We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of d...We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of durability and the probability of their formation. We performed the light fastness calculations of the monoazopyridone dyes. Using the semi-empirical methods of quantum chemistry AM1 and PM3, the reactivity indicators of superdelocalisability (SrE(N)) and the electron density distribution in ground state on the highest occupied HOMO orbital and the lowest unoccupied excited state LUMO in 2-pyridone phenylazo derivatives were calculated. Superdelocalisability coefficients enable the stability to oxidising agents of various chemical molecules depending on the tautomeric forms in which they may occur. The results of the electron density calculations at the HOMO and LUMO boundary orbitals allow to determine the tendency to electrophilic attack with singlet oxygen 1O2 or nucleophilic attack of the superoxide anion O2•−on a specific atom in the molecule. The structure of the dyes was optimised with MM+, MD and AM1 or PM3 until a constant energy value was achieved with a convergence criterion of 0.01 kcal/mol.展开更多
Electronic structures of monoclinic and hexagonal pyrrhotite were studied using density functional theory method,together with their flotation behavior. The main contribution of monoclinic pyrrhotite is mainly from Fe...Electronic structures of monoclinic and hexagonal pyrrhotite were studied using density functional theory method,together with their flotation behavior. The main contribution of monoclinic pyrrhotite is mainly from Fe 3d, while that of hexagonal pyrrhotite is from Fe 3d, Fe 3p and S 3s. The hexagonal pyrrhotite is more reactive than monoclinic pyrrhotite because of large density of states near the Fermi level. The hexagonal pyrrhotite shows antiferromagnetism. S—Fe bonds mainly exist in monoclinic pyrrhotite as the covalent bonds, while hexagonal pyrrhotite has no covalency. The main contributions of higest occupied molecular orbital(HOMO) and lowest unoccupied molecular obital(LUMO) for monoclinic pyrrhotite come from S and Fe. The main contribution of HOMO for hexagonal pyrrhotite comes from Fe, while that of LUMO comes from S. The coefficient of Fe atom is much larger than that of S atom of HOMO for hexagonal pyrrhotite, which contributes to the adsorption of Ca OH+ on the surface of hexagonal pyrrhotite when there is lime. As a result, lime has the inhibitory effect on the floatation of hexagonal pyrrhotite and the coefficient of Fe is very close to that of S for monoclinic pyrrhotite. Therefore, the existence of S prevents the adsorption of Ca OH+on the surface of monoclinic pyrrhotite, which leads to less inhibitory effect on the flotation of monoclinic pyrrhotite.展开更多
The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and indoles.Hydroxybenzyl alcohols,aminoben...The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and indoles.Hydroxybenzyl alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid conditions.The relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,8-additions.Moreover,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative additions.The conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past decade.This review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.展开更多
An optimized compound 9-(9,9-dimethylacridin-10(9 H)-yl)-6 H-benzo[c]ch-romen-6-one(MAB) was designed and synthesized based on our previously reported TADF emitter 6-(9,9-dimethylacridin-10(9 H)-yl)-3-methyl-1 H-isoch...An optimized compound 9-(9,9-dimethylacridin-10(9 H)-yl)-6 H-benzo[c]ch-romen-6-one(MAB) was designed and synthesized based on our previously reported TADF emitter 6-(9,9-dimethylacridin-10(9 H)-yl)-3-methyl-1 H-isochromen-1-one(MAC) to further improve the performance of thermally activated delayed fluorescence(TADF)emitters. With the additional phenyl in coumarin-contained plane, MAB possesses an extended distribution of the lowest unoccupied molecular orbitals(LUMO), and thus realizes reduced electron exchange between the frontier molecular orbitals and a stretched molecular dipole moment compared with MAC. MAB based organic light-emitting diode(OLED)exhibits a remarkable maximum external quantum efficiency(EQE) of 21.7%, which is much better than the maximum EQE of MAC-based OLED with a value of 12.8%. Our work proves that extending the distribution of LUMO is a simple but effective method to improve the efficiency of TADF emitter.展开更多
The molecular structure, the Natural Bond orbital (NBO) and the Time Dependent-DFT of both isomers cis or γ-Cl and trans or δ-Cl of RuCl2(L)2, where L stands respectively for 2-phenylazopyridine (Azpy), 2,4-dimethyl...The molecular structure, the Natural Bond orbital (NBO) and the Time Dependent-DFT of both isomers cis or γ-Cl and trans or δ-Cl of RuCl2(L)2, where L stands respectively for 2-phenylazopyridine (Azpy), 2,4-dimethyl-6-[phenylazo]pyridine (Dazpy), 2-[(3,5-dimethylphenyl)azopyridine] (Mazpy) and 2-pyridylazonaphtol (Nazpy) were calculated with DFT method at B3LYP/LANL2DZ level. The prediction of the frontier orbitals (Highest Occupied Molecular Orbital or HOMO and Lowest Unoccupied Molecular Orbital or LUMO) shows that the most active complexes suitable for electronic reactions are admitted to be the trans isomers. Moreover, δ-RuCl2 (Azpy)2 is discovered to react more actively as photo-sensitizer since its energy gap is the minimum. Besides, electronic structures of all complexes through NBO calculation indicate that Ru-N bonds are made of delocalization of occupancies from lone pair orbital of N atoms to the ruthenium. Moreover, Ru was assumed to have almost the same charge regardless the structure of the azopyridine ligands in the complex indicating that the ligands provide only a steric effect that is responsible for the ruthenium’s selectivity. Concerning the transition state, NBO analysis also highlights that the transition LP(Ru) π*(N1-N2) does correspond to t2g?π*(L). This transition is assumed to correspond to Metal to Ligand Charge Transfer (MLCT) that is responsible for the photo-sensitiveness of the metallic complex. Besides, TDDFT calculation of complexes showed that δ-RuCl2(Nazpy)2 displays the largest band during the absorption. For that reason, it is admitted to be the best photosensitizer due to a large system of conjugation provided by Nazpy ligand.展开更多
The AM1 and B3LYP methods were employed to calculate the structural properties of 20 6-(1-naphthylmethyl) substituted S-DABO derivatives with β-carbonyl group on the C(2) side chain as novel potent non-nucleoside...The AM1 and B3LYP methods were employed to calculate the structural properties of 20 6-(1-naphthylmethyl) substituted S-DABO derivatives with β-carbonyl group on the C(2) side chain as novel potent non-nucleoside HIV-1 reverse transcriptase inhibitors. The correlation analysis (CA) and stepwise multiple regression analysis (SMR) were performed. The QSAR models indicate that the physicochemical parameters of Qc9, MRR1, ELUMO, ∏R2 and μ have significant influence on the activities of these derivatives. The substitution of hydrophobic R2 and bulky aromatic R1 to form a conjugated system with the frame of those S-DABO series compounds should be considered to design new potent compounds for anti-HIV-1.展开更多
A novel air-stable n-type benzothiaphene endcapped azaarene(BTPQ) and its sulfonated derivative(BSPQ) were prepared via two pathways and characterized by NMR, UV–vis, fluorescence and cyclic voltammetry spectroscopy....A novel air-stable n-type benzothiaphene endcapped azaarene(BTPQ) and its sulfonated derivative(BSPQ) were prepared via two pathways and characterized by NMR, UV–vis, fluorescence and cyclic voltammetry spectroscopy. Symmetrically introducing four nitrogen atoms into acenes, the semiconductor properties could be changed from p-type to n-type detected through the space charge limited current(SCLC) method. After sulfonation of BTPQ, BSPQ is with deeper frontier orbital energy levels and enhanced the electron mobility.展开更多
A novel organic electron acceptor, N,N′-dipyrimidinyl-3,4,9,10-perylene-tetracarboxylic diimide (DMP), was designed and synthesized. The molecular structure was characterized by FTIR spectrum and elemental analysis. ...A novel organic electron acceptor, N,N′-dipyrimidinyl-3,4,9,10-perylene-tetracarboxylic diimide (DMP), was designed and synthesized. The molecular structure was characterized by FTIR spectrum and elemental analysis. By cyclic voltammetry measurements, DMP was found to possess a lower LUMO energy level than N,N′-diphenyl-3,4,9,10-perylene-tetracarboxylic diimide due to the stronger electron-withdrawing pyrimidinyl group than the phenyl group. Fluorescence quenching is observed in a dual-layer film consisting of a DMP layer and a C60 layer and was attributed to the charge transfer at the interface due to the energy level offset between DMP and C60.展开更多
Density functional theory (DFT) calculations were carried out on the compounds Cp2Ln-guan for Ln=Y, Lu, Yb, Dy and Gd, [guan=(iPrN)2CN(iPr)2]. The results were compared with the X-ray structures that were available fr...Density functional theory (DFT) calculations were carried out on the compounds Cp2Ln-guan for Ln=Y, Lu, Yb, Dy and Gd, [guan=(iPrN)2CN(iPr)2]. The results were compared with the X-ray structures that were available from the literature; the calculations reproduced quite well the experimental structural features in these complexes exhibiting distorted tetrahedron geometry. The calculated evolution of the Ln-guan bond as a function of the cation showed that lanthanide-ligand distances increased with the increa...展开更多
Two amphiphilic barbituric acid derivatives with a D-π-A structure, 5-(4-dodecyloxybenzylidene)-(1H,3H)-2,4,6-pyrimidinetrione(PB_ 12) and 5-(4-N,N-didodecylaminobenzylidene)-(1H,3H)-2,4,6-pyrimidintrione(AB_ 12) w...Two amphiphilic barbituric acid derivatives with a D-π-A structure, 5-(4-dodecyloxybenzylidene)-(1H,3H)-2,4,6-pyrimidinetrione(PB_ 12) and 5-(4-N,N-didodecylaminobenzylidene)-(1H,3H)-2,4,6-pyrimidintrione(AB_ 12) were found to show different aggregation behavior in chloroform. PB_ 12, a derivative with weak electron donating and strong electron drawing substituents, tends to aggregate in a head-to-tail manner, whereas AB_ 12, a derivative with both strong electron donating and drawing substituents, tends to aggregate in a face-to-face manner at a higher concentration. The cyclic voltammograms of AB_ 12 and PB_ 12 show that their energy levels of LUMO approach each other, however, the energy level of HOMO of AB_ 12 is much higher than that of PB_ 12.展开更多
The structural properties and vibrational frequencies of 2-phenyl-2-imidazoline have been investigated using theoretical and techniques by which a good correlation was observed. The assignments of the vibrational mode...The structural properties and vibrational frequencies of 2-phenyl-2-imidazoline have been investigated using theoretical and techniques by which a good correlation was observed. The assignments of the vibrational modes were performed with the help of normal co-ordinate analysis following the Scaled Quantum Mechanical Force Field methodology. Natural bond orbital analysis and the highest occupied molecular orbital-lowest unoccupied molecular orbital gap analysis have been carried out. UV-visible spectrum of the compound was recorded and compared with the theoretical UV-visible spectrum of the title molecule using Symmetry Adapted Cluster-Configuration Interaction method which yielded good agreement. Our results reflect that the title compound can be used as good source of UV light.展开更多
文摘We analysed the photooxidation reaction in the electro-(1O2) and nucleophilic (O2•−) reaction of 2-pyridone azo derivatives. First, we calculated the energy (enthalpies) of tautomers formation, which is a measure of durability and the probability of their formation. We performed the light fastness calculations of the monoazopyridone dyes. Using the semi-empirical methods of quantum chemistry AM1 and PM3, the reactivity indicators of superdelocalisability (SrE(N)) and the electron density distribution in ground state on the highest occupied HOMO orbital and the lowest unoccupied excited state LUMO in 2-pyridone phenylazo derivatives were calculated. Superdelocalisability coefficients enable the stability to oxidising agents of various chemical molecules depending on the tautomeric forms in which they may occur. The results of the electron density calculations at the HOMO and LUMO boundary orbitals allow to determine the tendency to electrophilic attack with singlet oxygen 1O2 or nucleophilic attack of the superoxide anion O2•−on a specific atom in the molecule. The structure of the dyes was optimised with MM+, MD and AM1 or PM3 until a constant energy value was achieved with a convergence criterion of 0.01 kcal/mol.
基金Project supported by the Open Foundation of Guangxi Key Laboratory for Advanced Materials and Manufacturing Technology,China
文摘Electronic structures of monoclinic and hexagonal pyrrhotite were studied using density functional theory method,together with their flotation behavior. The main contribution of monoclinic pyrrhotite is mainly from Fe 3d, while that of hexagonal pyrrhotite is from Fe 3d, Fe 3p and S 3s. The hexagonal pyrrhotite is more reactive than monoclinic pyrrhotite because of large density of states near the Fermi level. The hexagonal pyrrhotite shows antiferromagnetism. S—Fe bonds mainly exist in monoclinic pyrrhotite as the covalent bonds, while hexagonal pyrrhotite has no covalency. The main contributions of higest occupied molecular orbital(HOMO) and lowest unoccupied molecular obital(LUMO) for monoclinic pyrrhotite come from S and Fe. The main contribution of HOMO for hexagonal pyrrhotite comes from Fe, while that of LUMO comes from S. The coefficient of Fe atom is much larger than that of S atom of HOMO for hexagonal pyrrhotite, which contributes to the adsorption of Ca OH+ on the surface of hexagonal pyrrhotite when there is lime. As a result, lime has the inhibitory effect on the floatation of hexagonal pyrrhotite and the coefficient of Fe is very close to that of S for monoclinic pyrrhotite. Therefore, the existence of S prevents the adsorption of Ca OH+on the surface of monoclinic pyrrhotite, which leads to less inhibitory effect on the flotation of monoclinic pyrrhotite.
基金the financial support from the National Natural Science Foundation of China(No.22001216)the Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province(No.CSPC202315)+2 种基金the Science and Technology Department of Sichuan Province,China(No.2022NSFSC1203)the Higher Education Institution Key Research Project Plan of Henan Province(No.24B150031)the Program for Youth Backbone Teacher Training in University of Henan Province(No.2021GGJS163)。
文摘The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and indoles.Hydroxybenzyl alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid conditions.The relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,8-additions.Moreover,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative additions.The conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past decade.This review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs.
基金supported by the National Natural Science Foundation of China (51773029, 51533005 and 51373190)the National Key Research & Development Program of China (2016YFB0401002)+1 种基金Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the 111 Project and Qing Lan Project, China
文摘An optimized compound 9-(9,9-dimethylacridin-10(9 H)-yl)-6 H-benzo[c]ch-romen-6-one(MAB) was designed and synthesized based on our previously reported TADF emitter 6-(9,9-dimethylacridin-10(9 H)-yl)-3-methyl-1 H-isochromen-1-one(MAC) to further improve the performance of thermally activated delayed fluorescence(TADF)emitters. With the additional phenyl in coumarin-contained plane, MAB possesses an extended distribution of the lowest unoccupied molecular orbitals(LUMO), and thus realizes reduced electron exchange between the frontier molecular orbitals and a stretched molecular dipole moment compared with MAC. MAB based organic light-emitting diode(OLED)exhibits a remarkable maximum external quantum efficiency(EQE) of 21.7%, which is much better than the maximum EQE of MAC-based OLED with a value of 12.8%. Our work proves that extending the distribution of LUMO is a simple but effective method to improve the efficiency of TADF emitter.
文摘The molecular structure, the Natural Bond orbital (NBO) and the Time Dependent-DFT of both isomers cis or γ-Cl and trans or δ-Cl of RuCl2(L)2, where L stands respectively for 2-phenylazopyridine (Azpy), 2,4-dimethyl-6-[phenylazo]pyridine (Dazpy), 2-[(3,5-dimethylphenyl)azopyridine] (Mazpy) and 2-pyridylazonaphtol (Nazpy) were calculated with DFT method at B3LYP/LANL2DZ level. The prediction of the frontier orbitals (Highest Occupied Molecular Orbital or HOMO and Lowest Unoccupied Molecular Orbital or LUMO) shows that the most active complexes suitable for electronic reactions are admitted to be the trans isomers. Moreover, δ-RuCl2 (Azpy)2 is discovered to react more actively as photo-sensitizer since its energy gap is the minimum. Besides, electronic structures of all complexes through NBO calculation indicate that Ru-N bonds are made of delocalization of occupancies from lone pair orbital of N atoms to the ruthenium. Moreover, Ru was assumed to have almost the same charge regardless the structure of the azopyridine ligands in the complex indicating that the ligands provide only a steric effect that is responsible for the ruthenium’s selectivity. Concerning the transition state, NBO analysis also highlights that the transition LP(Ru) π*(N1-N2) does correspond to t2g?π*(L). This transition is assumed to correspond to Metal to Ligand Charge Transfer (MLCT) that is responsible for the photo-sensitiveness of the metallic complex. Besides, TDDFT calculation of complexes showed that δ-RuCl2(Nazpy)2 displays the largest band during the absorption. For that reason, it is admitted to be the best photosensitizer due to a large system of conjugation provided by Nazpy ligand.
基金NNSFC(20563005)partially supported by Center for Advanced Studies of Medicinal and Organic Chemistry of Yunnan University
文摘The AM1 and B3LYP methods were employed to calculate the structural properties of 20 6-(1-naphthylmethyl) substituted S-DABO derivatives with β-carbonyl group on the C(2) side chain as novel potent non-nucleoside HIV-1 reverse transcriptase inhibitors. The correlation analysis (CA) and stepwise multiple regression analysis (SMR) were performed. The QSAR models indicate that the physicochemical parameters of Qc9, MRR1, ELUMO, ∏R2 and μ have significant influence on the activities of these derivatives. The substitution of hydrophobic R2 and bulky aromatic R1 to form a conjugated system with the frame of those S-DABO series compounds should be considered to design new potent compounds for anti-HIV-1.
基金supported by Natural Science Foundation of Heilongjiang Youth Fund (No. YQ2021B002)Heilongjiang Postdoctoral Scientific Research Developmental Fund (No. LBH-Q20018)State Key Laboratory of Urban Water Resource and Environment (Harbin Institute of Technology)。
文摘A novel air-stable n-type benzothiaphene endcapped azaarene(BTPQ) and its sulfonated derivative(BSPQ) were prepared via two pathways and characterized by NMR, UV–vis, fluorescence and cyclic voltammetry spectroscopy. Symmetrically introducing four nitrogen atoms into acenes, the semiconductor properties could be changed from p-type to n-type detected through the space charge limited current(SCLC) method. After sulfonation of BTPQ, BSPQ is with deeper frontier orbital energy levels and enhanced the electron mobility.
基金the National Natural Science Foundation of China (Grant Nos. 50433020, 50520150165 & 50403022)
文摘A novel organic electron acceptor, N,N′-dipyrimidinyl-3,4,9,10-perylene-tetracarboxylic diimide (DMP), was designed and synthesized. The molecular structure was characterized by FTIR spectrum and elemental analysis. By cyclic voltammetry measurements, DMP was found to possess a lower LUMO energy level than N,N′-diphenyl-3,4,9,10-perylene-tetracarboxylic diimide due to the stronger electron-withdrawing pyrimidinyl group than the phenyl group. Fluorescence quenching is observed in a dual-layer film consisting of a DMP layer and a C60 layer and was attributed to the charge transfer at the interface due to the energy level offset between DMP and C60.
文摘Density functional theory (DFT) calculations were carried out on the compounds Cp2Ln-guan for Ln=Y, Lu, Yb, Dy and Gd, [guan=(iPrN)2CN(iPr)2]. The results were compared with the X-ray structures that were available from the literature; the calculations reproduced quite well the experimental structural features in these complexes exhibiting distorted tetrahedron geometry. The calculated evolution of the Ln-guan bond as a function of the cation showed that lanthanide-ligand distances increased with the increa...
基金Supported by the National Natural Science Foundation of China( No.5 0 172 0 19) and Excellent Young TeachersProgram of MOE,P.R.China.
文摘Two amphiphilic barbituric acid derivatives with a D-π-A structure, 5-(4-dodecyloxybenzylidene)-(1H,3H)-2,4,6-pyrimidinetrione(PB_ 12) and 5-(4-N,N-didodecylaminobenzylidene)-(1H,3H)-2,4,6-pyrimidintrione(AB_ 12) were found to show different aggregation behavior in chloroform. PB_ 12, a derivative with weak electron donating and strong electron drawing substituents, tends to aggregate in a head-to-tail manner, whereas AB_ 12, a derivative with both strong electron donating and drawing substituents, tends to aggregate in a face-to-face manner at a higher concentration. The cyclic voltammograms of AB_ 12 and PB_ 12 show that their energy levels of LUMO approach each other, however, the energy level of HOMO of AB_ 12 is much higher than that of PB_ 12.
文摘The structural properties and vibrational frequencies of 2-phenyl-2-imidazoline have been investigated using theoretical and techniques by which a good correlation was observed. The assignments of the vibrational modes were performed with the help of normal co-ordinate analysis following the Scaled Quantum Mechanical Force Field methodology. Natural bond orbital analysis and the highest occupied molecular orbital-lowest unoccupied molecular orbital gap analysis have been carried out. UV-visible spectrum of the compound was recorded and compared with the theoretical UV-visible spectrum of the title molecule using Symmetry Adapted Cluster-Configuration Interaction method which yielded good agreement. Our results reflect that the title compound can be used as good source of UV light.