A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, a...A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.展开更多
Diacetates 1 and N-[(1-benzotriazol-l-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) ...Diacetates 1 and N-[(1-benzotriazol-l-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) to afford α,α'-bis(substituted benzylidene) cycloalkanones in good yields.展开更多
A new 2-D Bi（3＋） coordination polymer {Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2}n（1,C7H3NO4 = pyridine-2,6-dicarboxylate） containing（6,5）-connected topological sheet with the Schl？fli symbol of（4~4·6~3·8...A new 2-D Bi（3＋） coordination polymer {Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2}n（1,C7H3NO4 = pyridine-2,6-dicarboxylate） containing（6,5）-connected topological sheet with the Schl？fli symbol of（4~4·6~3·8~4·12~4）（4~5·6~4·8） has been synthesized by an ionothermal method using the ionic liquid 1-ethyl-3-methylimidazolium bromide（[Emim]Br） as solvent,and characterized by C,H and N elemental analysis,energy-dispersive X-ray spectroscopy（EDS）,infrared spectrum（IR spectrum） and single-crystal X-ray diffraction.The results indicate that 1 belongs to the monoclinic system,space group P21/n with a = 13.766（7）,b = 4.142（2）,c = 16.439（8） ？,β = 99.099（9）°,Z = 2,V = 925.6（8） ？~3,Dc = 4.414 g·cm^（-3）,F（000） = 1064,μ = 37.985 mm-1,the final R = 0.0326,wR = 0.0727 and S = 1.022.The molecular structural units [Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2] are connected to each other via bridging O atoms,extending into an interesting 2-D layered structure.These resulting layers are further assembled by weak C-H…O hydrogen bonds into a 3-D supramolecular architecture.Moreover,its thermal stability and the luminescent properties have been also studied.展开更多
a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] a...a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.展开更多
文摘A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.
文摘Diacetates 1 and N-[(1-benzotriazol-l-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) to afford α,α'-bis(substituted benzylidene) cycloalkanones in good yields.
基金Project supported by the National Natural Science Foundation of China(No.21601095)
文摘A new 2-D Bi（3＋） coordination polymer {Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2}n（1,C7H3NO4 = pyridine-2,6-dicarboxylate） containing（6,5）-connected topological sheet with the Schl？fli symbol of（4~4·6~3·8~4·12~4）（4~5·6~4·8） has been synthesized by an ionothermal method using the ionic liquid 1-ethyl-3-methylimidazolium bromide（[Emim]Br） as solvent,and characterized by C,H and N elemental analysis,energy-dispersive X-ray spectroscopy（EDS）,infrared spectrum（IR spectrum） and single-crystal X-ray diffraction.The results indicate that 1 belongs to the monoclinic system,space group P21/n with a = 13.766（7）,b = 4.142（2）,c = 16.439（8） ？,β = 99.099（9）°,Z = 2,V = 925.6（8） ？~3,Dc = 4.414 g·cm^（-3）,F（000） = 1064,μ = 37.985 mm-1,the final R = 0.0326,wR = 0.0727 and S = 1.022.The molecular structural units [Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2] are connected to each other via bridging O atoms,extending into an interesting 2-D layered structure.These resulting layers are further assembled by weak C-H…O hydrogen bonds into a 3-D supramolecular architecture.Moreover,its thermal stability and the luminescent properties have been also studied.
基金supported by the National Natural Science Foundation of China under grant No.20273109.
文摘a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.
