A new complex, [Ni（L）2]·2（H2O） I （HL = 2-iminomethyl-6-methoxyphenol）, has been synthesized and structurally determined. The crystal belongs to the trigonal system, space group R3- with a = 1.9341 （3）, b ...A new complex, [Ni（L）2]·2（H2O） I （HL = 2-iminomethyl-6-methoxyphenol）, has been synthesized and structurally determined. The crystal belongs to the trigonal system, space group R3- with a = 1.9341 （3）, b = 1.9341 （3）, C = 1.2048（2） nm, V = 3.9029（11） nm^3, Mr = 395.05, Z = 9, Dc = 1.513 g·cm^-3, F（000） = 1854,μ= 1.153 mm^-1 and S = 1.014. Each Ni^Ⅱ atom is four-coordinated by two N and two O atoms from two different L anions to give a slightly distorted square-plane geometry. The complex forms a 3-D network structure through N-H...O and O-H...O hydrogen bonds containing an interesting six-membered water ring.展开更多
Two representative macrocyclic lactones with methoxysulfonyl side chain（5a and 5b）were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloai...Two representative macrocyclic lactones with methoxysulfonyl side chain（5a and 5b）were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates（1）in total yields of 45 and 57%,respectively.展开更多
Newly designed miktoarm star-shaped copolymers made of poly[(benzyl methacrylate(BMA)-co-(ε-caprolacton)(CL)] and poly[(BMA-b-MMA-b-BMA)-co-ε-caprolacton)(CL)] were synthesized by combining ring-opening polymerizati...Newly designed miktoarm star-shaped copolymers made of poly[(benzyl methacrylate(BMA)-co-(ε-caprolacton)(CL)] and poly[(BMA-b-MMA-b-BMA)-co-ε-caprolacton)(CL)] were synthesized by combining ring-opening polymerization (ROP) of ε-caprolactone (CL) and poly(BMA) five membered lacton fuctionalized prepared via atom transfer radical polymerization (ATRP) of BMA, and ε-CL and P(BMA-b-MMA-b-BMA) dual functionalized diblock copolymer, in the presence of tin(II) bis(2-ethylhexanoate) (Sn(Oct)2). Although lactone ended poly(benzyl methacrylate) with ε-caprolactone monomer gave ring open polymerization by Sn(Oct)2, the macromonomer itself did not give any poly- merization The macromonomers, and the miktoarm star-shaped copolymers were analyzed by FT-IR and 1H-NMR spectroscopies and GPC (gel permeation chromatograph), Differential scanning calorimetry (DSC-50) and termo- gravimetric analysis (TGA-50). These copolymers exhibited the expected structure. The crystallization of star-shaped copolymers was studied by DSC. The results show that when the content of the BMA block increased, the Tm of the star-shaped block copolymer increased.展开更多
Gutman and Wagner(in the matching energy of a graph, Disc. Appl. Math., 2012) defined the matching energy of a graph and pointed out that its chemical applications go back to the 1970 s. Now the research on matching e...Gutman and Wagner(in the matching energy of a graph, Disc. Appl. Math., 2012) defined the matching energy of a graph and pointed out that its chemical applications go back to the 1970 s. Now the research on matching energy mainly focuses on graphs with pendent vertices and only a few papers reported the progress on matching energy of graphs without pendent vertices. For a random six-membered ring spiro chain, the number of k-matchings and the matching energy are random variables. In this paper, we determine the extremal graphs with respect to the matching energy for random six-membered ring spiro chains which have no pendent vertices.展开更多
Two ligands [ortho-C6H4NR2（CH2NH）]2CH2CH2（3： R=Me; 4： R=EO were prepared by the reduction of preligands [ortho-C6H4NR2（CH=N）]zCH2CH2（1： R=Me; 2： R=Et）. These ligands reacted with AIMe3 to afford the corresp...Two ligands [ortho-C6H4NR2（CH2NH）]2CH2CH2（3： R=Me; 4： R=EO were prepared by the reduction of preligands [ortho-C6H4NR2（CH=N）]zCH2CH2（1： R=Me; 2： R=Et）. These ligands reacted with AIMe3 to afford the corresponding dinuclear aluminum complexes {A1Me2[ortho-C6H4NR2（CH2N）]}2CHzCH2（5： R=Me; 6： R=Et）. All the compounds were characterized by 1H and UC nuclear magnetic resonance（NMR） spectroscopies and elemental analyses. The catalytic properties of the aluminum complexes towards the ring-opening polymerization of lactones were investi- gated in the presence of benzvl alcohol. All the oolvmerization reactions were proceeded in a controlled manner.展开更多
Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） wi...Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） with diethyl zinc（ZnEt2） as catalyst. The structures of these polymers were confirmed with hydrogen nuclear magnetic resonance（IH NMR） spectroscopy, carbon nuclear magnetic resonance（13C NMR） spectroscopy and infrared（IR） spectrometer. The thermal decomposition temperature and glass transition temperature of PTSL were 241 and 161 ℃, respectively. A series of mPEG-b-PTSL with different molecular weights（Mn＇s from 7000 to 32000） was obtained by tuning the TSL/mPEG feed ratio. After the removal of the trityl groups, mPEG-block-poly（serine lactone）（mPEG- b-PSL） was obtained as a new kind of cationic block copolymer. Low cytotoxicity of these polymers to L929 cells was confirmed via 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay.展开更多
The localized molecular orbitals and energy levels for four typical conjugated six-membered ring systems C_6H_6, C_3N_3H_3, B_3N_3H_6, and (B_3O_6)^(3-) as well as a non-aromatic reference molecule N_3Cl_6 have been ...The localized molecular orbitals and energy levels for four typical conjugated six-membered ring systems C_6H_6, C_3N_3H_3, B_3N_3H_6, and (B_3O_6)^(3-) as well as a non-aromatic reference molecule N_3Cl_6 have been calculated by using Edmiston-Ruedenberg energy localization technique under the CNDO/2 approximation in order to investigate the nature of aromaticity or quasi-aromaticity of the six-membered ring systems studied. The contour maps for π-type localized MO's (LMO) have been plotted to illustrate the bonding characteristics of the five ring systems studied. These LMO calculations show that for all the conjugated six-membered ring systems considered there exists local delocalization of π-bonds or three-centered and occasionally four-centered two-electron π-bonds in our terminology, and the cooperative effect among these π-bonds leading to the formation of a closed continuous x-conjugation system around the ring, which is necessary for the creation of aromaticity in the systems studied. We have been able to discuss the properties of these three-centered π-bonds in terms of the constituent atoms and electrons and the relevant orbitals involved.展开更多
The localized molecular orbitals (LMOs) of certain quasi-aromatic organic and inor- ganic molecules with six-membered rings have been calculated by virtue of the ab initio method using STO-3G and 4-31G basis sets as w...The localized molecular orbitals (LMOs) of certain quasi-aromatic organic and inor- ganic molecules with six-membered rings have been calculated by virtue of the ab initio method using STO-3G and 4-31G basis sets as well as the CNDO/2 method. It is shown that there exists extensively-delocalized p-pπ bonding in these quasi-aromatic systems. The localized pictures of the π-type LMOs for the heterocyclic and homocyclic systems from the σ-π localization scheme are discussed. The Generator Orbital approach is utilized to account for the bonding patterns.展开更多
Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization...Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1- benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively.展开更多
基金the Key Laboratory of Non-ferrous Metal Materials and New Processing Technology, Ministry of Education and the State Key Laboratory of Coordination Chemistry
文摘A new complex, [Ni（L）2]·2（H2O） I （HL = 2-iminomethyl-6-methoxyphenol）, has been synthesized and structurally determined. The crystal belongs to the trigonal system, space group R3- with a = 1.9341 （3）, b = 1.9341 （3）, C = 1.2048（2） nm, V = 3.9029（11） nm^3, Mr = 395.05, Z = 9, Dc = 1.513 g·cm^-3, F（000） = 1854,μ= 1.153 mm^-1 and S = 1.014. Each Ni^Ⅱ atom is four-coordinated by two N and two O atoms from two different L anions to give a slightly distorted square-plane geometry. The complex forms a 3-D network structure through N-H...O and O-H...O hydrogen bonds containing an interesting six-membered water ring.
文摘Two representative macrocyclic lactones with methoxysulfonyl side chain（5a and 5b）were synthesized employing Michael addition with acrolein and ring enlargement as the key steps,starting from potassium,α-oxocycloaikylsulfonates（1）in total yields of 45 and 57%,respectively.
基金The authors wish to thank the Firat University Research Fund for financial support of this Project(FUBAP-1650)M.Fatih Coskun,who provided chromatograms(GPC)at our university.
文摘Newly designed miktoarm star-shaped copolymers made of poly[(benzyl methacrylate(BMA)-co-(ε-caprolacton)(CL)] and poly[(BMA-b-MMA-b-BMA)-co-ε-caprolacton)(CL)] were synthesized by combining ring-opening polymerization (ROP) of ε-caprolactone (CL) and poly(BMA) five membered lacton fuctionalized prepared via atom transfer radical polymerization (ATRP) of BMA, and ε-CL and P(BMA-b-MMA-b-BMA) dual functionalized diblock copolymer, in the presence of tin(II) bis(2-ethylhexanoate) (Sn(Oct)2). Although lactone ended poly(benzyl methacrylate) with ε-caprolactone monomer gave ring open polymerization by Sn(Oct)2, the macromonomer itself did not give any poly- merization The macromonomers, and the miktoarm star-shaped copolymers were analyzed by FT-IR and 1H-NMR spectroscopies and GPC (gel permeation chromatograph), Differential scanning calorimetry (DSC-50) and termo- gravimetric analysis (TGA-50). These copolymers exhibited the expected structure. The crystallization of star-shaped copolymers was studied by DSC. The results show that when the content of the BMA block increased, the Tm of the star-shaped block copolymer increased.
基金Supported by the the National Natural Science Foundation of China(No.11551003)Scientific research fund of the Science and Technology Program of Guangzhou(No.201510010265)the Qinghai Province Natural Science Foundation(No.2015-ZJ-911)
文摘Gutman and Wagner(in the matching energy of a graph, Disc. Appl. Math., 2012) defined the matching energy of a graph and pointed out that its chemical applications go back to the 1970 s. Now the research on matching energy mainly focuses on graphs with pendent vertices and only a few papers reported the progress on matching energy of graphs without pendent vertices. For a random six-membered ring spiro chain, the number of k-matchings and the matching energy are random variables. In this paper, we determine the extremal graphs with respect to the matching energy for random six-membered ring spiro chains which have no pendent vertices.
基金Supported by the National Natural Science Foundation of China（No.21104026）.
文摘Two ligands [ortho-C6H4NR2（CH2NH）]2CH2CH2（3： R=Me; 4： R=EO were prepared by the reduction of preligands [ortho-C6H4NR2（CH=N）]zCH2CH2（1： R=Me; 2： R=Et）. These ligands reacted with AIMe3 to afford the corresponding dinuclear aluminum complexes {A1Me2[ortho-C6H4NR2（CH2N）]}2CHzCH2（5： R=Me; 6： R=Et）. All the compounds were characterized by 1H and UC nuclear magnetic resonance（NMR） spectroscopies and elemental analyses. The catalytic properties of the aluminum complexes towards the ring-opening polymerization of lactones were investi- gated in the presence of benzvl alcohol. All the oolvmerization reactions were proceeded in a controlled manner.
基金Supported by the National Natural Science Foundation of China（No s.51021003, 21174143）.
文摘Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） with diethyl zinc（ZnEt2） as catalyst. The structures of these polymers were confirmed with hydrogen nuclear magnetic resonance（IH NMR） spectroscopy, carbon nuclear magnetic resonance（13C NMR） spectroscopy and infrared（IR） spectrometer. The thermal decomposition temperature and glass transition temperature of PTSL were 241 and 161 ℃, respectively. A series of mPEG-b-PTSL with different molecular weights（Mn＇s from 7000 to 32000） was obtained by tuning the TSL/mPEG feed ratio. After the removal of the trityl groups, mPEG-block-poly（serine lactone）（mPEG- b-PSL） was obtained as a new kind of cationic block copolymer. Low cytotoxicity of these polymers to L929 cells was confirmed via 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay.
文摘The localized molecular orbitals and energy levels for four typical conjugated six-membered ring systems C_6H_6, C_3N_3H_3, B_3N_3H_6, and (B_3O_6)^(3-) as well as a non-aromatic reference molecule N_3Cl_6 have been calculated by using Edmiston-Ruedenberg energy localization technique under the CNDO/2 approximation in order to investigate the nature of aromaticity or quasi-aromaticity of the six-membered ring systems studied. The contour maps for π-type localized MO's (LMO) have been plotted to illustrate the bonding characteristics of the five ring systems studied. These LMO calculations show that for all the conjugated six-membered ring systems considered there exists local delocalization of π-bonds or three-centered and occasionally four-centered two-electron π-bonds in our terminology, and the cooperative effect among these π-bonds leading to the formation of a closed continuous x-conjugation system around the ring, which is necessary for the creation of aromaticity in the systems studied. We have been able to discuss the properties of these three-centered π-bonds in terms of the constituent atoms and electrons and the relevant orbitals involved.
基金Project supported by the National Natural Science Foundation of China the Foundation of the State Key Laboratory of Structural Chemistry of China
文摘The localized molecular orbitals (LMOs) of certain quasi-aromatic organic and inor- ganic molecules with six-membered rings have been calculated by virtue of the ab initio method using STO-3G and 4-31G basis sets as well as the CNDO/2 method. It is shown that there exists extensively-delocalized p-pπ bonding in these quasi-aromatic systems. The localized pictures of the π-type LMOs for the heterocyclic and homocyclic systems from the σ-π localization scheme are discussed. The Generator Orbital approach is utilized to account for the bonding patterns.
文摘Condensation of methyl 7-methylcoumarin-4-acetate(2)with primary amines and with an- thranilic acid gave 7-methyl-2-oxo-N-aryl-2H-[1]-benzopyran-4--acetamide(4a—d)and(7),respectively. Compound 7 underwent cyclization to give 2-(7-methyl-2-oxo-2H-[1]-benzopyran-4-yl)-methyl-4H-3,1- benzoxazin-4-one(3).The reaction of 3 with aromatic amines gave the corresponding quinazolone derivatives 5 which tautomerises to the thermodynamically more stable isomer 6,whereas its reaction with Grignard reagents and aromatic aldehydes gave 8a,8b,and 9a,9b,respectively.
