Semi-empirical method PM3 was used to study the geometry and vibrational spectrum of N-(2-hydroxy-l-naphthyl-methylene)-l-pyrenamine (NPY) with the intermediate hydrogen bond. Results are comparable to experimentation...Semi-empirical method PM3 was used to study the geometry and vibrational spectrum of N-(2-hydroxy-l-naphthyl-methylene)-l-pyrenamine (NPY) with the intermediate hydrogen bond. Results are comparable to experimentations. Based on results of both NPY and its model, N-(2-hydroxy-l-naphthyl-methylene)aniline, it was found that the N-(2-hydroxy-l-naphthyl-methylene) group is principally responsible for the special hydrogen bonding through conjugation effect.展开更多
The reaction of bis-[2-amino-4-pheny1-5-thiazolyl] disulfide with 5-nitro-salicylaldehyde in absolute ethanol resulted in the formation of a new Schiff base ligand H<sub>2</sub>L (1). Characterization of t...The reaction of bis-[2-amino-4-pheny1-5-thiazolyl] disulfide with 5-nitro-salicylaldehyde in absolute ethanol resulted in the formation of a new Schiff base ligand H<sub>2</sub>L (1). Characterization of the ligand was performed by FT-IR, <sup>1</sup>H NMR, <sup>13</sup>C NMR, UV-Vis, elemental analysis and single crystal X-ray diffraction. The ligand, (1), possesses a disulfide –S–S– bridge of 2.1121 (3) ? length, and the molecule adopts a cis-conformation around this bond. In the crystal structure of (1), an intramolecular O–H···N hydrogen bond with D… A distance of 2.69 (3) ? was present. The reaction of (1) with Co(NO<sub>3</sub>)<sub>2</sub>·6H<sub>2</sub>O and CuCl<sub>2</sub>·2H<sub>2</sub>O in methanol afforded the corresponding metal complexes. The obtained solids were further investigated by elemental analysis and UV-Vis titration that confirmed the formation of [CoL] and [ClCuHL] complexes. However, recrystallizaion of the Co(II) complex in dimethylsulfoxide caused the complete hydrolysis of the imine bond and afforded a Co(II) complex in which two 5-nitro-salicylaldehyde and two DMSO molecules were coordinated to the central metal in an octahedral fashion. This structure (2) was also confirmed by single crystal X-ray analysis.展开更多
A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu（naphdien）]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethylenetriamine, has been synthesized and d...A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu（naphdien）]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethylenetriamine, has been synthesized and determined by single-crystal X-ray diffraction. It belongs to the monoclinic system, space group P21/c, with a = 7.3490（15）, b = 7.0847（16）, c = 30.845（3）A, β= 95.33（3）°, V = 1599.0（5）A3, Z = 4, C15 H20ClCuN3O2, Mr = 373.33, De = 1.551 g/cm3, μ = 1.543 mm^-1, F（000） = 772, R = 0.0536 and wR = 0.0927 for 2788 unique reflections with 1659 observed ones （I 〉2σ（I））. In the crystal structure, mononuclear units [Cu（naphdien）]Cl·H2O are linked into a two-dimensional framework via strong hydrogen bonds, and extended into a three-dimensional supramolecular structure through π-π stacking interactions.展开更多
A novel two-dimensional self-assembly network formulated as [K（TSSB）]n （TSSB= taurine-salicylaldehyde Schiff base） has been synthesized via the reaction of salicylaldehyde with taurine at the presence of potassium...A novel two-dimensional self-assembly network formulated as [K（TSSB）]n （TSSB= taurine-salicylaldehyde Schiff base） has been synthesized via the reaction of salicylaldehyde with taurine at the presence of potassium hydroxide in water-methanol solution,and was structurally characterized by elemental analysis,IR,UV-VIS spectra and X-ray diffraction.It crystallizes in the monoclinic system,space group P21/c with a=20.245（3）,b=7.2905（9）,c=7.5458（10）,β= 94.1920（10）o,V=1110.8（2）3,Mr=267.34,Z=4,Dc=1.599 g/cm3,μ（MoKα）=0.663 mm-1 and F（000）=552.The units of K[TSSB] are linked into a one-dimensional double chain structure via the sulfonic groups from the taurine-salicylaldelyde Schiff base,and such chains are further extended through O-K-O bond interactions resulting in a two-dimensional supramolecular architecture.In the complex,the K（I） ion displays a slightly distorted dodecahedral geometry with an eight-coordination number.展开更多
A novel binuclear complex （[Cu^2（μ2-shed）（hshed）].（CIO4）,H2O, h2shed = N-salicylidene-N＇-（2-hydroxyethyl）ethylenediamine） has been synthesized and structurally characterized by X-ray diffraction analysis. ...A novel binuclear complex （[Cu^2（μ2-shed）（hshed）].（CIO4）,H2O, h2shed = N-salicylidene-N＇-（2-hydroxyethyl）ethylenediamine） has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 12.511（10）, b = 15.750（12）, c = 14.281 （12） A, β = 100.564（14）°, C22H31CIN4O9Cu2, Mr = 658.04, V = 2766（4） A^3, Z = 4, Dc = 1.580 g/cm^3,μ（MoKα = 1.689 mm^-1, F（000） = 1352, the final R = 0.0528 and wR = 0.1433 for 4880 independent reflections with Rint = 0.0577. The complex is a binuclear copper compound, and two Cu（Ⅱ） ions in the binuclear cation are in different coordination environments. The Cu（1） ion adopts a distorted square pyramidal geometry （x = 0.22） with four donor atoms （N2O2） of the ligand in the basal plane, and one hydroxyl oxygen atom with protonated form occupying the apical position. The Cu（2） ion assumes the geometry of a distorted square plane with four donor atoms （N2O2） of the ligand. The Cu...Cu separation is 3.103 A,. In addition, N-H…O and C-H…O intermolecular hydrogen bonding interactions link these binuclear cations into a quasi one-dimensional chain along the a axis.展开更多
Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and ma...Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and magnetic properties were determined and investigated. The H-bonding interactions concern just in neighbor cation and anion, do not extend into network for both 1 and 2. The temperature dependence of the magnetic susceptibilities (2-300K) showed that 1 is diamagnetism and 2 is paramagnetism with weak antiferromagnetic exchange interactions between adjacent spin carriers, no magnetic ordering taking place in these two complexes.展开更多
A novel pyridine-contained a-cyanostilbenzene Schiff base, （Z）-3-（4-butoxy- phenyl）-2-（4-（（E）-pyridin-2-yl-methyleneamino）phenyl）acrylonitrile （L）, has been synthesized and characterized by 1H NMR, 13C NMR...A novel pyridine-contained a-cyanostilbenzene Schiff base, （Z）-3-（4-butoxy- phenyl）-2-（4-（（E）-pyridin-2-yl-methyleneamino）phenyl）acrylonitrile （L）, has been synthesized and characterized by 1H NMR, 13C NMR, FT-IR spectra and single-crystal X-ray diffraction. Single-crystal data show that compound L belongs to the triclinic system, space group P1, with a = 8.759（4）, b = 10.779（4）, c = 12.594（5） A, a= 65.873（4）, β = 88.332（5）, 7= 73.800（5）°, M,. = 381.46, V= 1037.2（7） A3, Z = 2, Dc = 1.221 g/cm-3,μ = 0.076 mm-1, F（000） = 404, gint = 0.0311, R （I〉 20（I）） = 0.0484, wR （I 〉 20（I）） = 0.1544, R （all data） = 0.0484, wR （all data） = 0.1692, completeness to theta = 25.000 being 99.0% and GOF = 1.179. There are two kinds of intermolecular hydrogen bonds and one kind of C-H……π weak interaction between adjacent molecules. Compound L can be used as a candidate for desirable devices with high performance due to its good thermal stability and excellent optical performance.展开更多
The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA wi...The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2]（ClO4）E·H2O 1 and [CoL2]（NO3）E·H2O 2 as isolatable products （L= N-（1- benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine）, where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1： monoclinic, space group P21/c, a = 11.9214（10）, b = 23.5828（17）, c = 14.0387（12）A, β = 135.219（4）°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1（4） A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ（MoKa） = 0.876 mm^-1, F（000） = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections （I 〉 2σ（I））. Crystal data for complex 2： monoclinic, space group P21/c, a = 18.2162（16）, b = 10.0610（6）, c = 18.593（2）A, β = 130.099（3）°, C22H30CoN10O7, Mr = 605.49, V = 2606.5（4） A3 Z = 4, Dc = 1.543 g/cm^3,μ（MoKa） = 0.722 mm^-1, F（000） = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- （or NO3^-） groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.展开更多
The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = ...The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = 0.93 cm-1 and F(000) = 504.00. The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I > 2s(I)), respectively. The dihedral angle between the two phenyl rings is 52.9 and that between the NO2 group and its attached ring is 3.0. In the crystal, molecules are stacked along [100] through p…p interactions. The CH…O hydrogen bond (3.403 ? 120.4? laterally connects the stacks along [010] to form networks (001) which are further anti- parallelly connected by CH…O (3.382 ? 142.9) and p…p interactions extending along [001]. Also presented here is a brief study on the CH…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types, namely, )5(12R, )4(21R, )8(22R, )6(12R and )7(22R, with the first three occurring more often.展开更多
In the crystal structures of N-salicylidene-anilines, the ortho-OH group with the central N atom forms a planar six-membered ring through intramolecular hydrogen bonds (Fig. 1). The pseudo-aromatic ring is coplanar wi...In the crystal structures of N-salicylidene-anilines, the ortho-OH group with the central N atom forms a planar six-membered ring through intramolecular hydrogen bonds (Fig. 1). The pseudo-aromatic ring is coplanar with its attached phenyl ring. The resonance strengthens the H-bond through proton transfer between the O and N atoms (Fig. 1, I II): dCO and dCC become shorter and dCN longer significantly. The d1～d6 are also changed regularly. According to the geometries obtained from X-ray analysis and retrieved from the Cambridge Structural Database (CSD, version 5.21)[1], we believe that the main resonance, at least in solid state, is the molecular keto form (II, Fig. 1) instead of the zwitterionic one (III, Fig. 1).展开更多
以均苯三甲酰肼(1,3,5-Benzenetricarbohydrazide,BTH)和对苯二甲醛(1,4-phthalaldehyde,PD)为有机单体构建模块,根据席夫碱(Schiff-base)反应原理和网状化学的设计思想,设计合成了一种新的腙键共价有机聚合物(BTH-PD-COP)。采用傅里叶...以均苯三甲酰肼(1,3,5-Benzenetricarbohydrazide,BTH)和对苯二甲醛(1,4-phthalaldehyde,PD)为有机单体构建模块,根据席夫碱(Schiff-base)反应原理和网状化学的设计思想,设计合成了一种新的腙键共价有机聚合物(BTH-PD-COP)。采用傅里叶变换红外光谱(FT-IR)、固体核磁(13 C NMR)、扫描电子显微镜(SEM)、X射线粉末衍射(XRD)、热重分析(TGA)等分别对BTH-PD-COP材料进行了结构和性能表征。结果表明,BTH-PD-COP材料具有优异的物理化学性能。展开更多
文摘Semi-empirical method PM3 was used to study the geometry and vibrational spectrum of N-(2-hydroxy-l-naphthyl-methylene)-l-pyrenamine (NPY) with the intermediate hydrogen bond. Results are comparable to experimentations. Based on results of both NPY and its model, N-(2-hydroxy-l-naphthyl-methylene)aniline, it was found that the N-(2-hydroxy-l-naphthyl-methylene) group is principally responsible for the special hydrogen bonding through conjugation effect.
文摘The reaction of bis-[2-amino-4-pheny1-5-thiazolyl] disulfide with 5-nitro-salicylaldehyde in absolute ethanol resulted in the formation of a new Schiff base ligand H<sub>2</sub>L (1). Characterization of the ligand was performed by FT-IR, <sup>1</sup>H NMR, <sup>13</sup>C NMR, UV-Vis, elemental analysis and single crystal X-ray diffraction. The ligand, (1), possesses a disulfide –S–S– bridge of 2.1121 (3) ? length, and the molecule adopts a cis-conformation around this bond. In the crystal structure of (1), an intramolecular O–H···N hydrogen bond with D… A distance of 2.69 (3) ? was present. The reaction of (1) with Co(NO<sub>3</sub>)<sub>2</sub>·6H<sub>2</sub>O and CuCl<sub>2</sub>·2H<sub>2</sub>O in methanol afforded the corresponding metal complexes. The obtained solids were further investigated by elemental analysis and UV-Vis titration that confirmed the formation of [CoL] and [ClCuHL] complexes. However, recrystallizaion of the Co(II) complex in dimethylsulfoxide caused the complete hydrolysis of the imine bond and afforded a Co(II) complex in which two 5-nitro-salicylaldehyde and two DMSO molecules were coordinated to the central metal in an octahedral fashion. This structure (2) was also confirmed by single crystal X-ray analysis.
基金This work was supported by the National Natural Science Foundation of China (Nos. 20671011, 20331010, 90406002 and 90406024)the 111 Project (B07012) and Key Laboratory of Structural Chemistry Foundation (No. 060017)
文摘A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu（naphdien）]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethylenetriamine, has been synthesized and determined by single-crystal X-ray diffraction. It belongs to the monoclinic system, space group P21/c, with a = 7.3490（15）, b = 7.0847（16）, c = 30.845（3）A, β= 95.33（3）°, V = 1599.0（5）A3, Z = 4, C15 H20ClCuN3O2, Mr = 373.33, De = 1.551 g/cm3, μ = 1.543 mm^-1, F（000） = 772, R = 0.0536 and wR = 0.0927 for 2788 unique reflections with 1659 observed ones （I 〉2σ（I））. In the crystal structure, mononuclear units [Cu（naphdien）]Cl·H2O are linked into a two-dimensional framework via strong hydrogen bonds, and extended into a three-dimensional supramolecular structure through π-π stacking interactions.
基金supported by the National Natural Science Foundation of China (Nos. 20771054 and 20971104)the Natural Science Foundation of Henan Province (No. 0311021200)
文摘A novel two-dimensional self-assembly network formulated as [K（TSSB）]n （TSSB= taurine-salicylaldehyde Schiff base） has been synthesized via the reaction of salicylaldehyde with taurine at the presence of potassium hydroxide in water-methanol solution,and was structurally characterized by elemental analysis,IR,UV-VIS spectra and X-ray diffraction.It crystallizes in the monoclinic system,space group P21/c with a=20.245（3）,b=7.2905（9）,c=7.5458（10）,β= 94.1920（10）o,V=1110.8（2）3,Mr=267.34,Z=4,Dc=1.599 g/cm3,μ（MoKα）=0.663 mm-1 and F（000）=552.The units of K[TSSB] are linked into a one-dimensional double chain structure via the sulfonic groups from the taurine-salicylaldelyde Schiff base,and such chains are further extended through O-K-O bond interactions resulting in a two-dimensional supramolecular architecture.In the complex,the K（I） ion displays a slightly distorted dodecahedral geometry with an eight-coordination number.
文摘A novel binuclear complex （[Cu^2（μ2-shed）（hshed）].（CIO4）,H2O, h2shed = N-salicylidene-N＇-（2-hydroxyethyl）ethylenediamine） has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 12.511（10）, b = 15.750（12）, c = 14.281 （12） A, β = 100.564（14）°, C22H31CIN4O9Cu2, Mr = 658.04, V = 2766（4） A^3, Z = 4, Dc = 1.580 g/cm^3,μ（MoKα = 1.689 mm^-1, F（000） = 1352, the final R = 0.0528 and wR = 0.1433 for 4880 independent reflections with Rint = 0.0577. The complex is a binuclear copper compound, and two Cu（Ⅱ） ions in the binuclear cation are in different coordination environments. The Cu（1） ion adopts a distorted square pyramidal geometry （x = 0.22） with four donor atoms （N2O2） of the ligand in the basal plane, and one hydroxyl oxygen atom with protonated form occupying the apical position. The Cu（2） ion assumes the geometry of a distorted square plane with four donor atoms （N2O2） of the ligand. The Cu...Cu separation is 3.103 A,. In addition, N-H…O and C-H…O intermolecular hydrogen bonding interactions link these binuclear cations into a quasi one-dimensional chain along the a axis.
文摘Two new Schiff base complexes, [NiL]ClO4 1 and [CuL]ClO40.5H2O 2, were synthesized and characterized, where L is the 1:1 condensation product of salicylaldehyde and diethylenetriamine. Their crystal structures and magnetic properties were determined and investigated. The H-bonding interactions concern just in neighbor cation and anion, do not extend into network for both 1 and 2. The temperature dependence of the magnetic susceptibilities (2-300K) showed that 1 is diamagnetism and 2 is paramagnetism with weak antiferromagnetic exchange interactions between adjacent spin carriers, no magnetic ordering taking place in these two complexes.
基金supported by the National Natural Science Foundation of China(21101001)the Educational Commission of Anhui Province(KJ2014ZD02)
文摘A novel pyridine-contained a-cyanostilbenzene Schiff base, （Z）-3-（4-butoxy- phenyl）-2-（4-（（E）-pyridin-2-yl-methyleneamino）phenyl）acrylonitrile （L）, has been synthesized and characterized by 1H NMR, 13C NMR, FT-IR spectra and single-crystal X-ray diffraction. Single-crystal data show that compound L belongs to the triclinic system, space group P1, with a = 8.759（4）, b = 10.779（4）, c = 12.594（5） A, a= 65.873（4）, β = 88.332（5）, 7= 73.800（5）°, M,. = 381.46, V= 1037.2（7） A3, Z = 2, Dc = 1.221 g/cm-3,μ = 0.076 mm-1, F（000） = 404, gint = 0.0311, R （I〉 20（I）） = 0.0484, wR （I 〉 20（I）） = 0.1544, R （all data） = 0.0484, wR （all data） = 0.1692, completeness to theta = 25.000 being 99.0% and GOF = 1.179. There are two kinds of intermolecular hydrogen bonds and one kind of C-H……π weak interaction between adjacent molecules. Compound L can be used as a candidate for desirable devices with high performance due to its good thermal stability and excellent optical performance.
基金the National Natural Science Foundation of China (20425313)the Natural Science Foundation of Fujian Province (2005HZ01-1, 2006L2005, 2006F3135, 2006J0183)
文摘The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2]（ClO4）E·H2O 1 and [CoL2]（NO3）E·H2O 2 as isolatable products （L= N-（1- benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine）, where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1： monoclinic, space group P21/c, a = 11.9214（10）, b = 23.5828（17）, c = 14.0387（12）A, β = 135.219（4）°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1（4） A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ（MoKa） = 0.876 mm^-1, F（000） = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections （I 〉 2σ（I））. Crystal data for complex 2： monoclinic, space group P21/c, a = 18.2162（16）, b = 10.0610（6）, c = 18.593（2）A, β = 130.099（3）°, C22H30CoN10O7, Mr = 605.49, V = 2606.5（4） A3 Z = 4, Dc = 1.543 g/cm^3,μ（MoKa） = 0.722 mm^-1, F（000） = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- （or NO3^-） groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.
文摘The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = 0.93 cm-1 and F(000) = 504.00. The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I > 2s(I)), respectively. The dihedral angle between the two phenyl rings is 52.9 and that between the NO2 group and its attached ring is 3.0. In the crystal, molecules are stacked along [100] through p…p interactions. The CH…O hydrogen bond (3.403 ? 120.4? laterally connects the stacks along [010] to form networks (001) which are further anti- parallelly connected by CH…O (3.382 ? 142.9) and p…p interactions extending along [001]. Also presented here is a brief study on the CH…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types, namely, )5(12R, )4(21R, )8(22R, )6(12R and )7(22R, with the first three occurring more often.
基金This research was supported by the Key Subject Foundation of Jiangsu Province
文摘In the crystal structures of N-salicylidene-anilines, the ortho-OH group with the central N atom forms a planar six-membered ring through intramolecular hydrogen bonds (Fig. 1). The pseudo-aromatic ring is coplanar with its attached phenyl ring. The resonance strengthens the H-bond through proton transfer between the O and N atoms (Fig. 1, I II): dCO and dCC become shorter and dCN longer significantly. The d1～d6 are also changed regularly. According to the geometries obtained from X-ray analysis and retrieved from the Cambridge Structural Database (CSD, version 5.21)[1], we believe that the main resonance, at least in solid state, is the molecular keto form (II, Fig. 1) instead of the zwitterionic one (III, Fig. 1).
文摘以均苯三甲酰肼(1,3,5-Benzenetricarbohydrazide,BTH)和对苯二甲醛(1,4-phthalaldehyde,PD)为有机单体构建模块,根据席夫碱(Schiff-base)反应原理和网状化学的设计思想,设计合成了一种新的腙键共价有机聚合物(BTH-PD-COP)。采用傅里叶变换红外光谱(FT-IR)、固体核磁(13 C NMR)、扫描电子显微镜(SEM)、X射线粉末衍射(XRD)、热重分析(TGA)等分别对BTH-PD-COP材料进行了结构和性能表征。结果表明,BTH-PD-COP材料具有优异的物理化学性能。
