-nitrobenzoic acid salts were synthesized with different substituted alkanolamine (ethanolamine, diethanolamine and triethanolamine) via proton exchange reactions and characterized. Fourier transform infrared spectroscopy—FTIR-UATR, and a combination of thermal techniques (differential scanning calorimetry—DSC, and thermogravimetric analysis—TGA) with hot-stage microscopy were used in order to demonstrate the formation of salts and to analyse thermal stability and phase transitions. The aim of this study is to investigate thermal behaviour and kinetics of this class of compounds, previously poorly examined, which offers interesting phase transformations in the solid state. DSC indicated that the synthesized salts had very distinct melting points. Diethanolamine and triethanolamine used as cation in the formation of multicomponent systems with 4-nitrobenzoic acid lead to melting points near 100?°C, compared to compound based on ethanolamine. Calorimetric and thermogravimetric data indicate the absence of solvate forms in all studied compounds. TGA and kinetic experiments allowed the calculation of the activation energy, revealing that triethanolammonium salt has the highest stability in this studied series of compounds.
