- Development of n-type semiconductor based on cyclopentene- or cyclohexene-fused [C60]-fullerene derivatives
-
Properties of cyclopentene- or cyclohexene-fused [C60]-fullerene derivatives as the acceptor in photovoltaic cells have been investigated by use of poly(3-hexylthiophene) (P3HT) as the model donor polymer. Several cyclopentene- or cyclohexene-fused [C60]-fullerene derivatives show high power conversion efficiency (PCE). The highest PCE was obtained for 3′,6′-dihydro-4′-phenoxycarbonyl-6′-methylbenzo[1,9][5,6](C60-Ih)fullerene (3.2%); this is superior to that of [C60]-PCBM with the P3HT polymer under the same experimental conditions. PCE of the OPV devices with alkyl-substituted cyclohexene-fused [C60]-fullerenes depended on the alkyl substituent on the cyclohexene ring; compounds with substituents of odd-number alkyl groups showed better PCE than those compounds possessing even-number alkyl groups.
- Yamane, Yu,Sugawara, Kiyotaka,Nakamura, Naoshi,Hayase, Shuichi,Nokami, Toshiki,Itoh, Toshiyuki
-
-
Read Online
- Synthesis and evaluation of a novel hydrophobically associating polymer based on acrylamide for enhanced oil recovery
-
A novel polymerizable hydrophobic monomer 1-(4-dodecyloxy-phenyl)-propenone (DPP) was synthesized by esterification, Frise rearrangement and Williamson etherification; then, the obtained DPP was copolymerized with 2-(acrylamido)-dodecanesulfonic acid (AMC12S) and acrylamide (AM) initiated by a redox initiation system in an aqueous medium to enhance oil recovery (EOR). AM/AMC12S/DPP (PADP) was characterized by FT-IR, 1H NMR spectroscopy, environmental scanning electron microscopy (ESEM), DSC-TG, fluorescent probe, core flood test, etc. Results of ESEM and fluorescent probe indicate that hydrophobic microdomains and associating threedimensional networks were formed in the aqueous solution of PADP. Results of DSC-TG demonstrated that long carbon chains, aromatic groups and sulfonic groups were incorporated into the PADP polymer, which can lead to a significant increase of the rigidity of molecular chains. Performance evaluation of experiments showed superior properties in regard to temperature-tolerance, shear-tolerance and salt-tolerance. In the Sandpack Flooding Test, PADP brine solution showed a significant increase in EOR at 65°C because of its high thickening capability. All these features indicate that PADP has a potential application in EOR at harsh conditions.
- Sun, Jin-Sheng,Du, Wei-Chao,Pu, Xiao-Lin,Zou, Zhuan-Zheng,Zhu, Bo-Bo
-
-
Read Online
- Acid- And base-switched palladium-catalyzed γ-C(sp3)-H alkylation and alkenylation of neopentylamine
-
The functionalization of remote unactivated C(sp3)-H and the reaction selectivity are among the core pursuits for transition-metal catalytic system development. Herein, we report Pd-catalyzed γ-C(sp3)-H-selective alkylation and alkenylation with removable 7-azaindole as a directing group. Acid and base were found to be the decisive regulators for the selective alkylation and alkenylation, respectively, on the same single substrate under otherwise the same reaction conditions. Various acrylates were compatible for the formation of C(sp3)-C(sp3) and C(sp3)-C(sp2) bonds. The alkenylation protocol could be further extended to acrylates with natural product units and α,β-unsaturated ketones. The preliminary synthetic manipulation of the alkylation and alkenylation products demonstrates the potential of this strategy for structurally diverse aliphatic chain extension and functionalization. Mechanistic experimental studies showed that the acidic and basic catalytic transformations shared the same six-membered dimer palladacycle.
- Zhang, Jinquan,Zhang, Shuaizhong,Zou, Hongbin
-
supporting information
p. 3466 - 3471
(2021/05/31)
-
- Palladium-catalyzed regioselective synthesis of B(4,5)-or B(4)-substituted: O-carboranes containing α,β-unsaturated carbonyls
-
With the help of a carboxylic acid directing group, Pd-catalyzed regioselective synthesis of B(4,5)-or B(4)-substituted o-carboranes containing α,β-unsaturated carbonyls has been reported. The-COOH, removed during the course of the reaction, is responsible for controlling the regioselectivity. The desired products could be obtained in moderate to good yields.
- Li, Jiaoyi,Lu, Jian,Tian, Song,Wang, Qian,Zhang, Chuyi,Zhang, Jianwei,Zhou, Ling
-
p. 4723 - 4727
(2020/07/13)
-
- Palladium-catalyzed remote C-H functionalization of 2-aminopyrimidines
-
A straightforward strategy was developed for the arylation and olefination at the C5-position of the N-(alkyl)pyrimidin-2-amine core with readily available aryl halides and alkenes, respectively. This approach was highly regioselective, and the transformation was achieved based on two different (Pd(ii)/Pd(iv)) and (Pd(0)/Pd(ii)) catalytic cycles.
- Das, Animesh,Jana, Akash,Maji, Biplab
-
supporting information
p. 4284 - 4287
(2020/04/27)
-
- METHOD FOR PRODUCING (METH) ACRYLATE
-
PROBLEM TO BE SOLVED: To provide a production method for obtaining (meth) acrylate in high yields, by preventing a large amount of waste from produced from by-products, like the conventional art. SOLUTION: A method for producing (meth) acrylate includes the reaction between a compound represented by the following formula (I) and an aryl alcohol. Preferably, the reaction occurs in the presence of a catalyst of at least one metal compound selected from first Group metal compounds and second Group metal compounds. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
- -
-
Paragraph 0019; 0020; 0023
(2018/12/05)
-
- CARBOXYLIC ACID ESTER PRODUCTION METHOD
-
Provided is a production method whereby corresponding carboxylic acid esters can be obtained from a variety of carboxylic acids at a high yield, even under conditions using a simple reaction operation and little catalyst and even if the amount of substrate used is theoretical. A production method for carboxylic acid ester, whereby a prescribed diester dicarbonate, carboxylic acid, and alcohol are reacted in the presence of at least one type of magnesium compound and at least one type of alkali metal compound.
- -
-
Paragraph 0071; 0072; 0074
(2019/01/04)
-
- Kinetic studies of conjugate addition of amines to allenic and acrylic esters and their correlation with antibacterial activities against Staphylococcus aureus
-
Abstract: Kinetic reactivities of various allenic and acrylic esters in conjugate addition reactions with various amines were investigated. Competition experiments showed that amines reacted selectively with allenic esters, which was also confirmed by quantitative determination of the rate constants. The antibacterial activity against Staphylococcus aureus of allenic and acrylic ester derivatives were also determined. Allenic esters were found to exhibit a higher antibacterial activity than its acrylic counterparts. A correlation between the kinetic property and the antibacterial activity suggested that a conjugate addition may involve in the antibacterial mechanism of these unsaturated esters. Graphical abstract: [Figure not available: see fulltext.].
- Kiattisewee, Cholpisit,Kaidad, Angkit,Jiarpinitnun, Chutima,Luanphaisarnnont, Torsak
-
p. 1059 - 1068
(2018/02/26)
-
- METHOD FOR PRODUCING CARBOXYLIC ACID ANHYDRIDE AND METHOD FOR PRODUCING CARBOXYLIC ACID ESTER
-
Provided is a production method whereby corresponding carboxylic acid anhydrides and carboxylic acid esters can be obtained at high yield from various carboxylic acids even without a solvent and near room temperature. A method for producing a carboxylic acid anhydride represented by formula (II), the method comprising reacting a compound represented by formula (I) and a carboxylic acid in the presence of a Group II metal compound having an ionic ligand containing an oxygen atom. A method for producing a carboxylic acid ester, the method comprising reacting a carboxylic acid anhydride produced by the aforementioned method and an alcohol. In formula (I), R1 represents a C1-20 hydrocarbon group. In formula (II), R2 represents a C1-20 hydrocarbon group.
- -
-
Paragraph 0082; 0083
(2017/04/18)
-
- PHENYL (METH)ACRYLATE PRODUCTION METHOD AND PHENYL (METH)ACRYLATE COMPOSITION
-
Provided is a method that can produce phenyl(meth)acrylate inexpensively and at high yields. The phenyl(meth)acrylate production method of the present invention reacts (meth)acrylic acid with carbonic acid diphenyl. Further, the phenyl(meth)acyrlate composition of the present invention contains 90-99.999 wt % phenyl(meth)acrylate and 0.001-10% carbonic acid diphenyl. Or, the phenyl(meth)acrylate composition of the present invention contains 90-99.999 wt % phenyl(meth)acrylate and 0.001-10 wt % of a specified compound.
- -
-
Paragraph 0094-0096
(2016/09/26)
-
- PHENYL(META)ACRYLATE PRODUCTION METHOD AND PHENYL(META)ACRYLATE COMPOSITION
-
Provided is a method that can produce phenyl(meth)acrylate inexpensively and at high yields. The phenyl(meth)acrylate production method of the present invention reacts (meth)acrylic acid with carbonic acid diphenyl. Further, the phenyl(meth)acyrlate composition of the present invention contains 90-99.999wt% phenyl(meth)acrylate and 0.001-10% carbonic acid diphenyl. Or, the phenyl(meth)acrylate composition of the present invention contains 90-99.999wt% phenyl(meth)acrylate and 0.001-10wt% of a specified compound.
- -
-
Paragraph 0190-0192
(2016/11/02)
-
- Hantzsch Ester as a Photosensitizer for the Visible-Light-Induced Debromination of Vicinal Dibromo Compounds
-
The debromination of vicinal dibromo compounds to generate alkenes usually requires harsh reaction conditions and the addition of catalysts. Just recently the visible-light-induced debromination of vicinal dibromo compounds emerged as a possible alternative to commonly used methods, but the substrate scope of this reaction is limited and a photocatalyst is necessary for the successful conversion of the starting compounds. A catalyst-free visible-light-induced debromination of vicinal dibromo compounds with a base-activated Hantzsch ester as photosensitizer is reported. The method has a wide substrate scope and a broad functional-group compatibility.
- Chen, Wenxin,Tao, Huachen,Huang, Wenhao,Wang, Guoqiang,Li, Shuhua,Cheng, Xu,Li, Guigen
-
supporting information
p. 9546 - 9550
(2016/07/14)
-
- Efficient cu-catalyzed atom transfer radical addition reactions of fluoroalkylsulfonyl chlorides with electron-deficient alkenes induced by visible light
-
Fluoroalkylsulfonyl chlorides, RfSO2Cl, in which Rf=CF3, C4F9, CF2H, CH2F, and CH2CF3, are used as a source of fluorinated radicals to add fluoroalkyl groups to electron-deficient, unsaturated carbonyl compounds. Photochemical conditions, using Cu mediation, are used to produce the respective α-chloro-β-fluoroalkylcarbonyl products in excellent yields through an atom transfer radical addition (ATRA) process. Facile nucleophilic replacement of the α-chloro substituent is shown to lead to further diverse functionalization of the products.
- Tang, Xiao-Jun,Dolbier, William R.
-
supporting information
p. 4246 - 4249
(2015/04/14)
-
- 1,4-Diazabicyclo[2.2.2]octane-Promoted Aminotrifluoromethylthiolation of α,β-Unsaturated Carbonyl Compounds: N-Trifluoromethylthio-4-nitrophthalimide Acts as Both the Nitrogen and SCF3 Sources
-
A novel difunctionalization reaction is described. It uses N-trifluoromethylthio-4-nitrophthalimide as the reagent, which serves as both the nitrogen and SCF3 sources. In the presence of DABCO (1,4-diazabicyclo[2.2.2]octane), the nitrogen and SCF3 groups can be incorporated into α,β-unsaturated carbonyl compounds easily and give versatile β-amino ketones and esters in good yields. This difunctionalization reaction features mild reaction conditions, high atom-economy, and efficient access to α-SCF3 amino acids.
- Xiao, Qing,He, Qijie,Li, Juncheng,Wang, Jun
-
supporting information
p. 6090 - 6093
(2016/01/09)
-
- Direct Photoredox-Catalyzed Reductive Difluoromethylation of Electron-Deficient Alkenes
-
Photoredox-catalyzed reductive difluoromethylation of electron-deficient alkenes was achieved in one step under tin-free, mild and neutral conditions. This protocol affords a facile method to introduce RCF2 (R=H, Ph, Me, and CH2N3) groups at sites β to electron-withdrawing groups. It was found that TTMS (tris(trimethylsilyl)silane) served nicely as both the H-atom donor and the electron donor in the catalytic cycle. Experimental and DFT computational results provided evidence that RCF2 (R=H, Ph, Me) radicals are nucleophilic in nature.
- Tang, Xiao-Jun,Zhang, Zuxiao,Dolbier, William R.
-
supporting information
p. 18961 - 18965
(2016/01/26)
-
- How much does the hybridization of a carbon atom affect the transmission of the substituent effect on the chemical shift?
-
1H and 13C NMR spectra of aryl esters of propionic acid, acrylic acid, and propiolic acid were systematically examined to find out the substituent effect on the chemical shift. The values of the chemical shift of the carbonyl carbon showed an inverse correlation with the Hammett ?3 values, and the magnitude of the slope was the largest with the propiolates. The ?± carbons of acrylates and propiolates also showed an inverse correlation with much smaller values of the slopes than those of the carbonyl carbons; but those of the propionates showed absolutely no correlation. However, the ?2 carbons of acrylates and propiolates showed normal correlation with larger values of the slopes. The signs and the magnitudes of the slopes may be understood by the transmission of the substituent electronic effect through bonds as well as through space. The propiolyloxy group also showed a significantly large effect on the 13C chemical shift values of the benzene ring.
- Jeong, Eun Jeong,Lee, In-Sook Han
-
p. 295 - 299
(2015/03/03)
-
- Synthesis and micellar behaviors of an anionic polymerizable surfactant
-
A novel anionic polymerizable surfactant sodium (5-acryloyl-2-(dodecyloxy) phenyl) methane sulfonate has been synthesized from phenol, acrylic acid and bromododecane by esterification, Frise rearrangement, sulfomethylation reaction and Williamson etherification. The parameters of the micellar behaviors are as follows: The CMC was 150 ppm at 40 °C; The surface absorption amounts Γm was 3.208 × 10-6 mol m-2; The molecular areas Am was 0.550 × 10-18m2 at the interface of air-water respectively; The aggregation number (N agg) at C = CMC of this surfactant was 12. A novel anionic polymerizable surfactant sodium (5-acryloyl-2-(dodecyloxy)phenyl) methane sulfonate has been synthesized from phenol, acrylic acid and bromododecane by esterification, Frise rearrangement, sulfomethylation reaction and Williamson etherification. The surfactantsynthesized was phenyl ether, and wasn't hydrolyzed in acidicor alkalic condition.
- Ma, Lihua,Guo, Yongjun,Feng, Rusheng,Xiang, Panpan,Li, Chunhui
-
p. 583 - 588
(2014/05/20)
-
- Metal-free oxidative cyclization of alkynyl aryl ethers to benzofuranones
-
Readily available phenols can be converted into substituted aryl alkynyl ethers, which react with an N-oxide as an oxidant and catalytic amounts of a Bronsted acid to provide benzofuranones. If non-terminal alkynyl ethers are applied, a 1,2-hydride shift takes place and phenyl acrylates are obtained. Thus activated alkynes can serve as α-oxy carbene precursors even in the absence of a metal catalyst. Copyright
- Graf, Katharina,Ruehl, Carmen L.,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
-
supporting information
p. 12727 - 12731
(2013/12/04)
-
- Selective acylation of the phenolic hydroxyl of (hydroxyalkyl)phenols by using vinyl carboxylates as acyl donors in the presence of rubidium fluoride
-
Highly selective acylation of the phenolic hydroxy group can be achieved with (hydroxyalkyl)phenols carrying both alcoholic and phenolic hydroxyls by the use of vinyl carboxylates as acyl donors in the presence of rubidium fluoride.
- Miyazawa, Toshifumi,Yamamoto, Masato,Danjo, Hiroshi
-
p. 1351 - 1354
(2013/10/01)
-
- Highly stereoselective cyclopropanation of α,β-unsaturated carbonyl compounds with methyl (diazoacetoxy)acetate catalyzed by a chiral ruthenium(II) complex
-
Tantalizing triangles: The title reaction gives bicarbonyl cyclopropane products that can lead to versatile intermediates with high yields and stereoselectivities. This system was also applied to the enantioselective total synthesis of spiro cyclopropane oxindole, an HIV-1 nonnucleoside reverse transcriptase inhibitor. Copyright
- Chanthamath, Soda,Takaki, Suguru,Shibatomi, Kazutaka,Iwasa, Seiji
-
supporting information
p. 5818 - 5821
(2013/07/11)
-
- Enantio- and diastereoselective organocatalytic α-alkylation of aldehydes with 3-substituted 2-(bromomethyl)acrylates
-
The catalytic direct α-alkylation of aldehydes with 2-(bromomethyl)acrylates has been accomplished, giving rise to α-branched and functionalized aldehydes of high diastereo- and enantiopurity. The influence of the nature of the ester group of the acrylates in reaction stereoselectivity and especially in reactivity is investigated. Optimum conditions implicate the use of phenyl acrylates in conjunction with organocatalyst 8. Application of thus obtained adducts in synthesis is illustrated with a concise stereocontrolled preparation of trisubstituted cyclopentenes.
- Jimenez, Jacqueline,Landa, Aitor,Lizarraga, Aitziber,Maestro, Miguel,Mielgo, Antonia,Oiarbide, Mikel,Velilla, Irene,Palomo, Claudio
-
experimental part
p. 747 - 753
(2012/03/26)
-
- The design and synthesis of acrylato and imino derivatives of calix[4]arene for applications in static and dynamic combinatorial libraries
-
The synthesis of novel calix[4]arene tetra-acrylates and the potential use of macrocyclic platforms in the development of static and dynamic combinatorial libraries (DCL) using reversible imine formationare described. Using such a macrocyclic platform in DCL formation results in a large number of library members while keeping the number of building blocks in the library to a minimum number.
- Le-Gresleya, Adam,Kuhnerta, Nikolai
-
experimental part
p. 61 - 67
(2010/07/03)
-
- Inactivation of GABA transaminase by 3-chloro-1-(4-hydroxyphenyl)propan-1-one
-
Previously it was found that 4-hydroxybenzaldehyde is a competitive inhibitor of GABA transaminase. Here 3-chloro-1-(4-hydroxyphenyl)propan-1-one (9), a 4-hydroxybenzaldehyde analogue, was found to inactivate potently the enzyme in a time-dependent manner. α-Ketoglutarate prevented the enzyme from inactivation, suggesting that the inactivation occurs in its active site. Several experiments indicated that the inactivation is irreversible. This study provides a novel strategy for the design of more effective inhibitors.
- Tao, Yun-Hai,Xu, Hui-Bi,Yang, Xiang-Liang
-
scheme or table
p. 731 - 734
(2009/10/02)
-
- Biofilm Resistant Polymer Materials
-
The present invention relates to compounds and materials that reduce the accumulation of microorganisms on a surface by interfering with the attachment of the organisms to the surface. The compounds and materials of the present invention are thus useful in preventing the formation of biofilms. The compounds of the present invention may be either adhered to a surface or integrated within a polymer. Surfaces coated by the present invention are resistant to biofilm formation, in part due to the smoothness of the surface coated with the present invention.
- -
-
Page/Page column 11-12
(2009/12/24)
-
- Enantioselective organocatalytic Michael additions to acrylic acid derivatives: Generation of all-carbon quaternary stereocentres
-
Acrylic esters, thioesters and N-acryloyl pyrrole have been identified as effective electrophiles in the enantioselective Michael addition reaction with β-keto ester pro-nucleophiles catalysed by a cinchona alkaloid derived bifunctional organocatalyst; enantiomeric excesses of up to 98% and yields of up to 96% can be obtained for a range of Michael acceptors and pro-nucleophiles. The Royal Society of Chemistry.
- Rigby, Caroline L.,Dixon, Darren J.
-
supporting information; experimental part
p. 3798 - 3800
(2009/02/07)
-
- O-arylation of carboxylic acids using (phenyl)[2-(trimethylsilyl)phenyl] iodonium triflate as a precursor of arynes
-
Using (phenyl)[2-(trimethylsilyl)phenyl]iodonium triflate as a precursor of arynes, Larock's method for O-arylation of carboxylic acids and arynes was developed. A variety of acids including simple aliphatic carboxylic acids, aromatic carboxylic acids, allenoic acids, and p-toluenesulfonic acid under mild reaction conditions could generate the aryl esters. Copyright Taylor & Francis Group, LLC.
- Xue, Jian,Huang, Xian
-
p. 2179 - 2185
(2008/02/05)
-
- Rational design of inhibitors of VirA-VirG two-component signal transduction
-
VirA-VirG two-component system regulates the vir (virulence) operon in response to specific host factors (xenognosins) in the plant pathogen Agrobacterium tumefaciens. Using whole cell assays, stable inhibitors inspired by the labile natural benzoxazinone inhibitor HDMBOA are developed. It is found that aromatic aldehydes represent a minimal structural unit for activity. In particular, 3-hydroxy-4,6-dimethoxy-3H-isobenzofuran-1-one (HDI) was found to have the highest activity, making it the most potent developed inhibitor of virulence gene expression in Agrobacterium.
- Maresh, Justin,Zhang, Jin,Tzeng, Yih-Ling,Goodman, Nora A.,Lynn, David G.
-
p. 3281 - 3286
(2008/02/08)
-
- Synthesis of phenyl 2-acryloyloxybornane-10-sulfonate diastereomers
-
Several routes to phenyl 2-exo- and 2-endo-acryloyloxybornane-10-sulfonate have been investigated. Preparation of the former product is complicated by concomitant formation of 10-isobornylsultone, while addition of HCl is observed when the alcohol precursors are treated with acryloyl chloride in the presence of Al2O3. An X-ray crystal structure has been determined for one of the chlorinated derivatives.
- Duggan, Andrew R.,Kaye, Perry T.,Caira, Mino R.
-
p. 744 - 747
(2007/10/03)
-
- METHOD FOR PRODUCING AROMATIC ESTER
-
PROBLEM TO BE SOLVED: To provide a method for producing a high-purity aromatic ester in a high yield without using an aqueous medium as a reaction solvent. SOLUTION: This method for producing the aromatic ester comprises reacting an organic carboxylic acid halide with a phenol in the presence of a Lewis acid in an organic solvent. The concrete example of a preferable Lewis acid is a zinc compound such as zinc chloride, zinc bromide, zinc acetate, an aluminum compound such as aluminum chloride, aluminum bromide, diethylaluminum chloride, a boron compound such as boron trifluoride, boron trichloride, a titanium compound such as titanium tetrachloride, a zirconium compound such as zirconium chloride, and a tin compound such as tin tetrachloride, tin trichloride. A (meth)acrylic acid halide is preferable as the organic carboxylic acid halide.
- -
-
Page/Page column 6-7
(2008/06/13)
-
- Exploring the scope of the 29G12 antibody catalyzed 1,3-dipolar cycloaddition reaction
-
29G12 is a murine monoclonal antibody programmed to catalyze the regio- and enantioselective 1,3-dipolar cycloaddition reaction between 4-acetamidobenzonitrile N-oxide 1a and N,N-dimethylacrylamide 2a (Toker, J. D.; Wentworth, P., Jr.; Hu, Y.; Houk, K. N.; Janda, K. D. J. Am. Chem. Soc. 2000, 122, 3244). Given the unique nature of 29G12 as a protein biocatalyst for this chemical reaction, we have investigated both the substrate specificity and mechanistic parameters of the 29G12-catalyzed process. These studies have shown that while 29G12 is specific for its dipole substrate Ia, the antibody is highly promiscuous with respect to the dipolarophiles it can process. 29G12 accepts a bulky hydrophobic dipolarophile cosubstrate, with rates of product formation up to 70-fold faster than with the original substrate 2a. In all cases, the respective isoxazoline products are produced with exquisite regio- and stereochemical control (78-98% ee). Comparison between the steady-state kinetic parameters from the 29G12-catalyzed reaction of 1a with the most efficient versus the original dipolarophile cosubstrate (2m and 2a, respectively), reveals that while the effective molarities (EM)s are almost identical (EM (2m) 26 M; EM(2a) 23 M), the affinity of 29G12 for the larger dipolarophile 2m is more than 1 order of magnitude higher than for 2a [Km(2m) 0.44 ± 0.04 mM; Km(2a) 5.8 ± 0.4 mM]. Furthermore, when 2m is the cosubstrate, the affinity of 29G12 for its dipole 1a is also greatly improved [Km(1a) 0.82 ± 0.1 mM compared to Km(1a) 3.4 ± 0.4 mM when 2a is the cosubstrate]. An analysis of the temperature dependence of the 29G12-catalyzed reaction between 1a and 2m reveals that catalysis is achieved via a decrease in enthalpy of activation (ΔΔH? 4.4 kcal mol-1) and involves a large increase in the entropy of activation (ΔΔS? 10.4 eu). The improved affinity of 29G12 for the nitrile oxide Ia in the presence of 2m, coupled with the increase in ΔΔS? during the 29G12-catalyzed reaction between 1a and 2m supports the notion of a structural reorganization of the active site to facilitate this antibody-catalyzed reaction.
- Toker, Jonathan D.,Tremblay, Martin R.,Yli-Kauhaluoma, Jari,Wentworth, Anita D.,Zhou, Bin,Wentworth Jr., Paul,Janda, Kim D.
-
p. 7810 - 7815
(2007/10/03)
-
- Antimicrobial activity of p-hydroxyphenyl acrylate derivatives
-
To estimate the antimicrobial effect of p-hydroxyphenyl acrylate (H5) derivatives on the basis of their molecular structure, the hydroxy and acryl groups of p-hydroxyphenyl acrylate were modified. The antimicrobial activity of the resulting compounds was assessed against a Gram-positive bacterium (Staphylococcus aureus), a Gram-negative bacterium (Pseudomonas aeruginosa), and fungi (Aspergillus fumigatus and Penicillium pinphilum) by the halo zone and the shake flask test. The antimicrobial activity of H5 was ascribed mainly to the acryl group. Compounds with acryl or acryloxy groups bound to the phenyl moiety were found to exhibit particularly high antimicrobial activities. The activities of phenyl acrylate and phenyl vinyl ketone were excellent as compared to aliphatic acrylates such as cyclohexyl acrylate and hexyl acrylate, indicating that the stereoelectronic effect of the phenyl group was important to the antimicrobial activity.
- Jung, Hee Kim,Park, Eun-Soo,Jae, Hun Shim,Kim, Mal-Nam,Moon, Woong-Sik,Chung, Kyoo-Hyun,Yoon, Jin-San
-
p. 7480 - 7483
(2007/10/03)
-
- Process for the conversion of aldehydes to esters
-
A process for the conversion of aldehydes to esters, specifically acrolein or methacrolein to methyl acrylate or methyl methacrylate, respectively. Essentially in the absence of water, an aldehyde is contacted with an oxidizing agent to form an intermediate and then the intermediate is contacted with a diol or an alcohol to form an ester or diester. Preferably, the oxidizing agent is also a chlorinating agent. Specifically, acrolein or methacrolein is contacted with an oxidizing/chlorinating agent, such as t-butyl hypochlorite, and the chlorinated compound is contacted with an alcohol, such as methanol, to form methyl acrylate or methyl methacrylate, respectively. Generally, the order of addition is for the oxidizing agent to be added to the aldehyde, specifically for t-butyl hypochlorite to be added to acrolein or methacrolein, and for the diol or alcohol to be added to the intermediate, specifically for the methanol to be added to the reaction product of acrolein or methacrolein and t-butyl hypochlorite. The process of the present invention can be carried out in the absence or in the presence of solvent. Generally, better methyl acrylate or methyl methacrylate yields are obtained at lower reaction temperatures.
- -
-
Page/Page column 3-4
(2010/01/31)
-
- Different reaction patterns in the Baylis-Hillman reaction of aryl aldehydes with phenyl vinyl ketone, phenyl acrylate and phenyl thioacrylate
-
In the Baylis-Hillman reaction of aryl aldehydes with phenyl vinyl ketone we have observed exclusive formation of diadducts 4, and that the yields of diadduct can reach 80% with increasing amounts of phenyl vinyl ketone. On the other hand, for phenyl acrylate and phenyl thioacrylate, only the normal Baylis-Hillman adduct was obtained. The effects of substituents were also examined and a plausible reaction mechanism is proposed for the formation of compounds 4.
- Shi, Min,Li, Chao-Qun,Jiang, Jian-Kang
-
p. 721 - 733
(2007/10/03)
-
- The reactions of aryl acrylates under Baylis-Hillman conditions
-
The use of aryl acrylates in the Baylis-Hillman reaction is reported. In contrast to their alkyl counterparts these acrylates react very rapidly with aldehydes, often yielding cyclic products arising from reaction of the initial adduct with a second molecule of aldehyde.
- Perlmutter, Patrick,Puniani, Evaloni,Westman, Gunnar
-
p. 1715 - 1718
(2007/10/03)
-
- An Approach for the Rapid Synthesis of Moderately Sized Dendritic Macromolecules
-
A general method for the synthesis of a dendrimeric series with homologous terminal groups is described.FABMS measurements confirm the molecular mass of the reported dendrimers.The result of size exclusion chromatographic (SEC) analysis correlates well with the relative molecular mass (RMM) of the early members of the series.However, deviations in measurements of molecular mass by SEC and FABMS begin to appear for larger members of the series, suggesting a more spherical conformation when the terminal group exceeds propyl.
- Twyman,lance J.,Beezer, Anthony E.,Mitchell, John C.
-
p. 407 - 412
(2007/10/02)
-
- The 'Baylis - Hillman reaction' mechanism and applications revisited
-
It is shown that reaction of aryl, benzyl, alkyl and functionalised alkyl acrylic esters with benzaldehyde, in the presence of 1,4-diazabicyclo[2.2.2] octane, strongly depends upon the electronic and steric effects of the ester part. This influence is also observed in condensation of furfuraldehyde. Moreover, for the first time, it is shown that the overall condensation is equilibrated.
- Fort, Yves,Berthe, Marie Christine,Caubere, Paul
-
p. 6371 - 6384
(2007/10/02)
-
- Preparation and Reactivities of (η3-1- and 2-Trimethylsiloxyallyl)Fe(CO2)NO Complexes. Intermediates Functioning as Equivalents of β- and α-Acyl Carbocations and Acyl Carbanions
-
(η3-1- and 2-Trimethylsiloxyallyl)Fe(CO)2NO complexes were prepared by the reaction of the corresponding siloxyallylic halides with Bu4N.These complexes reacted with both of carbon nucleophiles and carbon electrophiles preferentially at the less hindered sites of the allylic ligands.In these reactions, (η3-1-trimethylsiloxyallyl)Fe(CO)2NO complexes served as synthetically equivalent synthons for both of β-acyl carbocations and β-acyl carbanions and (η3-2-trimethylsiloxyallyl)Fe(CO)2NO complexes as both of α-acyl carbocations and α-acyl carbanions.The stereochemical courses of the reactions are described.
- Itoh, Keiji,Nakanishi, Saburo,Otsuji, Yoshio
-
p. 2965 - 2977
(2007/10/02)
-
- DABCO-Catalysed Dimerisation of Some α,β-Unsaturated Esters
-
Acrylate esters readily undergo the Baylis-Hillman reaction with aldehydes in the presence of DABCO.In the absence of aldehydes it has now been established that esters with good leaving groups undergo self condensation (Michalel addition) to afford dimers in almost quantitative yield.
- Drewes, Siegfried E.,Emslie, Neville D.,Karodia, Nazira
-
p. 1915 - 1921
(2007/10/02)
-
- FURTHER STUDY OF ESTERTIN TRICHLORIDES, Cl3SnCH2CH2CO2R. LEWIS ACIDITY TOWARDS ACETONITRILE. CRYSTAL STRUCTURE OF Cl3SnCH2CH2CO2Pr-i
-
Crystals of Cl3SnCH2CH2CO2Pr-i are orthorombic, space group P212121 with a 9.638(6), b 10.004(7) and c 12.848(8) Angstroem.The tin atom is five-coordinate with two chlorines and carbon equatorial and the remaining chlorine and the carbonyl oxygen axial, in a distorted trigonal-bipyramidal arrangement: (Sn-Cl)ax 2.389(3), average (Sn-Cl)eq 2.320(2), Sn-C 2.142(9), Sn-O 2.337(5) Angstroem.Apart from the equatorial chlorine and the terminal carbons in the isopropyl group, all non-hydrogen atoms are essentially coplanar.The molecule approaches C2v symmetry although not constrained to do so by the crystallographic space group.In MeCN solution, the compounds Cl3SnCH2CH2CO2R (I, R = Me, Pr-i, C6H4X (X = p-MeO, H, p-Cl, o-MeO) or C6H3Cl2-2,4) form as equilibrium mixtures of 1/1 and 2/1 MeCN/1 complexes; the chelate ring is broken in the 2/1 complexes.Equilibrium constants indicate that the strength of the intramolecular Sn-O coordination I increases with the electron releasing ability of the R group.
- Howie, R. Alan,Paterson, Eric S.,Wardell, James L.,Burley, Joseph W.
-
p. 301 - 308
(2007/10/02)
-
- Dehydrobromination of Some Substituted Phenyl 3-Bromopropionates and Phenyl 3-Bromothiolopropionates. Transmission of Activation Effects through Acyl Bonds
-
Thirteen aryl 3-bromopropionates and nine aryl 3-bromothiolopropionates were prepared and subjected to dehydrohalogenation with sodium 3,4-dinitrophenoxide in dry tetrahydrofuran at 34.25 deg C.The second-order rate constants for the sulfur esters were approximately 10 times those for the corresponding oxygen esters.Good Hammett plots with ρ's of +0.81+/-0.04 and 0.98+/-0.04 for the oxygen and sulfur series, respectively, were obtained by using ?n.Activation parameters were measured for two oxygen and two sulfur esters; in both bases, low (12-13 kcal/mol) activatio n enthalpies and moderately large negative (19-21 eu) activation entropies were found.At 34.25 deg C, 3'-nitrophenyl 3-bromopropionate dehydrohalogenated 14 times more rapidly than 3'-nitrophenyl 3-chloropropionate; phenyl 3-bromothiolopropionate dehydrohalogenated 11 times more rapidly than the phenyl 3-chlorothiolopropionate.The rate constant ratio for 4'-bromophenyl 3-bromopropionate vs. 4'-bromophenyl 3-bromopropionate-2-d was 1.84; the monodeuterated compound yielded olefinic product with 65percent D.H was abstracted preferentially from 4'-chlorophenyl 3-bromothiolopropionate partially deuterated in the 2-position, but no kinetic results were obtained.No evidence of reversibility was found with 2,4-dinitrophenol-d, and the addition of 2,4-dinitrophenol to kinetic mixtures had essentially no effect on the rate conatants.The results are interpreted to indicate an E2 process near the EL/E1cB borderline with the thiolo ester deviating somewhat more toward an E1cB-I process.
- Gilbert, Arthur B.,Peters, Frances B.,Johnson, H. W.
-
p. 2724 - 2728
(2007/10/02)
-
- Control of the 'Extended' E1cB Mechanism of Acyl Group Transfer in Activated Esters of Acrylic Acids
-
Aminolysis and alkaline hydrolysis of aryl propenoates are shown to proceed via a normal nucleophilic substitution mechanism.The 'extended' E1cB mechanism of hydrolysis involving attack of hydroxide ion at the β-carbon followed by expulsion of the phenolate ion from the resulting carbanion is shown not to occur with the parent propenoate.The 'extended' E1cB mechanism is taken by the hydrolysis of 2-cyano-3-(4-methoxyphenyl)propenoate esters due to the stabilising effect of the cyano-group on the intermediate carbanion.
- Douglas, Kenneth T.,Williams, Andrew
-
p. 131 - 134
(2007/10/02)
-