- A water-stable metal-organic framework: serving as a chemical sensor of PO4 3– and a catalyst for CO2 conversion
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A new 2D Eu-BTB framework (1) with stratified gridding structure of about 14.6 ?×16.9 ? was synthesized and characterized. Compound 1 displays excellent water stability with the pH 2–12. The luminescent investigations suggest that 1 could represent a chemical sensor of PO4 3- with high sensitivity and selectivity. Importantly, 1 as a sensor of PO4 3- can be reused at least five times. On the other hand, the catalytic investigations of 1 were carried out, indicating that 1 could be demonstrated as a recyclable catalyst for CO2 conversion with epoxides.
- Zhai, Bin,Xu, Hang,Li, Zhong-Yi,Cao, Chun-Shuai,Zhao, Bin
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- Robust Anionic LnIII-Organic Frameworks: Chemical Fixation of CO2, Tunable Light Emission, and Fluorescence Recognition of Fe3+
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With the aim of exploring and enriching nanocaged functional platforms of lanthanide-organic frameworks, the subtle combination of [Ln2(CO2)8] secondary building units and [Ln(CO2)4] units by employing the hexacarboxylic acid of 4,4′,4″-(pyridine-2,4,6-triyl)tris(1,3-benzenedicarboxylic acid) (H6PTTBA) successfully realized the self-assembly of highly robust multifunctional {LnIII2}LnIII-organic anionic skeletons of {(Me2NH2)[Ln3(PTTBA)2]·xDMF·yH2O}n (1-Ln), which had remarkable intrinsic nature of high thermal and water stability, large permanent porosity, interconnected nanocaged void volume, and high specific surface area. Here, only the Eu-based framework of 1-Eu was taken as one representative to discuss in detail. Gas-sorption experiments showed that the activated solvent-free 1-Eu framework possessed the outstanding ability to separate the mixed gases of CO2/CH4 (50:50, v/v) with an ideal adsorbed solution theory selectivity of 14. Furthermore, 1-Eu was an efficient and recycled catalyst for the chemical cycloaddition of CO2 and epoxides into their corresponding carbonates, which possessed a better catalytic performance than the documented unique Eu3+-organic framework of [Eu(BTB)(phen)] and could be widely applied in industry because of its simple synthetic conditions and high yield. In the meantime, adjustable emission colors devoted by the efficient Tb3+ → Eu3+ energy transfer confirmed that Eux/Tb1-x-organic framework could be taken as a good substitute for barcode materials by changing the ratio of Eu3+ and Tb3+. Moreover, quantitative luminescence titration experiments exhibited that 1-Eu possessed good selectivity for the identification of Fe3+ in aqueous solution by fluorescence quenching with a low limit of detection value of 6.32 × 10-6 M.
- Chen, Hongtai,Fan, Liming,Lv, Hongxiao,Zhang, Xiutang
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- A Bifunctional Europium-Organic Framework with Chemical Fixation of CO2 and Luminescent Detection of Al3+
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A novel three-dimensional lanthanide-organic framework {[Eu(BTB)(phen)]·4.5DMF·2H2O}n (1) has been synthesized. Structural characterization suggests that framework 1 possesses one-dimensional channels with potential pore volume, and the large channels in the framework can capture CO2. Interestingly, investigations on the cycloaddition reaction of CO2 and epoxides reveal that compound 1 can be considered as an efficient catalyst for CO2 fixation with epoxides under 1 atm pressure. Importantly, 1 can be reused at least five times without any obvious loss in catalytic activity. Furthermore, the luminescent explorations of 1 reveal that 1 can act as a recyclable sensor of Al3+, and the corresponding detection limit can reach 5 × 10-8 M (1.35 ppb), which is obviously lower than the United States Environmental Protection Agency's recommended level of Al3+ in drinking water (200 ppb). These results show that 1 has a level of sensitivity higher than that of other reported MOF-based sensors of Al3+.
- Xu, Hang,Zhai, Bin,Cao, Chun-Shuai,Zhao, Bin
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- Solvent-dependent variations of both structure and catalytic performance in three manganese coordination polymers
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Three new manganese 4′-(3,5-dicarboxyphenyl)-2,2′:6′,2′′′-terpyridine (H2DATP) metal-organic framework materials have been generated through regulating the ratios of a binary solvent mixture (DMA/H2O) under solvothermal conditions. Compound 1 {[Mn2(DATP)(HDATP)(H2O)4](OH)·10H2O}n displaying a one-dimensional (1D) chainlike structure was crystallized from the DMA/H2O mixture with a molar ratio of 1:1, while the two-dimensional (2D) layer species, {[Mn(DATP)(H2O)]·2H2O}n (2) was produced by increasing the ratio of DMA/H2O to 5:1. Interestingly, the crystallization in pure DMA yields a three-dimensional (3D) interpenetrating network {[Mn(DATP)]·4H2O}n (3), featuring higher solvent stability and pH stability than compounds 1 and 2. It is proved that solvent not only influences the structural transformation process of crystals but also has a significant effect on their properties. These three compounds present different catalytic performances in the CO2 cycloaddition to epoxides with various substituent groups into corresponding cyclic carbonates, and only 3 can serve as an efficient and recyclable catalyst at mild temperature.
- Kang, Xiao-Min,Wang, Wen-Min,Yao, Lin-Hong,Ren, Hong-Xia,Zhao, Bin
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- Nanochannel-based heterometallic {ZnIIHoIII}-organic framework with high catalytic activity for the chemical fixation of CO2
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The exquisite combination of ZnIIand HoIIIgenerated the highly robust [ZnHo(CO2)6(OH2)]-based heterometallic framework of {[ZnHo(TDP)(H2O)]·5H2O·3DMF}n(NUC-30, H6TDP = 2,4,6-tri(2′,4′-dicarboxyphenyl)pyridine), which featured outstanding physicochemical properties, including honeycomb nanochannels, high porosity, large specific surface area, the coexistence of highly open Lewis acid-base sites, good thermal and chemical stability, and resistance to most organic solvents. Due to its extremely unsaturated metal tetra-coordinated Zn(ii) ions, hepta-coordinated Ho(iii) and high faveolate void volume (61.3%), the conversion rate of styrene oxide and CO2into cyclic carbonates in the presence of 2 mol% activatedNUC-30and 5 mol%n-Bu4NBr reached 99% under the mild conditions of 1.0 MPa and 60 °C. Furthermore, the luminescence sensing experiments proved thatNUC-30could be used as a fast, sensitive and highly efficiency sensor for the detection of Fe3+in aqueous solution. Therefore, these results prove that nanoporous MOFs assembled from pyridine-containing polycarboxylate ligands have wide applications, such as catalysis and as luminescent materials.
- Zhang, Tao,Chen, Hongtai,Lv, Hongxiao,Li, Qiaoling,Zhang, Xiutang
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- A porous Er(III)–organic framework as a highly efficient catalyst for chemical fixation of CO2 and treatment activity on senile deafness via inducing the cochlear hair cell apoptosis
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A microporous Er(III)-based metal–organic framework (MOF), whose chemical formula can be written as {[Er(TCPB)(H2O)]·dioxane·0.5H2O}n, has been formed from the tripodal ligand 1,3,5-tris(4-carbonylphenyloxy)benzene (H3TCPB) by solvothermal synthesis and determined by the single crystal X-ray diffraction and the elemental analysis. With the aid of microporous framework and abundant catalytic sites of open Er(III) sites, the activated 1 is a special catalyst for the synthesis of cyclic carbonates from carbon dioxide and epoxy compounds under the cocatalyst TBAB and gently solvent-less conditions. The treatment activity of the compound on the senile deafness, as well as the influence of the compound on the cochlear hair cell death was explored. Firstly, the cell apoptosis of the cochlear hair cells was estimated via CCK-8 assay. Next, the activation of the caspase-3,8 was evaluated with western blot.
- Sun, Xiao-Yan,Li, Jun-Nan,Dong, Gui-Mei,Tao, Yan-Li,Chen, Yao,Yang, Shu-Qin
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- Interpenetrating Metal-Metalloporphyrin Framework for Selective CO2 Uptake and Chemical Transformation of CO2
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Herein we report a robust primitive cubic (pcu)-topology metal-metalloporphyrin framework (MMPF), MMPF-18, which was constructed from a ubiquitous secondary building unit of a tetranuclear zinc cluster, Zn4(μ4-O)(-COO)6, and a linear organic linker of 5,15-bis(4-carboxyphenyl)porphyrin (H2bcpp). The strong π-π stacking from porphyrins and the lengthy H2bcpp ligand affords a 4-fold-interpenetrating network along with reduced void spaces and confined narrow channels. Thereby, MMPF-18 presents segmented pores and high-density metalloporphyrin centers for selective CO2 uptake over CH4 and size-selective chemical transformation of CO2 with epoxides forming cyclic carbonates under ambient conditions.
- Gao, Wen-Yang,Tsai, Chen-Yen,Wojtas, Lukasz,Thiounn, Timmy,Lin, Chu-Chieh,Ma, Shengqian
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- An Uncommon Carboxyl-Decorated Metal–Organic Framework with Selective Gas Adsorption and Catalytic Conversion of CO2
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A new three-dimensional (3D) framework, [Ni(btzip)(H2btzip)]?2 DMF?2 H2O (1) (H2btzip=4,6-bis(triazol-1-yl)isophthalic acid) as an acidic heterogeneous catalyst was constructed by the reaction of nickel wire and a triazolyl-carboxyl linker. Framework 1 possesses intersected 2D channels decorated by free COOH groups and uncoordinated triazolyl N atoms, leading to not only high CO2 and C2H6 adsorption capacity but also significant selective capture for CO2 and C2H6 over CH4 and CO in 273–333 K. Moreover, 1 reveals chemical stability toward water. Grand Canonical Monte Carlo simulations confirmed the multiple CO2- and C2H6-philic sites. As a result of the presence of accessible Br?nsted acidic COOH groups in the channels, the activated framework demonstrates highly efficient catalytic activity in the cycloaddition reaction of CO2 with propylene oxide/4-chloromethyl-1,3-dioxolan-2-one/3-butoxy-1,2-epoxypropane into cyclic carbonates.
- Li, Yong-Zhi,Wang, Hai-Hua,Yang, Hong-Yun,Hou, Lei,Wang, Yao-Yu,Zhu, Zhonghua
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- A robust indium-porphyrin framework for CO2 capture and chemical transformation
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An indium based metal-porphyrinic framework, denoted NUPF-3, was prepared based on a new amido-decorated porphyrin ligand. NUPF-3 possesses a rarely seen 4-fold interpenetrated pts framework with segmented pores and dense metalloporphyrin central sites. The structure can retain its crystallinity in commonly used solvents, as well as acidic/alkaline solutions with pH ranging from 1 to 12 for 48 h, exhibiting high chemical stability. Meanwhile, thermal analysis reveals that NUPF-3 possesses relatively high thermal stability. Owing to the presence of amido groups, structural interpenetration and a charged framework, NUPF-3 exhibits relatively high CO2 uptake. Moreover, NUPF-3 could be used as a good heterogeneous catalyst for cycloaddition of CO2 and epoxides, under relatively mild conditions, with good recyclability.
- Xu, Lei,Zhai, Meng-Ke,Lu, Xin-Chao,Du, Hong-Bin
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- Heterometallic {ZnEu}-metal-organic framework for efficient chemical fixation of CO2
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Based on a ligand-directed synthetic strategy, the acidic solvothermal reaction of ZnO, Eu2O3, and 4,4′,4″-(pyridine-2,4,6-triyl)tri(1,3-benzenedicarboxylic acid) (H6PTTBA) generated a targeted robust double-walled honeycomb material {[EuIIIZnII(HPTTBA)(H2O)]·4DMF·3H2O}n (simplified as NUC-9), which featured excellent characteristics such as dual tubular nanochannels, high porosity, specific surface area, abundant exposed active metal sites, etc. Although both types of nano-channels (I and II) alternately arranged in the lattice and shaped by six rows of [EuIIIZnII(CO2)6(H2O)] SBUs possessed an equal amount of exposed active metal sites, they could be differentiated according to the discrepant inner surface functionalized by free carboxyl oxygen atoms or coordinated aqueous molecules. Moreover, an activated sample of NUC-9 exhibited better catalytic performance than documented Zn- or Eu-based MOFs for the chemical transformation of various epoxides into the related carbonates under comparatively mild conditions of 1 atm CO2 flow and 70 °C, which should be ascribed to the unsaturated Zn2+ and Eu3+ ions acting as strong Lewis acid sites and free carboxyl oxygen atoms as basic sites synergistically polarizing and activating the substrates of epoxides and CO2 and consequently promoting the reaction. Furthermore, the water-resistant framework of NUC-9 could selectively and sensitively discriminate Fe3+ in aqueous solution according to the fluorescence quenching effect. In addition, it is worth mentioning that the successful self-assembly of NUC-9 provides an effective synthetic technique by employing the designed favorable organic ligand for achieving the targeted functional model of MOFs. This journal is
- Chen, Hongtai,Fan, Liming,Lv, Hongxiao,Zhang, Xiutang
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- 6s-3d {Ba3Zn4}-Organic Framework as an Effective Heterogeneous Catalyst for Chemical Fixation of CO2and Knoevenagel Condensation Reaction
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The exquisite combination of Ba2+ and Zn2+ with the aid of 2,4,6-tri(2,4-dicarboxyphenyl)pyridine (H6TDP) under the condition of solvothermal self-assembly generates one highly robust [Ba3Zn4(CO2)12(HCO2)2(OH2)2]-organic framework of {[Ba3Zn4(TDP)2(HCO2)2(OH2)2]·7DMF·4H2O}n (NUC-27), in which adjacent 2D layers are interlaced via hydrogen-bonding interactions to form a 3D skeleton with peapod-like channels and nano-caged voids. It is worth emphasizing that both Ba2+ and Zn2+ ions in NUC-27 display the extremely low coordination modes: hexa-coordinated [Ba(1)] and tetra-coordinated [Ba(2), Zn(1), and Zn(2)]. Furthermore, to the best our knowledge, NUC-27 is one scarcely reported 2D-based nanomaterial with an unprecedented Z-shaped hepta-nuclear heterometallic cluster of [Ba3Zn4(CO2)12(HCO2)2(OH2)2] as SBUs, which not only has plentiful low-coordinated open metal sites but also has the excellent physicochemical properties including omni-directional opening pores, ultrahigh porosity, larger specific surface area, and the coexistence of Lewis acid-base sites. Just as expected, thanks to its rich active metal sites and pyridine groups as strong Lewis acid-base roles, completely activated NUC-27 displays high catalytic efficiency on the chemical transformation of epoxides with CO2 into cyclic carbonates under mild conditions and effectively accelerates the reaction process of Knoevenagel condensation.
- Chen, Hongtai,Fan, Liming,Hu, Tuoping,Zhang, Xiutang
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- Efficient cycloaddition of epoxides and carbon dioxide over novel organic-inorganic hybrid zeolite catalysts
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Organic-inorganic hybrid zeolites with the MFI-type lamellar structure serve as efficient solid Lewis base catalysts for solvent-free synthesis of a variety of cyclic carbonates from corresponding epoxides and carbon dioxide. The ion-exchange with iodide, in particular, renders these materials an excellent catalytic activity and good recyclability.
- Li, Chen-Geng,Xu, Le,Wu, Peng,Wu, Haihong,He, Mingyuan
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- In Situ Thermal Solvent-Free Synthesis of Zeolitic Imidazolate Frameworks with High Crystallinity and Porosity for Effective Adsorption and Catalytic Applications
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A facile and eco-friendly in situ thermal (IST) method was developed to synthesize zeolitic imidazole frameworks based on a 2-methylimidazole (2-MIM) linker (ZIF-67, ZIF-8, and Zn/Co-ZIF). A single-step and a short processing time with the lowest precursor ratio (M/L) and solvent-free provided an advantage of the IST method over the reported traditional synthesis procedures. A variety of synthesis parameters, including temperature, time, precursor, and gas atmosphere, were optimized to obtain excellent crystalline and porosity properties. In the following, different characterization techniques were comprehensively applied to verify the properties of the synthesized materials. Moreover, the beneficial chemical and physical properties of the synthesized material exhibited potential application for adsorption and catalysis. Overall, the IST method approach is a novel ZIF synthesis procedure generating high porous crystalline ZIFs. The IST is a green strategy avoiding solvent, activation, or post-treatment to remove unreacted residual, side-product, and guest molecules from the product. Additionally, the single-step IST process showed scalability for large-scale material synthesis.
- Wang, Jichao,Chaemchuen, Somboon,Klomkliang, Nikom,Verpoort, Francis
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- MANUFACTURING METHOD OF MONOCHLOROETHYLENE CARBONATE
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PROBLEM TO BE SOLVED: To provide a manufacturing method of industrial monochloroethylene carbonate by carrying out a photoreaction between ethylene carbonate and chlorine gas. SOLUTION: A manufacturing method of monochloroethylene carbonate is characterized in that by using a flow type photochlorination apparatus that comprises a reaction case for reacting a liquid while supplying liquid, a support stage for supporting by tilting the reaction case in such a way that the liquid flows through its own weight, a light irradiation section for transmitting light for performing a photochlorination reaction by irradiating light on the reaction case, and a temperature control unit for carrying out the photochlorination reaction by controlling the temperature of the reaction case on the reaction case, ethylene carbonate is introduced from the liquid supply part into each channel groove, chlorine gas is introduced into the gas circulation part from the gas supply port, and light is radiated from the light irradiation section is provided, and thereby the problem was solved. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2022,JPOandINPIT
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Paragraph 0034-0044
(2021/11/05)
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- One Robust Microporous TmIII-Organic Framework for Highly Catalytic Activity on Chemical CO2Fixation and Knoevenagel Condensation
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In terms of documented references, multifunctional MOFs with high catalytic performance could be constructed from the combination of metal cations and polycarboxyl-pyridine ligands, which could efficiently endow crystallized porous frameworks with the coexisting Lewis acid-base properties. Thus, by employing a ligand-directed synthetic strategy, the exquisite combination of wave-like inorganic chains of [Tm(CO2)3(OH2)]n and mononuclear units of [Tm(CO2)4(OH2)2] with the aid of the specially designed ligand of 2,6-bis(2,4-dicarboxylphenyl)-4-(4-carboxylphenyl)pyridine (H5BDCP) generates one highly robust microporous framework of {(Me2NH2)[Tm3(BDCP)2)(H2O)3]·4DMF·H2O}n (simplified as NUC-25), which contains near-rectangular nanochannels and large solvent-residing voids. Furthermore, the activated state of NUC-25 with the removal of associated water molecules is a rarely reported bifunctional heterogeneous catalyst due to the coexistence of Lewis acid-base sites including 6-coordinated Tm3+ ions, uncoordinated carboxyl oxygen atoms, and Npyridine atoms. Just as expected, NUC-25 exhibits greatly high catalytic activity for the cycloaddition reaction of epoxides with CO2 into alkyl cyclic carbonates under bland solvent-free conditions, which should be ascribed to the polarity of nitrogen-containing pyridine heterocycles as Lewis base sites on the inner surface of nano-caged voids except for recognized Lewis acid sites of rare earth cations. Moreover, the excellent pore-size-dependent catalytic property for Knoevenagel condensation reactions confirms that NUC-25 can be viewed as a recyclable bifunctional heterogeneous catalyst. Therefore, these results strongly demonstrate that microporous MOFs assembled from pre-designed polycarboxyl-heterocyclic ligands display better catalytic performance not only for chemical CO2 fixation but also for Knoevenagel condensation reactions.
- Chen, Hongtai,Hu, Tuoping,Fan, Liming,Zhang, Xiutang
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p. 1028 - 1036
(2021/02/05)
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- V= O Functionalized {Tm2}-Organic Framework Designed by Postsynthesis Modification for Catalytic Chemical Fixation of CO2and Oxidation of Mustard Gas
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In terms of recently documented references, the introduction of V= O units into porous MOF/COF frameworks can greatly improve their original performance and expand their application prospects due to a change in their electronegativity. In this work, by a cation-exchange strategy, a consummate combination of separate 4f [Tm2(CO2)8] SBUs and 3d [VIVO(H2O)2] units generated the functionalized porous metal-organic framework {(Me2NH2)2[VO(H2O)][Tm2(BDCP)2]·3DMF·3H2O}n (NUC-11), in which [Tm2(CO2)8] SBUs constitute the fundamental 3D host framework of {[Tm2](BDCP)2}n along with [VIVO(H2O)2] units being further docked on the inner wall of channels by covalent bonds. Significantly, NUC-11 represents the first example of V= O modified porous MOFs, in which uncoordinated carboxylic groups (-CO2H) further grasp the functional [VIVO(H2O)2] units on the initial basic skeleton along with the formation of covalent bonds as fixed ropes. Furthermore, activated samples of NUC-11 displayed a good catalytic performance for the chemical synthesis of carbonates from related epoxides and CO2 with high conversion rate. Moreover, by employing NUC-11 as a catalyst, a simulator of mustard gas, 2-chloroethyl ethyl sulfide, could be quickly and efficiently oxidized into low-toxicity products of oxidized sulfoxide (CEESO). Thus, this study offers a brand new view for the design and synthesis of functional-units-modified porous MOFs, which could be potentially applied as an excellent candidate in the growing field of efficient catalysis.
- Chen, Hongtai,Fan, Liming,Hu, Tuoping,Zhang, Xiutang
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p. 5005 - 5013
(2021/04/09)
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- A Porous Copper-Organic Framework Assembled by [Cu12] Nanocages: Highly Efficient CO2Capture and Chemical Fixation and Theoretical DFT Calculations
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A new porous copper-organic framework assembled from 12-nuclear [Cu12] nanocages {[Cu2(L4-)(H2O)2]·4DMA·2H2O}n (1) (H4L = 5,5′-(butane-1,4-diyl)-bis(oxy)-diisophthalic acid) was successfully prepared and structurally characterized. Compound 1 feathering of a 3D framework with two types of 1D nanotubular channels and a large specific surface area can effectively enrich various harmful dyes. Additionally, due to the carbon dioxide (CO2) interactions with open Cu(II) sites and the electron-rich ether oxygen atoms of ligand in 1, it exhibits a highly selective CO2 uptake. Interestingly, 1 can effectively catalyze the cycloaddition reaction of CO2 with various epoxides under mild conditions, which is ascribed to the Lewis acid Cu(II) sites in the framework of 1. Importantly, 1 acting as a heterogeneous catalyst can be recycled at least 10 times without an obvious loss of catalytic activity, and the CO2 cycloaddition mechanism was further uncovered by density functional theory (DFT) calculations. This study can greatly enrich the MOF catalysts system of CO2 conversion and also provide a valuable guidance for the design of efficient MOFs catalysts.
- Wang, Wen-Min,Wang, Wan-Ting,Wang, Mei-Ying,Gu, Ai-Ling,Hu, Tian-Ding,Zhang, Ya-Xin,Wu, Zhi-Lei
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p. 9122 - 9131
(2021/06/27)
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- Rapid continuous flow synthesis process of fluoroethylene carbonate
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The invention discloses a rapid continuous flow synthesis process of fluoroethylene carbonate, which comprises the following steps. Step I, EC vent nitrogen is added to the reaction kettle to be heated to the reaction temperature, thionyl chloride is added dropwise, and then an amount of AIBN is dropwise added, and the reaction 1.5 - 2h is carried out under 200 - 220Pa under reduced pressure. Step II. When the whole reaction of chloroethylene carbonate is completed, the reaction process is monitored by gas chromatography, and the reaction progress is monitored 1 - 3h through gas chromatography, and then the reaction process is monitored by gas chromatography, and the filtrate is filtered and the filtrate is filtered and the filtrate is 30 °C evaporated off under reduced pressure. The method avoids tedious work of repeated long-time operation in the past process, reduces labor intensity, shortens reaction time, and is suitable for continuous industrial production.
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Paragraph 0022-0027
(2021/11/10)
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- Spatially Ordered Arrangement of Multifunctional Sites at Molecule Level in a Single Catalyst for Tandem Synthesis of Cyclic Carbonates
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With fossil energy resources increasingly drying up and gradually causing serious environmental impacts, pursuing a tandem and green synthetic route for a complex and high-value-Added compound by using low-cost raw materials has attracted considerable attention. In this regard, the selective and efficient conversion of light olefins with CO2 into high-value-Added organic cyclic carbonates (OCCs) is of great significance owing to their high atom economy and absence of the isolation of intermediates. To fulfill this expectation, a multifunctional catalytic system with controllable spatial arrangement of varied catalytic sites and stable texture, in particular, within a single catalyst, is generally needed. Here, by using a stepwise electrostatic interaction strategy, imidazolium-based ILs and Au nanoparticles (NPs) were stepwise immobilized into a sulfonic group grafted MOF to construct a multifunctional single catalyst with a highly ordered arrangement of catalytic sites. The Au NPs and imidazolium cation are separately responsible for the selective epoxidation and cycloaddition reaction. The mesoporous cage within the MOF enriches the substrate molecules and provides a confined catalytic room for the tandem catalysis. More importantly, the highly ordered arrangement of the varied active sites and strong electrostatic attraction interaction result in the intimate contact and effective mass transfer between the catalytic sites, which allow for the highly efficient (>74% yield) and stable (repeatedly usage for at least 8 times) catalytic transformation. The stepwise electrostatic interaction strategy herein provides an absolutely new approach in fabricating the controllable multifunctional catalysts, especially for tandem catalysis.
- Chang, Gang-Gang,Chen, Jian,Huang, Ke-Xin,Ke, Shan-Chao,Li, Jia-Xin,Luo, Ting-Ting,Ma, Xiao-Chen,Wu, Jian,Yang, Xiao-Yu
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- High conversion of CO2 into cyclic carbonates under solvent free and ambient pressure conditions by a Fe-cyanide complex
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Methods of converting carbon dioxide into valuable chemicals are of great demand but their development is still challenging. Herein, we developed an efficient, green and facile synthetic method for the preparation of a Fe-cyanide complex. The target catalyst showed high catalytic activity for the cyclic reaction of carbon dioxide and epoxide under solvent free conditions and ambient pressure. Meanwhile, the effects of morphology of different catalysts on their catalytic activities were also investigated by the kinetic and thermodynamic studies. In addition, the catalyst could be recycled and reused for at least five successive cycles without significant decrease in the catalytic activity. This target catalyst thus represents one of the efficient and recyclable systems reported for the cyclic reaction in industry.
- Jiang, Pengbo,Ma, Lei,Wang, Kaizhi,Lan, Kai,Zhan, Zhenzhen,Iqbal, Anam,Niu, Fang,Li, Rong
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p. 17211 - 17219
(2019/11/20)
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- Straightforward synthesis of MTW-type magnesium silicalite for CO2 fixation with epoxides under mild conditions
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Aluminum-free magnesium silicalite with MTW topology (Mg-Si-ZSM-12) was fabricated via a straightforward hydrothermal synthesis route involving an initial acid co-hydrolysis step. Mg incorporation endowed superior basic properties to the MTW framework, as illustrated by CO2 sorption and temperature programmed desorption plus the activity in a typical basic reaction, Knoevenagel condensation. Mg-Si-ZSM-12 catalyzed the coupling of atmospheric CO2 with epoxides and led to the efficient production of cyclic carbonates with high yield and selectivity at relatively low temperature (down to 60 °C). The present strategy afforded a zeolitic solid base with regular 12-membered ring microporous channels that has potential application in CO2 fixation.
- Wen, Haimeng,Xie, Jingyan,Zhou, Yang,Zhou, Yu,Wang, Jun
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p. 5725 - 5735
(2019/10/23)
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- Synthesis method of vinylene carbonate
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The invention discloses a synthesis method of vinylene carbonate, which comprises the following steps: by using chlorine and ethylene carbonate as reaction raw materials and carbon tetrachloride as amedium, synthesizing monochloroethylene carbonate at 70 DEG C under the illumination of an LED blue light lamp; after the reaction is finished, evaporating out the carbon tetrachloride, and carrying out reduced pressure distillation to obtain the monochloroethylene carbonate; mixing the monochloroethylene carbonate obtained with methyl tert-butyl ether according to a certain ratio; dropwise addingtriethylamine at 55-58 DEG C under the condition of taking 2,2,6,6-tetramethyl-4-hydroxypiperidine nitroxide free radicals as a polymerization inhibitor; reacting the mixture at 60-62 DEG C after addition is finished; and after the reaction is finished, carrying out suction filtration, washing, and evaporation to obtain the triethylamine and the methyl tert-butyl ether; and carrying out reduced pressure distillation to obtain the vinylene carbonate. According to the improvement of the synthesis method, the raw materials are simple and easy to obtain, the process is simple, less waste is generated, and the total yield can reach 58% or above; the method is suitable for large-scale industrial production.
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Paragraph 0017; 0019-0022
(2019/12/02)
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- Pyridinium salt metal cobalt porphyrin as well as preparation method and application thereof
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The invention discloses pyridinium salt metal cobalt porphyrin, a preparation method thereof and an application of the pyridinium salt metal cobalt porphyrin to high-activity catalytic CO2 cycloaddition reaction. The metal cobalt porphyrin is 5,10,15,20-tetra(4-(3-(4-(N-ethyl)pyridine bromide)pyrazolyl)phenyl) cobalt (II) porphyrin, belongs to pyridinium salts and is water-soluble cation. The metal cobalt porphyrin has beneficial effects as follows: in the structure, central metal cobalt can be taken as Lewis acid, peripheral pyridinium salts can be taken as Lewis alkali, and the synergetic catalysis effect is realized; it verifies that the metal cobalt porphyrin shows excellent catalytic activity and selectivity in the cycloaddition reaction of CO2 and epoxides, TON and TOF of the metal cobalt porphyrin for catalyzing epoxy chloropropane can reach 4320 h and 529 h respectively, and selectivity exceeds 99%.
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Paragraph 0057-0066
(2019/01/17)
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- Cross-linked chitosan with a dicationic ionic liquid as a recyclable biopolymer-supported catalyst for cycloaddition of carbon dioxide with epoxides into cyclic carbonates
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Development of eco-friendly, desirable and reusable catalysts particularly for reactions in regard to carbon dioxide fixation is still attractive in academic and industrial sectors. In this study, a dicationic ionic liquid was anchored to a cheap biopolymer, i.e., chitosan and the prepared hybrid composite was used in the cycloaddition reaction of CO2 with various epoxides for preparing five-membered cyclic carbonates under solvent-free conditions in high yield and selectivity without the addition any metal co-catalyst. The catalyst was characterized by 1H and 13C NMR, FTIR, UV-vis, XPS, TG, FESEM, and BET techniques. The catalyst was recovered and recycled at least five times without losing its activity and selectivity. Moreover, it has been demonstrated that chitosan through hydrogen bonding, coordination of amine groups with CO2 and also loosely bonded bromide ion to imidazolium ion have synergistic effects on the yield and selectivity of cyclic carbonates under optimum conditions. On the basis of the obtained results, a feasible mechanism was proposed for the reaction.
- Taheri, Masoud,Ghiaci, Mehran,Shchukarev, Andrey
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p. 587 - 597
(2017/12/28)
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- Method for synthesizing carbonic ester by using carbon dioxide at ordinary pressure
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The invention discloses a method for synthesizing carbonic ester by using carbon dioxide at ordinary pressure. According to the method, the carbon dioxide is continuously introduced in a reaction system in the reaction process, constant ordinary pressure is maintained by the system, and reaction is conducted in a non-pressure resistance reactor. Lewis acid and quaternary ammonium salt are adopted by the method to form a co-catalysis system, a catalyst is cheap and easy to obtain, the operation is simple, the reaction condition is mild, and the catalytic activity is high. In an optimized reaction condition, i.e., in the ordinary pressure, reaction is conducted for 3h at 100 DEG C, the yield of cyclic carbonate is 69.5-90.2%, and the yield of diphenyl carbonate is 8.6%. The method has the advantages that the reaction can be efficiently conducted in a common non-pressure resistance reactor, the operation is safe, and the large-scale industrial production is favorably realized.
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Paragraph 0025
(2018/04/01)
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- The tubular reactor for the continuous production of vinylene carbonate
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The invention provides a method for continuously preparing vinylene carbonate by a tubular reactor. The method includes using chlorosulfuric acid and ethylene carbonate as raw materials to be synthesized into chloroethylene carbonate in the tubular reactor under the action of initiator, rectifying the chloroethylene carbonate and subjecting the rectified chloroethylene carbonate to elimination reaction with trimethylamine in the tubular reactor with existence of organic solvent and generating the vinylene carbonate. By the method for continuously preparing vinylene carbonate by the tubular reactor, existing intermittent production methods are changed, reaction speed is greatly increased, reaction period is reduced, yield is increased and productivity can be effectively improved.
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Paragraph 0028-0029
(2017/08/25)
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- Method for producing vinylene carbonate
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The invention relates to a method for producing vinylene carbonate. The method comprises the following steps: (a) performing chlorination of dried chlorine and ethylene carbonate under ultraviolet irradiation to obtain chloroethylene carbonate; (b) dissolving the chloroethylene carbonate in an organic solvent, and performing an elimination reaction with organic amine under the action of a catalyst to generate vinylene carbonate, wherein the molar ratio of the chloroethylene carbonate to organic amine is 1:(1.1-1.5), the catalyst is a mixture of copper oxide, zinc oxide and nickel protoxide in a mass ratio of (1-5):(1-5):1, and the mass is 1-5% of the mass of the chloroethylene carbonate; and (c) filtering the product obtained in the step (b), and performing reduced-pressure refining. By adopting a specific catalyst, the chloroethylene carbonate reacts with organic amine, the reaction temperature can be lowered, the polymerization of the generated vinylene carbonate is avoided, and thus the yield and purity are improved.
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Paragraph 0017
(2017/07/21)
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- Method for preparing high-purity vinylene carbonate
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The present invention relates to a method for preparing high-purity vinylene carbonate. The method comprises the steps of (a) carrying out a chlorination reaction between ethylene carbonate and dry chlorine under the irradiation of ultraviolet light to produce chloroethylene carbonate; (b) dispersing chloroethylene carbonate into methylsilicone oil, then, adding an organic amine, and carrying out an elimination reaction to obtain vinylene carbonate, wherein the mole ratio of chloroethylene carbonate to the organic amine is 1: (1.1-1.5); and (c) refining the products obtained in the step (b) under reduced pressure. Through carrying out the elimination reaction between chloroethylene carbonate and the organic amine in the methylsilicone oil, and controlling the ratio of chloroethylene carbonate to the organic amine, the extent of the reaction can be improved, and the separation of each product can be facilitated, so as to increase the product purity.
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Paragraph 0018
(2017/08/29)
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- Cycloaddition of CO2 and epoxide catalyzed by amino- and hydroxyl-rich graphitic carbon nitride
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Graphitic carbon nitride (g-C3N4) shows great application potential in the activation of CO2 due to its basic surface functionalities and highly specific electronic properties. Herein, to improve its catalytic performance, g-C3N4 was activated by protonation using H2SO4. The texture, surface chemistry and electronic properties of the as-prepared g-C3N4 were then studied. The synthesis of cyclic carbonate from the cycloaddition of CO2 and epoxide was selected as a model reaction to investigate the catalytic performance. The protonated g-C3N4 exhibited a much higher catalytic activity than the pristine g-C3N4. The generation of terminal amino and hydroxyl groups due to the hydrolysis of g-C3N4 under acidic conditions as well as the higher specific surface area are responsible for the enhanced catalytic performance.
- Huang, Zhijun,Li, Fengbo,Chen, Bingfeng,Yuan, Guoqing
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p. 2942 - 2948
(2016/05/24)
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- Method for preparing monochloroethylene carbonate
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The invention relates to a method for preparing monochloroethylene carbonate. The method comprises the steps: arranging a filler layer in a tower reactor along a tower height direction at intervals of 1 meter, mounting a bracket in the tower reactor along the tower height direction at intervals of 1 meter, mounting a first mercury immersion lamp at the bottom of each bracket, and separately mounting a liquid uniform distributor and a second mercury immersion lamp above each filler layer; preheating ethylene carbonate to the temperature of 60 DEG C, then, adding an initiator and a catalyst into the preheated ethylene carbonate, and heating the mixture to the temperature of 60 DEG C, so as to obtain ethylene carbonate liquid containing the initiator and the catalyst; introducing nitrogen gas from the bottom of a tower so as to replace air in the tower, and venting nitrogen gas exhaust gas; drying and dehydrating chlorine gas, then, heating the chlorine gas to the temperature of 65 DEG C, separately introducing chlorine gas to the bottom and middle part of the tower, adding the ethylene carbonate liquid containing the initiator and the catalyst from the top of the tower, carrying out gas-liquid counterflow contact reaction, collecting tower bottom liquid, i.e. chloroethylene carbonate, and treating tower top exhaust gas, thereby obtaining hydrochloric acid and chlorinated paraffin.
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Paragraph 0039-0043
(2017/06/20)
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- Vinylene carbonate preparation method
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The invention provides a vinylene carbonate preparation method. The method mainly comprises the following steps: 1, synthesizing chlorovinylene carbonate by adopting ethylene carbonate as a precursor and sulfuric chloride as a chloridizing agent; 2, carrying out a dechlorination reaction on the chlorovinylene carbonate synthesized in step 1 by adopting ammonia gas as a dechlorination agent to generate crude vinylene carbonate; and 3, distilling the crude vinylene carbonate, and rectifying to obtain pure vinylene carbonate. Reaction process parameters are adjusted to improve the chlorination yield, and an antioxidant and a polymerization inhibitor are properly used to short the dechlorination reaction time without influencing the reaction yield.
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Paragraph 0023
(2016/12/22)
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- Functionalized dicyandiamide-formaldehyde polymers as efficient heterogeneous catalysts for conversion of CO2 into organic carbonates
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The application of the dicyandiamide-formaldehyde polymer (DFP), which is a kind of organic polymer flocculant, as a supporter for conversion of CO 2 into organic carbonates was studied in this work, and four kinds of dicyandiamide-formaldehyde polymers were synthesized and employed as efficient single component, metal-free, multifunctional, polyquaternium catalysts for cycloaddition of CO2 with epoxides. The results indicated that the ammonium bromide modified dicyandiamide-formaldehyde polymer (ABMDFP) was the optimal catalyst among the four polymers and was observed to be suitable for various substrates. A possible mechanism of ring-opening of epoxides assisted by the hydroxyl and activation of CO2 induced by amines was proposed. In addition, the catalyst could be easily recovered and reused six times with only a slight loss of catalytic activity. Furthermore, the catalyst exhibited good activity in the synthesis of dimethyl carbonate (DMC) through a transesterification reaction. The functional organic polymers in this study were proved to be efficient heterogeneous catalysts for the cycloaddition reaction of CO2, which was applicable to the development of fixed-bed continuous flow reactors. the Partner Organisations 2014.
- Meng, Xiang-Lei,Nie, Yi,Sun, Jian,Cheng, Wei-Guo,Wang, Jin-Quan,He, Hong-Yan,Zhang, Suo-Jiang
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p. 2771 - 2778
(2014/05/06)
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- Terminal aziridines by addition of Grignard reagents or organoceriums to an (α-chloro)sulfinylimine
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Reaction of N-(2-chloroethylidene)-tert-butylsulfinamide with Grignard reagents or organoceriums gives terminal N-tert-butylsulfinyl aziridines in good yields and (mainly with organoceriums) good diastereomeric ratios. Oxidation of terminal N-tert-butylsu
- Hodgson, David M.,Kloesges, Johannes,Evans, Brian
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experimental part
p. 1923 - 1932
(2010/01/19)
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- Non-aqueous electrolyte and lithium secondary battery using the same
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A non-aqueous electrolyte comprising a non-aqueous solvent and a lithium salt dissolved therein, and a cyclic carbonate, linear carbonate, and vinylene carbonate having a chlorine content of 100 ppm or less, and a lithium secondary battery using the same.
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Page column 6
(2008/06/13)
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- Model Studies of Coenzyme B12 Dependent Diol Dehydratase. 1. Synthetic, Physical Property, and Product Studies of Two Key, Cobalt-Bound, Putative Diol Dehydratase Intermediates
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Following a brief introduction to the controversial question of cobalt participation or nonparticipation in the adenosylcobalamin (coenzyme B12) dependent diol dehydratase rearrangement reaction, HOCH2CH2OH -> CH3CHO + H2O, the two key, cobalt-bound, putative diol dehydratase intermediates, Co-CH(OH)CH2OH (1) and Co-CH2CHO (2), are prepared and studied by using the coenzyme B12, Schiff base, model system, RCoX.The first synthesis, in 80percent yield, and isolation of the often postulated, but unproven, intermediate 1 are reported in a carbonate-protected form, , compound 3, (3).Following the full characterization of 3 by 360-MHz 1H NMR, IR, and X-ray crystallography, including its unexpectedly complex solution NMR behavior and the axial 1,5,6-trimethylbenzimidazole binding constant, the MeO--catalyzed deproptection in MeOH of 3 is described.The resultant rearrangement reaction and complete stoichiometry to 1 equiv of CoIICl, 0.5 equiv of CH3OCO2CH3 and CH3OCO2-, and 95 +/- 4percent CH3CHO are reported.The observed stoichiometry and mass and charge balance suggest that a *CH2CHO intermediate is formed, and evidence is presented suggesting that the CH3OH solvent is the H* source, *CH2CHO + CH3OH -> CH3CHO + *CH2OH.Following the examination of several unsuccessful routes, the intermediate expected from cobalt-participation pathways, Co-CH2CHO, was prepared, OHCCH2CoI (7), and found to be reasonably stable as previously observed for all the other known formylmethyl complexes, and, therefore, apparently not an intermediate in the MeO--catalyzed deprotection and rearrangement reaction of 3.The results of attempts to use seven protecting groups other than carbonate and the relative advantages and disadvantages of carbonate-protected 3 are then summarized and discussed.In the following paper, 1b a kinetic and mechanistic study of the rearrangement reaction is presented.
- Finke, Richard G.,McKenna, William P.,Schiraldi, David A.,Smith, Brad L.,Pierpont, Cortlandt
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p. 7592 - 7604
(2007/10/02)
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