4100-80-5Relevant academic research and scientific papers
Carbonylative Polymerization of Epoxides Mediated by Tri-metallic Complexes: A Dual Catalysis Strategy for Synthesis of Biodegradable Polyhydroxyalkanoates
Li, Wen-Bing,Liu, Ye,Lu, Xiao-Bing,Yang, Jin-Chuang,Yang, Jun
supporting information, (2022/01/20)
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.
Synthesis of Cyclic Anhydrides via Ligand-Enabled C–H Carbonylation of Simple Aliphatic Acids
Herron, Alastair N.,Yu, Jin-Quan,Zhuang, Zhe
supporting information, p. 16382 - 16387 (2021/06/23)
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.
Thiol–Anhydride Dynamic Reversible Networks
Podgórski, Maciej,Mavila, Sudheendran,Huang, Sijia,Spurgin, Nathan,Sinha, Jasmine,Bowman, Christopher N.
supporting information, p. 9345 - 9349 (2020/04/07)
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).
(Meth) acrylic ester and manufacturing method thereof (by machine translation)
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Paragraph 0058, (2019/12/04)
(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)
METHOD FOR THE PRODUCTION OF METHYLSUCCINIC ACID AND THE ANHYDRIDE THEREOF FROM CITRIC ACID
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Page/Page column 16, (2018/04/21)
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
Continuous-Flow Production of Succinic Anhydrides via Catalytic β-Lactone Carbonylation by Co(CO)4?Cr-MIL-101
Park, Hoyoung D.,Dinca, Mircea,Román-Leshkov, Yuriy
supporting information, p. 10669 - 10672 (2018/09/06)
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.
Efficient cyclodehydration of dicarboxylic acids with oxalyl chloride
Kantin, Grigory,Chupakhin, Evgeny,Dar'in, Dmitry,Krasavin, Mikhail
supporting information, p. 3160 - 3163 (2017/07/18)
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.
MoO3-TiO2 synergy in oxidative dehydrogenation of lactic acid to pyruvic acid
Liu, Kaituo,Huang, Xiaoming,Pidko, Evgeny A.,Hensen, Emiel J. M.
, p. 3014 - 3022 (2017/07/15)
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.
Synthesis and biological evaluation of ranitidine analogs as multiple-target-directed cognitive enhancers for the treatment of Alzheimer's disease
Gao, Jie,Midde, Narasimha,Zhu, Jun,Terry, Alvin V.,McInnes, Campbell,Chapman, James M.
supporting information, p. 5573 - 5579 (2016/11/09)
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.
An Efficient One-Pot Synthesis of Bis Butenolides
Bayat, Mohammad,Fox, Joseph M.
, p. 1661 - 1664 (2016/09/23)
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.
