- Carbonylative Polymerization of Epoxides Mediated by Tri-metallic Complexes: A Dual Catalysis Strategy for Synthesis of Biodegradable Polyhydroxyalkanoates
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Polyhydroxyalkanoates (PHAs) are a unique class of commercially manufactured biodegradable polyesters with properties suitable for partially substituting petroleum-based plastics. However, high costs and low volumes of production have restricted their application as commodity materials. In this study, tri-metallic complexes were developed for carbonylative polymerization via a dual catalysis strategy, and 17 products of novel PHAs with up to 38.2 kg mol?1 Mn values were discovered. The polymerization proceeds in a sequential fashion, which entails the carbonylative ring expansion of epoxide to β-lactone and its subsequent ring-opening polymerization that occurs selectively at the O-alkyl bond via carboxylate species. The wide availability and structural diversity of epoxide monomers provide PHAs with various structures, excellent functionalities, and tunable properties. This study represents a rare example of the preparation of PHAs using epoxides and carbon monoxide as raw materials.
- Li, Wen-Bing,Liu, Ye,Lu, Xiao-Bing,Yang, Jin-Chuang,Yang, Jun
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supporting information
(2022/01/20)
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- Synthesis of Cyclic Anhydrides via Ligand-Enabled C–H Carbonylation of Simple Aliphatic Acids
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The development of C(sp3)–H functionalizations of free carboxylic acids has provided a wide range of versatile C?C and C?Y (Y=heteroatom) bond-forming reactions. Additionally, C–H functionalizations have lent themselves to the one-step preparation of a number of valuable synthetic motifs that are often difficult to prepare through conventional methods. Herein, we report a β- or γ-C(sp3)–H carbonylation of free carboxylic acids using Mo(CO)6 as a convenient solid CO source and enabled by a bidentate ligand, leading to convenient syntheses of cyclic anhydrides. Among these, the succinic anhydride products are versatile stepping stones for the mono-selective introduction of various functional groups at the β position of the parent acids by decarboxylative functionalizations, thus providing a divergent strategy to synthesize a myriad of carboxylic acids inaccessible by previous β-C–H activation reactions. The enantioselective carbonylation of free cyclopropanecarboxylic acids has also been achieved using a chiral bidentate thioether ligand.
- Herron, Alastair N.,Yu, Jin-Quan,Zhuang, Zhe
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supporting information
p. 16382 - 16387
(2021/06/23)
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- Thiol–Anhydride Dynamic Reversible Networks
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The reaction of thiols and anhydrides to form ring opened thioester/acids is shown to be highly reversible and it is accordingly employed in the fabrication of covalent adaptable networks (CANs) that possess tunable dynamic covalent chemistry. Maleic, succinic, and phthalic anhydride derivatives were used as bifunctional reactants in systems with varied stoichiometries, catalyst, and loadings. Dynamic characteristics such as temperature-dependent stress relaxation, direct reprocessing and recycling abilities of a range of thiol–anhydride elastomers, glasses, composites and photopolymers are discussed. Depending on the catalyst strength, 100 % of externally imposed stresses were relaxed in the order of minutes to 2 hours at mild temperatures (80–120 °C). Pristine properties of the original materials were recovered following up to five cycles of a hot-press reprocessing technique (1 h/100 °C).
- Podgórski, Maciej,Mavila, Sudheendran,Huang, Sijia,Spurgin, Nathan,Sinha, Jasmine,Bowman, Christopher N.
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supporting information
p. 9345 - 9349
(2020/04/07)
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- (Meth) acrylic ester and manufacturing method thereof (by machine translation)
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(Meth) acrylic acid ester of [be] hydrophobic properties. (1) (Meth) acrylic ester represented by the formula [a]. R1 Is H or methyl; R3 Alkyl, cycloalkyl, aryl or aralkyl; R21 , R22 , R23 Each independently is H, alkyl or cycloalkyl is not one of at least 2 H; Z1 The divalent chain hydrocarbon substituted of unsubstituted C1 a-20/2, 2 // hetero-substituted of unsubstituted C1 a-20 free of divalent cyclic hydrocarbon or a single bond; Z2 The divalent chain hydrocarbon of C1 c 12 2, Z3 The (R21 R22 R23 ) Coupled with a free cyclic hydrocarbon containing heteroatoms C C - C3 d 10/forming atomic group; n is an integer of 0 - 3; m is an integer of 1 - 18[Drawing] no (by machine translation)
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Paragraph 0058
(2019/12/04)
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- METHOD FOR THE PRODUCTION OF METHYLSUCCINIC ACID AND THE ANHYDRIDE THEREOF FROM CITRIC ACID
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A process for the preparation of methylsuccinic acid in any form, including its salts, its mono- and diester derivatives and the anhydride thereof, which comprises reacting citric acid or a derivative thereof in decarboxylation conditions, said process comprising (i) reacting citric acid or mono- and diester derivatives thereof in a non- aqueous solvent, specifically excluding alcohols, on a metallic catalyst at a temperature between 50 to 400°C and under a partial hydrogen pressure from 0.1 to 50 bar or (ii) reacting citric acid or any salt thereof or mono-, di- and triester derivatives thereof on a metallic catalyst in solvents comprising at least 5% water, at a temperature of from 50 to 400°C under a hydrogen partial pressure from 0.1 to 400 bar
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Page/Page column 16
(2018/04/21)
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- Continuous-Flow Production of Succinic Anhydrides via Catalytic β-Lactone Carbonylation by Co(CO)4?Cr-MIL-101
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Industrial synthesis of succinic acid relies on hydrocarbon oxidation or biomass fermentation routes that suffer from energy-costly separation processes. Here we demonstrate an alternate route to succinic anhydrides via β-lactone carbonylation by heterogeneous bimetallic ion-pair catalysis in Co(CO)4--incorporated Cr-MIL-101 (Co(CO)4Cr-MIL-101, Cr-MIL-101 = Cr3O(BDC)3F, H2BDC = 1,4-benzenedicarboxylic acid). Postsynthetically introduced Co(CO)4- facilitates CO insertion to β-lactone substrates activated by the Lewis acidic Cr(III) centers of the metal-organic framework (MOF), leading to catalytic carbonylation with activity and selectivity profiles that compare favorably to those reported for homogeneous ion-pair catalysts. Moreover, the heterogeneous nature of the MOF catalyst enables continuous production of succinic anhydride through a packed bed reactor, with room temperature β-propiolactone carbonylation activity of 1300 molAnhydride·molCo-1 over 6 h on stream. Simple evaporation of the fully converted product stream yields the desired anhydride as isolated solids, highlighting the unique processing advantages conferred by this first example of heterogeneous β-lactone carbonylation pathway.
- Park, Hoyoung D.,Dinca, Mircea,Román-Leshkov, Yuriy
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supporting information
p. 10669 - 10672
(2018/09/06)
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- MoO3-TiO2 synergy in oxidative dehydrogenation of lactic acid to pyruvic acid
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An efficient catalytic process for the oxidative dehydrogenation of biomass-derived lactic acid by earth-abundant MoO3/TiO2 mixed oxide catalysts is presented. A series of MoO3/TiO2 materials with varied MoO3 loadings were prepared and their performance in the aerobic and anaerobic conversion of lactic acid was evaluated. A strong synergistic effect between MoO3 and TiO2 components of the mixed oxide catalyst was observed. Optimum catalysts in terms of activity and pyruvic acid selectivity can be obtained by ensuring a high dispersion of MoOx species on the titania surface. Mo-oxide aggregates catalyze undesired side-reactions. XPS measurements indicate that the redox processes involving supported Mo ions are crucial for the catalytic cycle. A mechanism is proposed, in which lactic acid adsorbs onto basic sites of the titania surface and is dehydrogenated over the Mo=O acid-base pair of a vicinal tetrahedral Mo site. The catalytic cycle closes by hydrolysis of surface pyruvate and water desorption accompanied by the reduction of the Mo center, which is finally oxidized by O2 to regenerate the initial active site. Under anaerobic conditions, a less efficient catalytic cycle is established involving a bimolecular hydrogen transfer mechanism, selectively yielding propionic and pyruvic acids as the major products. The optimum catalyst is 2 wt% MoO3/TiO2 predominantly containing tetrahedral Mo species. With this catalyst the oxidative conversion of lactic acid at 200 °C proceeds with a selectivity of ca. 80% to pyruvic acid. The pyruvic acid productivity is 0.56 g g-1 h-1.
- Liu, Kaituo,Huang, Xiaoming,Pidko, Evgeny A.,Hensen, Emiel J. M.
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p. 3014 - 3022
(2017/07/15)
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- Efficient cyclodehydration of dicarboxylic acids with oxalyl chloride
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Literature examples illustrating the use of oxalyl chloride to prepare dicarboxylic acid anhydrides are surprisingly limited. At the same time, we have discovered a method involving the use of this readily available reagent which allowed the preparation of novel cyclic anhydrides where other, more conventional, methods had failed. Herein, we demonstrate that the method is applicable to a wide diversity of substrates, delivers good to excellent yields of cyclic anhydrides without chromatographic purification and can be considered a synthetic tool of choice whenever dicarboxylic acid cyclodehydration is required.
- Kantin, Grigory,Chupakhin, Evgeny,Dar'in, Dmitry,Krasavin, Mikhail
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supporting information
p. 3160 - 3163
(2017/07/18)
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- Synthesis and biological evaluation of ranitidine analogs as multiple-target-directed cognitive enhancers for the treatment of Alzheimer's disease
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Using molecular modeling and rationally designed structural modifications, the multi-target structure–activity relationship for a series of ranitidine analogs has been investigated. Incorporation of a variety of isosteric groups indicated that appropriate aromatic moieties provide optimal interactions with the hydrophobic and π–π interactions with the peripheral anionic site of the AChE active site. The SAR of a series of cyclic imides demonstrated that AChE inhibition is increased by additional aromatic rings, where 1,8-naphthalimide derivatives were the most potent analogs and other key determinants were revealed. In addition to improving AChE activity and chemical stability, structural modifications allowed determination of binding affinities and selectivities for M1–M4 receptors and butyrylcholinesterase (BuChE). These results as a whole indicate that the 4-nitropyridazine moiety of the JWS-USC-75IX parent ranitidine compound (JWS) can be replaced with other chemotypes while retaining effective AChE inhibition. These studies allowed investigation into multitargeted binding to key receptors and warrant further investigation into 1,8-naphthalimide ranitidine derivatives for the treatment of Alzheimer's disease.
- Gao, Jie,Midde, Narasimha,Zhu, Jun,Terry, Alvin V.,McInnes, Campbell,Chapman, James M.
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supporting information
p. 5573 - 5579
(2016/11/09)
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- An Efficient One-Pot Synthesis of Bis Butenolides
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3,3′,4,4′-Tetramethyl-5,5′-dioxo-2,2′-bifuran-2,2′(5H,5′H) diyl diacetate was obtained from the reaction between 2,3-dimethyl maleic anhydride and acetic anhydride in the presence of zinc in toluene. This easy synthetic route gave bis butenolide in excellent yield.
- Bayat, Mohammad,Fox, Joseph M.
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p. 1661 - 1664
(2016/09/23)
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- Nickel promoted functionalization of CO2 to anhydrides and ketoacids
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The reductive functionalization of carbon dioxide into high value organics was accomplished via the coupling with carbon monoxide and ethylene/propylene at a zerovalent nickel species bearing the 2-((di-t-butylphosphino)methyl)pyridine ligand (PN). An initial oxidative coupling between carbon dioxide, olefin, and (PN)Ni(1,5-cyclooctadiene) afforded five-membered nickelacycle lactone species, which were produced with regioselective 1,2-coupling in the case of propylene. The propylene derived nickelacycle lactone was isolated and characterized by X-ray diffraction. Addition of carbon monoxide, or a combination of carbon monoxide and diethyl zinc to the nickelacycle lactone complexes afforded cyclic anhydrides and 1,4-ketoacids, respectively, in moderate to high yields. The primary organometallic product of the transformation was zerovalent (PN)Ni(CO)2. This journal is
- Greenburg, Zoe R.,Jin, Dong,Williard, Paul G.,Bernskoetter, Wesley H.
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p. 15990 - 15996
(2015/01/08)
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- Succinic anhydrides from epoxides
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Catalysts and methods for the double carbonylation of epoxides are disclosed. Each epoxide molecule reacts with two molecules of carbon monoxide to produce a succinic anhydride. The reaction is facilitated by catalysts combining a Lewis acidic species with a transition metal carbonyl complex. The double carbonylation is achieved in single process by using reaction conditions under which both carbonylation reactions occur without the necessity of isolating or purifying the product of the first carbonylation.
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Page/Page column 24; 25; 26
(2013/07/25)
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- Synergy between the metal nanoparticles and the support for the hydrogenation of functionalized carboxylic acids to diols on Ru/TiO2
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Ruthenium nanoparticles supported on titania are over three times more active than conventional ruthenium on carbon for the hydrogenation of lactic acid. This superior catalytic activity can be due to a combined action of small ruthenium nanoparticles and the titania support.
- Primo, Ana,Concepcion, Patricia,Corma, Avelino
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scheme or table
p. 3613 - 3615
(2011/04/25)
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- Catalytic double carbonylation of epoxides to succinic anhydrides: Catalyst discovery, reaction scope, and mechanism
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The first catalytic method for the efficient conversion of epoxides to succinic anhydrides via one-pot double carbonylation is reported. This reaction occurs in two stages: first, the epoxide is carbonylated to a β-lactone, and then the β-lactone is subsequently carbonylated to a succinic anhydride. This reaction is made possible by the bimetallic catalyst [(CITPP)Al(THF)2]+[Co(CO)4]- (1; CITPP = meso-tetra(4-chlorophenyl)porphyrinato; THF = tetrahydrofuran), which is highly active and selective for both epoxide and lactone carbonylation, and by the identification of a solvent that facilitates both stages. The catalysis is compatible with substituted epoxides having aliphatic, aromatic, alkene, ether, ester, alcohol, nitrile, and amide functional groups. Disubstituted and enantiomerically pure anhydrides are synthesized from epoxides with excellent retention of stereochemical purity. The mechanism of epoxide double carbonylation with 1 was investigated by in situ IR spectroscopy, which reveals that the two carbonylation stages are sequential and non-overlapping, such that epoxide carbonylation goes to completion before any of the intermediate β-lactone is consumed. The rates of both epoxide and lactone carbonylation are independent of carbon monoxide pressure and are first-order in the concentration of 1. The stages differ in that the rate of epoxide carbonylation is independent of substrate concentration and first-order in donor solvent, whereas the rate of lactone carbonylation is first-order in lactone and inversely dependent on the concentration of donor solvent. The opposite solvent effects and substrate order for these two stages are rationalized in terms of different resting states and rate-determining steps for each carbonylation reaction.
- Rowley, John M.,Lobkovsky, Emil B.,Coates, Geoffrey W.
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p. 4948 - 4960
(2008/02/03)
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- Syntheses, in vitro antibacterial and cytotoxic activities of a series of 3-substituted succinimides
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We have synthesized a series of 3-substituted succinimides and their in vitro antibacterial activities have been tested towards Gram-positive and Gram-negative bacteria from the ATCC collection. Some of them possess significant antibacterial activity against Gram-positive organisms (Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212) but all are poorly active or inactive against Gram-negative organisms (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853). The compounds with the lowest minimal inhibitory concentrations (esters of 3-hydroxy succinimides) are also the most cytotoxic against green monkey Vero cell line (ATCC CCL-81) and could explain that perhaps apoptosis should be implicated in eukaryotic cell cytotoxicity of succinimides.
- Zentz, Frederic,Le Guillou, Regis,Labia, Roger,Sirot, Danielle,Linard, Boris,Valla, Alain
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p. 879 - 886
(2007/10/03)
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- Catalytic carbonylation of β-lactones to succinic anhydrides
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A well-defined,highly active and selective catalyst for the synthesis of succinic anhydrides from CO and β-lactones is reported. At 200 psi of CO, the catalyst [(N,N′-bis(3,5-di-tert-butylsalicylidene)phenylenediamino)Al(THF)2][Co(CO)4] carbonylates β-propiolactones to succinic anhydrides in high yield. (R)-β-Butyrolactone is carbonylated to (S)-methylsuccinic anhydride with clean inversion of stereochemistry, while cis-2,3-dimethyl-β-propiolactone yields exclusively trans-2,3-dimethylsuccinic anhydride. These data are consistent with a mechanism involving nucleophilic attack by [Co(CO)4]- on the β carbon of the lactone, followed by CO insertion and anhydride formation. Copyright
- Getzler, Yutan D. Y. L.,Kundnani, Vinod,Lobkovsky, Emil B.,Coates, Geoffrey W.
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p. 6842 - 6843
(2007/10/03)
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- Synthesis of Small-Medium Ring Thioanhydrides
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Reaction of five-membered ring anhydrides with sodium sulfide has previously been employed for synthesis of the corresponding thioanhydrides in low yields.Re-examination of the stoichiometry reveals reaction of cyclic anhydride with sodium sulfide (2:1 respectively), affords the thioanhydride accompanied by the corresponding dicarboxylate in a 1:1 molar ratio.The mechanistic pathway for this reaction has also been elucidated.Optimization of reaction conditions has resulted in the synthesis of a variety of four to seven-membered ring thioanhydride in yields approaching theoretical.
- Kates, Michael J.,Schauble, J. Herman
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p. 971 - 978
(2007/10/02)
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- Synthesis and spectroscopic characterisation of 13C-labelled ubiquinone-0 and ubiquinone-10
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(1-13C)-, (2-13C)-, (3-13C)-, (3-13CH3)-, (4-13C)-, and (13CH3O)2-ubiquinone-10 and the corresponding (1-13C)-, (6-13C)-, (5-13C)-, (5-13CH3)-, (4-13C)-, and (13CH3O)2-ubiquinone-0 have been synthesised from simple labelled starting materials via a single reaction scheme.The ubiquinones have been characterised using mass spectrometry, 1H NMR and 13C NMR.The spectroscopic results indicate that, within experimental error, the syntheses have been accomplished without scrambling or dilution of label.All labelled ubiquinones have been synthesised on a decigram scale.
- Liemt, W. B. S. van,Steggerda, W. F.,Esmeijer, R.,Lugtenburg, J.
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p. 153 - 162
(2007/10/02)
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- CONFORMATION OF SUCCINIC ACID DERIVATIVES BY DOUBLE 13C-LABELLING
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Three-bonded carbon/carbon couplings (3Jcc) are used, in conjunction with MM2 calculations, to examine conformational equilibria in several di-13C-labelled succinic acid derivatives.
- Menger, F.M.,Lee, L. H.
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p. 757 - 760
(2007/10/02)
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- Effect of Ligand on Ring Contraction of Six-Membered Nickel-Containing Cyclic Esters, , to Their Five-Membered-Ring Isomers, . Kinetic and Thermodynamic Control of Asyammetric Induction by Chiral Diphosphines in the Ring Contraction
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Ring contraction of (1) to (2) is accelerated by coordination of bulky ligands: coordination of a bulky diphosphine like 1,2-bis(diphenylphosphino)ethane (dpe) causes an extensive ring contraction to afford (dpe).Use of a chiral diphosphine affords a mixture of unequal amounts of diastereomers (chiral diphosphine)-(R) ((R)-2) and (chiral diphosphine)-(S)- ((S)-2).When (S,S)-chiraphos is used, (R)-2 is kinetically favored, but it isomerizes to thermodynamically favored (S)-2 obeying the first-order kinetics.The equilibrated reaction mixture after the isomerization contains ((S,S)-chiraphos) in 54percent diastereomer excess at 24 deg C, and the kinetic and thermodynamic parameters for the R to S isomerization are as follows: ΔH = 93 +/- 2 kJ/mol, ΔS = -8 +/- 6 J/(K mol), ΔG = 95 kJ/mol, ΔH = 13 +/- 2 kJ/mol, ΔS = 54 +/- 6J (K mol), and ΔG = -3.0 kJ/mol at 24 deg C.Use of (R,R)-dipamp gives a result opposite to that of (S,S)-chiraphos concerning the kinetically and thermodynamically favored species.Data obtained by use of (R)-prophos, trans-cypenphos, and trans-renorphos are also given.The kinetic and thermodynamic control of the asymmetry can be explained by considering the effects of arrangement of two phenyl groups bonded to each phosphorous atom of the diphosphine ligands on the metallacycle entity.
- Yamamoto, Takakazu,Sano, Kenji,Yamamoto, Akio
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p. 1092 - 1100
(2007/10/02)
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- Selectivity of Radical Formation in the Reaction of Carbonyl Compounds with Manganese(III) Acetate
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The selectivity of radical generation in the oxidation of carbonyl compounds by manganese(III) has been studied in two ways.Competitive reaction of acetic and propionic acids under conditions in which the resultant radicals are trapped efficiently by an alkene suggests that propionic acid reacts some 3.8 times more readily than does acetic acid.Oxidation of butanone under similar conditions gives products in the formation of which reaction has occurred 2.9 times more readily at C-3 of butanone than at C-1.However, this ratio reflects a combination of chain propagation and of initiation by manganese(III) oxidation.When propagation is effectively eliminated, the C-1 position is the more reactive.The significance of these observations on the mechanism of oxidation of carbonyl compounds by manganese(III) is discussed.It is suggested that enol radical-cations can be formed in the reaction but that these do not give carbonyl-stabilised radicals by deprotonation.
- Midgley, Gary,Thomas, C. Barry
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p. 1103 - 1108
(2007/10/02)
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- Quantitative Evaluation of the gem-Dimethyl Effect on the Succinic Acid Anhydride Equilibrium. Conformations of the Acids and Anhydrides by Empirical Force Field Calculations
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In order to evaluate quantitatively the gem-dimethyl effect on the succinic acid anhydride equilibrium, the conformations of succinic acid and its 2-methyl-, racemic 2,3-dimethyl-, tetramethyl-, and racemic 2,3-di-t-butyl-derivatives have been calculated by means of Allinger's 1977 empirical force field.An extension of the field was developed to calculate the conformations of the respective anhydrides.The calculated preferred conformations compare well with existing experimental data.No low-energy hydrogen-bonded minima for the acids were obtained.Increased substitution in the acids caused conformational changes facilitating ring closure: smaller torsion angles of conformations with gauche carboxy groups, favourable bond length and angle deformations, and a reduced number of preferred conformations.In the anhydrides, substitution leads to a twist around the C(2)-C(3) bond of the ring.The ΔΔH values estimated for the diacid anhydride equilibria agree well with experimental data in water indicating that the main cause of the observed gem-dimethyl effect in the anhydrides is relief of intramolecular strain arising on substitution in the acids.
- Ivanov, Petko M.,Pojarlieff, Ivan G.
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p. 245 - 250
(2007/10/02)
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- Preparation of Ni- or Pt-Containing Cyclic Esters by Oxidative Addition of Cyclic Carboxylic Anhydrides and Their Properties
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Metal containing cyclic ester complexes, L (L=1,2-bis(diphenylphosphino)ethane (dpe) or 2,2'-bipyridine (bpy); R1, R2=H or CH3) and Ln )L=tricyclohexylphosphine (PCy3) or dpe; n=1 or 2), have been prepared by oxidative addition of cyclic carboxylic anhydrides to zero-valent metal complexes.These complexes have been characterized by elemental analysis and spectroscopies (IR as well as 1H-, 13C1H>-, and 31P1H>-NMR) and chemical rectivities.Rate of the oxidative addition of succinic anhydride to Ni(bpy)(cod) (cod=1,5-cyclooctadiene) is expressed by a second order rate equation, R=k, and temperature dependence of k gives the activation energy of 68 kJ mol-1.The reaction of methylsuccinic anhydride with Ni(cod)2 in the presence of tertiary phosphine or bpy affords two isomers, Ln and Ln, corresponding to two modes of C-O bond cleavage in methylsuccininc anhydride promoted by Ni; dependence of the ratio between the two isomers on the kind of ligand added and reaction conditions has been examined.
- Sano, Kenji,Yamamoto, Takakazu,Yamamoto, Akio
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p. 2741 - 2747
(2007/10/02)
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- PREPARATION OF SEVERAL NEW Ni- OR Pd-CONTAINING CYCLIC AMIDE AND ESTERS, (PR3)nNi(CH2CH2CH2COZ) (Z=NH, O) AND PCy3Pd(CH2CH2CH2COO), AND RING CONTRACTION OF THE SIX-MEMBERED Ni-CONTAINING CYCLIC ESTER TO ITS FIVE-MEMBERED ISOMER
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New metallacyclic amide and esters (PCy3Ni(CH2CH2CH2CONH), (PR3)nNi(CH2CH2CH2COO), PCy3Pd(CH2CH2CH2COO) ) have been prepared by reactions of zero-valent nickel and palladium complexes with unsaturated amide and acid.The 6-membered Ni-containing cyclic ester undergoes a ring contraction reaction to a 5-membered isomer.
- Sano, Kenji,Yamamoto, Takakazu,Yamamoto, Akio
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p. 695 - 698
(2007/10/02)
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- Process for the production of 3-substituted-2,5-dioxo-tetrahydrofuran
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Process for the production of 3-substituted-2,5-dioxo-tetrahydrofuran which involves converting diketene or a substituted diketene in the presence of a catalytic quantity of a carbonyl complex or of a mixture of two carbonyl complexes of metals of the VIIIth group with carbon monoxide and hydrogen at an elevated temperature and an elevated pressure.
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- Ashless additives for lubricating compositions
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Superior ashless additives for lubricants are prepared by a process comprising first introducing a petroleum sulfonic acid and a polyamine to a reaction zone and subsequently introducing a cyclic anhydride of a dicarboxylic acid into the reaction zone. In another embodiment, the solids content of the additives is reduced to acceptable levels by removal of free SO2 from the petroleum sulfonic acid prior to preparing the additive. Lubricating oil compositions containing these ashless additives are also provided.
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