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1.
Chih‐Hao Tsao Mitsuru Ueda Ping‐Lin Kuo 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):352-358
A new method to prepare the polymer electrolytes for lithium‐ion batteries is proposed. The polymer electrolytes were prepared by reacting poly(phosphazene)s (MEEPP) having 2‐(2‐methoxyethoxy)ethoxy and 2‐(phenoxy)ethoxy units with 2,4,6‐tris[bis(methoxymethyl)amino]‐1,3,5‐triazine (CYMEL) as a cross‐linking agent. This method is simple and reliable for controlling the cross‐linking extent, thereby providing a straightforward way to produce a flexible polymer electrolyte membrane. The 6 mol % cross‐linked polymer electrolyte (ethylene oxide unit (EO)/Li = 24:1) exhibited a maximum ionic conductivity of 5.36 × 10?5 S cm?1 at 100 °C. The 7Li linewidths of solid‐state static NMR showed that the ionic conductivity was strongly related to polymer segment motion. Moreover, the electrochemical stability of the MEEPP polymer electrolytes increased with an increasing extent of cross‐linking, the highest oxidation voltage of which reached as high as 7.0 V. Moreover, phenoxy‐containing polyphosphazenes are very useful model polymers to study the relationship between the polymer flexibility; that is, the cross‐linking extent and the mobility of metal ions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 352–358 相似文献
2.
Aydan Dag Hakan Durmaz Umit Tunca Gurkan Hizal 《Journal of polymer science. Part A, Polymer chemistry》2009,47(1):178-187
Two types of multiarm star block copolymers: (polystyrene)m‐poly(divinylbenzene)‐poly(methyl methacrylate)n, (PS)m‐polyDVB‐(PMMA)n and (polystyrene)m‐poly(divinylbenzene)‐poly(tert‐butyl acrylate)k, (PS)m‐polyDVB‐(PtBA)k were successfully prepared via a combination of cross‐linking and Diels–Alder click reactions based on “arm‐first” methodology. For this purpose, multiarm star polymer with anthracene functionality as reactive periphery groups was prepared by a cross‐linking reaction of divinyl benzene using α‐anthracene end functionalized polystyrene (PS‐Anth) as a macroinitiator. Thus, obtained multiarm star polymer was then reacted with furan protected maleimide‐end functionalized polymers: PMMA‐MI or PtBA‐MI at reflux temperature of toluene for 48 h resulting in the corresponding multiarm star block copolymers via Diels–Alder click reaction. The multiarm star and multiarm star block copolymers were characterized by using 1H NMR, SEC, Viscotek triple detection SEC (TD‐SEC) and UV. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 178–187, 2009 相似文献
3.
Thiol‐acrylate main‐chain liquid‐crystalline elastomers with tunable thermomechanical properties and actuation strain 下载免费PDF全文
Mohand O. Saed Amir H. Torbati Chelsea A. Starr Rayshan Visvanathan Noel A. Clark Christopher M. Yakacki 《Journal of Polymer Science.Polymer Physics》2017,55(2):157-168
The purpose of this study was to investigate the influence of cross‐linking on the thermomechanical behavior of liquid‐crystalline elastomers (LCEs). Main‐chain LCE networks were synthesized via a thiol‐acrylate Michael addition reaction. The robust nature of this reaction allowed for tailoring of the behavior of the LCEs by varying the concentration and functionality of the cross‐linker. The isotropic rubbery modulus, glass transition temperature, and strain‐to‐failure showed strong dependence on cross‐linker concentration and ranged from 0.9 MPa, 3 °C, and 105% to 3.2 MPa, 25 °C, and 853%, respectively. The isotropic transition temperature (Ti) was shown to be influenced by the functionality of the cross‐linker, ranging from 70 °C to 80 °C for tri‐ and tetra‐functional cross‐linkers. The magnitude of actuation can be tailored by controlling the amount of cross‐linker and applied stress. Actuation increased with increased applied stress and decreased with greater amounts of cross‐linking. The maximum strain actuation achieved was 296% under 100 kPa of bias stress, which resulted in work capacity of 296 kJ/m3 for the lowest cross‐linked networks. Overall, the experimental results provide a fundamental insight linking thermomechanical properties and actuation to a homogenous polydomain nematic LCE networks with order parameters of 0.80 when stretched. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 157–168 相似文献
4.
Preparation of microporous polymers in the form of particles and a thin film from hyperbranched polyphenylenes 下载免费PDF全文
Min Chul Cha Yoonbin Lim Ji Young Chang 《Journal of polymer science. Part A, Polymer chemistry》2015,53(20):2336-2342
The use of a hyperbranched polymer as a building block for the synthesis of a microporous organic polymer was demonstrated. Hyperbranched polyphenylenes (HBPs) were prepared from (3,5‐dibromophenyl)boronic acid, which contained numerous unreacted bromophenyl end groups. Utilizing metal‐catalyzed coupling reactions between these functional groups, cross‐linked porous polymers were obtained. Although the HBPs did not show porosity, their cross‐linked polymers had highly porous structures with Brunauer–Emmett–Teller surface areas of up to 2030 m2/g. An insoluble porous thin film was fabricated by spin casting of a solution containing a HBP followed by Sonogashira cross‐coupling reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2336–2342 相似文献
5.
Albert Y. C. Hung 《Journal of Polymer Science.Polymer Physics》2003,41(7):679-686
The effect of the repeated unit length on the substantially increasing molecular motion and entropy change (?TΔSm) of polymer blends was investigated with solid‐state 13C NMR and differential scanning calorimetry within a miscible window. The hydrogen‐bonding strength, from the formation of the phenolic–polyester interaction, was not high enough to overcome the breaking‐off of the self‐association of the phenolic. With respect to the increasing repeated unit length, the polyester resonance intensity of the solid‐state 13C NMR spectra was weakened because of the reduction in the cross‐polarization efficiency in highly mobile samples. The glass‐transition temperature of the blend and the proton spin–lattice relaxation time from NMR experiments were also reduced. The effect of the reduced hydrogen‐bonding strength on blending brought about a tendency of higher entropy (?TΔSm) and higher molecular mobility of the blend. Accordingly, poly(decamethylene adipate) possessed the longest repeated unit length and exhibited the most mobile one in this phenolic/polyester blend family. The molecular segmental motion and entropy progressively increased while the repeated unit length of the guest polymers increased within a miscible window. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 679–686, 2003 相似文献
6.
Triple responsive block copolymers combining pH‐responsive,thermoresponsive, and glucose‐responsive behaviors 下载免费PDF全文
William L. A. Brooks Gertjan Vancoillie Christopher P. Kabb Richard Hoogenboom Brent S. Sumerlin 《Journal of polymer science. Part A, Polymer chemistry》2017,55(14):2309-2317
Polymers with multiple tunable responses were achieved by incorporating boronic acid functionality along the backbone of a thermoresponsive polymer. The inherent Lewis acidity and diol‐sensitivity of boronic acid moieties allowed these polymers to respond to changes in pH and glucose concentration. Through reversible addition‐fragmentation chain transfer copolymerization of boronic acid‐containing monomers with N‐isopropylacrylamide, well‐defined block copolymers were synthesized containing a hydrophilic N,N‐dimethylacrylamide block and a second, responsive block with temperature‐dependent water solubility, making the resulting polymers capable of self‐assembly into nanostructures upon heating. By incorporating boronic acids within the thermoresponsive block, the cloud point of the polymer depended on the solution conditions, including pH and diol concentration, allowing tunable cloud point ranges. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2309–2317 相似文献
7.
Low thresholds for a nonconventional polymer blend—Amplified spontaneous emission and lasing in F81−x:SYx system 下载免费PDF全文
Haider Butt Kamran ul Hasan Jui‐Fen Chang Ayooye Abigael Olawoyin Richard Henry Friend 《Journal of Polymer Science.Polymer Physics》2016,54(1):15-21
A mixture of two polymer materials, poly (9,9‐dioctylfluorene) (F8), and one of the poly(para‐phenylenevinylene) derivatives, superyellow (SY) have been used to make F81?x:SYx polymer blend system. Under a 3–5 ns pulsed‐laser excitation, this system showed excellent optical properties with low threshold values of ≈14 µJ/cm2 and ≈8 µJ/cm2 for amplified spontaneous emission and optically pumped lasing, respectively. The proposed system was also electroluminescent and an interesting candidate for future research on polymer injection lasers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 15–21 相似文献
8.
Roxan Joncour Dr. Nicolas Susperregui Noël Pinaud Dr. Karinne Miqueu Prof. Eric Fouquet Dr. Jean‐Marc Sotiropoulos Prof. François‐Xavier Felpin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(28):9291-9296
We describe the coupling of anilines with aryl boronic acids, under ligand‐, base‐, and salt‐free conditions at room temperature. This new reaction proceeds through the formation of an aryl palladium alkoxo complex, which allows the transmetalation step with aryl boronic acids without any external base. Importantly, this sustainable procedure generates only environmentally friendly byproducts such as tBuOH, H2O, N2, and B(OH)3. The reaction mechanism has been deeply investigated through experimental and theoretical studies. 相似文献
9.
Heba Gaballa Jiaojiao Shang Sabrina Meier Patrick Theato 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):422-431
Glucose responsive block copolymer featuring boronic acid as a glucose responsive moiety and glycine are reported. The first block is polymerized through reversible addition–fragmentation chain transfer (RAFT) polymerization and the resulting poly(N‐acryloylmorpholine)113 (PAcM) is employed as a macro‐chain transfer agent for chain extension with pentafluorophenyl acrylate (PFPA) yielding a well‐defined PAcM113‐block‐poly(pentafluorophenyl acrylate)84 (PPFPA). The PPFPA block is then reacted with functional (3‐aminomethyl) phenyl boronic acid and glycine via post‐polymerization modification and the structure of the block copolymer is confirmed by proton nuclear magnetic resonance (NMR), 19F NMR, Fourier transform infrared, and gel permeation chromatography. By copolymerizing glycine into the polymer backbone, the relative pKa of the block copolymer is significantly lowered. The block copolymer can self‐assemble into core–shell micelles in aqueous solution and disassemble in response to glucose at the physiological pH. Furthermore, the encapsulation and release of Nile red (NR) as a hydrophobic model drug is studied under the physiological pH. The influence of the glucose concentration on the NR release from the polymeric micelles is demonstrated. These results suggested that the glucose‐responsive poly[(AcM)113‐b‐(3‐(aminomethyl)phenylboronic acid hydrochloride(‐co‐Gly)84] block copolymer has potential applications as a glucose‐responsive polymer for insulin delivery. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 422–431 相似文献
10.
Warapon Sinananwanich Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2008,46(8):2689-2700
A 100% hyperbranched polymer was successfully prepared by using 2‐[4‐(4‐mercaptobutoxy)phenoxy]‐9H‐fluoren‐9‐one as an AB2 monomer in trifluoroacetic acid. The kinetics of the model reaction between 9‐fluorenone and 3‐mercaptopropionic acid was investigated. The reaction obeyed the second‐order kinetics, indicating that the first reaction, that is, the formation of the intermediate from 9‐fluorenone and 3‐mercaptopropionic acid, is considerably slower than the second one, that is, the reaction of the intermediate with 3‐mercaptopropionic acid. On the basis of this finding, a new monomer expected to produce a 100% branched hyperbranched polymer, 2‐[4‐(4‐mercaptobutoxy)phenoxy]‐9H‐fluoren‐9‐one, was designed and prepared. The obtained polymer was characterized by 1H and 13C‐NMR spectroscopy, which confirmed that the polymer was a 100% branched hyperbranched polymer. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2689–2700, 2008 相似文献
11.
Poly(glyceryl glycerol): A multi‐functional hydrophilic polymer for labeling with boronic acids 下载免费PDF全文
Tina Borke Antti Korpi Fabian Pooch Heikki Tenhu Sami Hietala 《Journal of polymer science. Part A, Polymer chemistry》2017,55(11):1822-1830
The synthesis of poly(glyceryl glycerol) (PGG), a polymer featuring a polyethylene oxide backbone and 1,2‐diol groups in every repeating unit, is presented. PGG was prepared by monomer‐activated ring‐opening polymerization of (dl ?1,2‐isopropylidene glyceryl) glycidyl ether, introducing a functional azido‐ or bromo‐head group to each chain. The 1,2‐diol groups, which were released by acidic deprotection, readily reacted with boronic acid derivatives, enabling the attachment of functional moieties under mild aqueous conditions. PGG was conjugated to poly(l ‐lactide) (PLLA) via azide‐alkyne cycloaddition and the resulting copolymer assembled into nanoparticles of 70 nm diameter in aqueous solution. Labeling of the PGG–PLLA particles was achieved by simple mixing with a boronic acid‐functional fluorophore. The labeling efficiency was determined by fluorescence spectroscopy to be 85.5% for boronic acid‐functional rhodamine B compared with 0.2% for plain rhodamine B. The strong interaction of PGG with boronic acids is ascribed to its polyol structure. This study demonstrates the usefulness and versatility of PGG as a hydrophilic polymer for possible biomedical applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 1822–1830 相似文献
12.
Chan Woo Park Hyun Jin Lee Hee‐man Yang Min‐ah Woo Hyun gyu Park Jong‐Duk Kim 《Journal of polymer science. Part A, Polymer chemistry》2011,49(1):203-210
We developed a simple route to prepare stabilized micelles and nanovesicles in aqueous solutions. A hydrophobic poly(succinimide) (PSI) was conjugated with the hydrophilic poly(ethylene glycol) (PEG) as a new type of cross‐linkable unit. Spherical aggregates were formed when dissolving the amphiphilic PEG682‐b‐PSI130 copolymer in aqueous solutions directly, and polymer nanovesicles were prepared by a precipitation‐dialysis method using PEG455‐b‐PSI130 copolymer. Bifunctional primary amine was added to the micelle or nanovesicle solutions to prepare cross‐linked structures via aminolysis reaction of the succinimide units. The degree of cross‐linking was controlled by adjusting the molar ratio of the cross‐linker to the succinimide units. Increasing the degree of cross‐linking leads to the compaction of the micelle core thus reduced diameter. The cross‐linked polymer micelles or nanovesicles maintained their morphology in extremely diluted solutions because of their structural stability. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
13.
Solid state 1H NMR line‐shape analysis and (double quantum) DQ 1H NMR experiments have been used to investigate the segmental and polymer chain dynamics as a function of temperature for a series of thermosetting epoxy resins produced using different diamine curing agents. In these thermosets, chemical crosslinks introduce topological constraints leading to residual stresses during curing. Materials containing a unique ferrocene‐based diamine (FcDA) curing agent were evaluated to address the role of the ferrocene fluxional process on the atomic‐level polymer dynamics. At temperatures above the glass transition temperature (Tg), the DQ 1H NMR experiments provided a measure of the relative effective crosslink and entanglement densities for these materials and revealed significant polymer chain dynamic heterogeneity in the FcDA‐cured thermosets. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1143–1156 相似文献
14.
Decarboxylative Conjunctive Cross‐coupling of Vinyl Boronic Esters using Metallaphotoredox Catalysis
Riccardo S. Mega Vincent K. Duong Adam Noble Varinder K. Aggarwal 《Angewandte Chemie (International ed. in English)》2020,59(11):4375-4379
The synthesis of complex alkyl boronic esters through conjunctive cross‐coupling of vinyl boronic esters with carboxylic acids and aryl iodides is described. The reaction proceeds under mild metallaphotoredox conditions and involves an unprecedented decarboxylative radical addition/cross‐coupling cascade of vinyl boronic esters. Excellent functional‐group tolerance is displayed, and application of a range of carboxylic acids, including secondary α‐amino acids, and aryl iodides provides efficient access to highly functionalized alkyl boronic esters. The decarboxylative conjunctive cross‐coupling was also applied to the synthesis of sedum alkaloids. 相似文献
15.
《Magnetic resonance in chemistry : MRC》2003,41(4):269-272
A series of areneboronic acids were studied by NMR spectroscopy. Increments for the 1H and 13C chemical shifts caused by the boronic acid substituent B(OH)2 in areneboronic acids were determined. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
16.
Masataka Nojima Takeru Kamigawara Yoshihiro Ohta Tsutomu Yokozawa 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):297-304
We report Suzuki–Miyaura coupling polymerization of tetraalkoxy‐substituted 4‐bromostilbene‐4′‐boronic acid 1 with several t‐Bu3P‐ligated Pd initiators; this is the first example of catalyst‐transfer condensation polymerization (CTCP) of a monomer containing a carbon–carbon double bond. When o‐tolylPd(tBu3P)Br was used as the initiator, the o‐tolyl group was not introduced at the polymer end, but polymer with boronic acid at one end and bromine at the other was obtained. However, when we employed stilbenePd(tBu3P)I generated in situ from iodostilbene and Pd(tBu3P)G2 precatalyst, or isolated ArPd(tBu3P)X (Ar, X = Ph, I; o‐tolyl, I; and Ph, Br), the aryl group was introduced at the polymer end, indicating that CTCP of 1 proceeded. Therefore, the iodide and aryl group of the Pd initiator complex is crucial for CTCP of 1 . However, the molecular weight distribution of the obtained polymer was broad, possibly because coordination of the carbon–carbon double bond of 1 to ArPd(tBu3P)I resulted in slow initiation. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 297–304 相似文献
17.
Efficient fabrication of polymer nanoparticles via sonogashira cross‐linking of linear polymers in dilute solution 下载免费PDF全文
Alka Prasher Conor M. Loynd Bryan T. Tuten Peter G. Frank Danming Chao Erik B. Berda 《Journal of polymer science. Part A, Polymer chemistry》2016,54(1):209-217
The synthesis of single‐chain nanoparticles by palladium‐catalyzed Sonogashira coupling between a terminal alkyne and a di‐halo aryl cross‐linker is reported. Statistical copolymers with trimethylsilyl protected alkyne groups pendent to the linear methacrylate back bones were synthesized using reversible addition‐fragmentation chain transfer polymerization post polymerization de‐protection providing terminal alkyne functionalized linear polymer chains. These linear polymer chains were intramolecularly cross‐linked via bifunctional cross‐linkers. The resulting well‐defined covalently bonded nanoparticles were characterized via triple‐detection size exclusion chromatography where MALS detector provided molecular weight information and viscometric detection characterizes particle size and conformations. The particle size could be readily tuned through polymer molecular weight and by degree of cross‐linking. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 209–217 相似文献
18.
Richard Hoogenboom Hanneke M. L. Thijs Martin W. M. Fijten Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2007,45(23):5371-5379
The synthesis of statistical copolymers consisting of 2‐ethyl‐2‐oxazoline (EtOx) and 2‐“soy alkyl”‐2‐oxazoline (SoyOx) via a microwave‐assisted cationic ring‐opening polymerization procedure is described. The majority of the resulting copolymers revealed polydispersity indices below 1.30. The reactivity ratios (rEtOx 1.4 ± 0.3; rSoyOx = 1.7 ± 0.3) revealed a clustered monomer distribution throughout the polymer chains. The thermal and surface properties of the pEtOx‐stat‐SoyOx copolymers were analyzed before and after UV‐curing demonstrating the decreased chain mobility after cross‐linking. In addition, the cross‐linked materials showed shape‐persistent swelling upon absorption of water from the air, whereby as little as 5 mol % SoyOx was found to provide efficient cross‐linking. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5371,–5379, 2007 相似文献
19.
Synthesis and characterization of a new phenanthrenequinoxaline‐based polymer for organic solar cells 下载免费PDF全文
Eunsol Jo Jong Baek Park Woo‐Hyung Lee Ji‐Hoon Kim In Hwan Jung Do‐Hoon Hwang In‐Nam Kang 《Journal of polymer science. Part A, Polymer chemistry》2016,54(17):2804-2810
Two donor–acceptor (D‐A) conjugated polymers, PQx and PphQx, composed of alkylthienyl‐substituted benzo[1,2‐b:4,5‐b']dithiophene (BDTT) as the electron donor and the new electron acceptors quinoxaline (Qx) or phenanthrenequinoxaline (phQx), were synthesized with Stille cross‐coupling reactions. The number‐averaged molecular weights (Mn) of PQx and PphQx were found to be 25.1 and 23.2 kDa, respectively, with a dispersity of 2.6. The band‐gap energies of PQx and PphQx are 1.82 and 1.75 eV, respectively. These results indicate that, because phQx units have highly planar structures, their inclusion in D‐A polymers will be a very effective method for increasing the polymers' effective conjugation lengths. The hole mobilities of PQx and PphQx were determined to be 5.0 × 10?5 and 2.2 × 10?4 cm2 V?1 s?1, respectively. A polymer solar cell device prepared with PphQx as the active layer was found to exhibit a power conversion efficiency (PCE) of 5.03%; thus, the introduction of phQx units enhanced both the short circuit current density and PCE of the device. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2804–2810 相似文献
20.
Alexandra I. Costa Luís F. V. Ferreira José V. Prata 《Journal of polymer science. Part A, Polymer chemistry》2008,46(19):6477-6488
A novel fluorescent (p‐phenylene ethynylene)‐calix[4]arene‐based polymer ( CALIX‐PPE ) has been successfully synthesized by cross‐coupling polymerization of bis‐calix[4]arene 1 with 1,4‐diethynylbenzene. The polycondensation was carried out in toluene/NEt3 at 35 °C for 24 h, using PdCl2(PPh3)2/CuI as the catalytic system, furnishing CALIX‐PPE in excellent isolated yields (higher than 95%, several runs). The yellow polymer is freely soluble in several nonprotic organic solvents. The GPC trace of the isolated polymer showed a monomodal distribution and a number‐average molecular weight of 23,300 g mol?1 (Mw/Mn = 2.05). No evidence was found in the structural analysis (FTIR and 1H/13C NMR) regarding the formation of alkyne homocoupled segments along the polymer chain. For comparative purposes, the synthesis of an analogous poly(p‐phenylene ethynylene) containing p‐t‐butyl‐phenoxymethyl side chains ( TBP‐PPE ) was also undertaken. A great similarity was found between the photophysical properties of CALIX‐PPE and TBP‐PPE in solution (UV–vis and laser induced luminescence), clearly demonstrating their unique dependence on the structure and conformation of the conjugated PPE backbone. The fluorescence spectra of polymers are of nearly identical shape, displaying their maximum emission around 420 nm. The calculated solution photoluminescence quantum yields of CALIX‐PPE and TBP‐PPE are of similar magnitude (?F( CALIX‐PPE ) = 0.43; ?F( TBP‐PPE ) = 0.51). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6477–6488, 2008 相似文献