- Selective electrochemical deprotection of cinnamyl ethers, esters, and carbamates
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Electrochemical deprotection of the cinnamyl moiety from ethers, esters, and carbamates was studied with the focus on O- versus N- selectivity as well as selectivity over allyl or benzyl systems.
- Hansen, Jeff,Freeman, Stanley,Hudlicky, Tomas
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- EXAMINATION OF HIGH-LOADED NICKEL CATALYSTS BY IR SPECTROSCOPY: EFFECT OF THE SUPPORT AND Pd ON SURFACE PROPERTIES
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Activation of the ammonia molecule and subsequent adsorption of the NH2 fragment on the surface of the NiO + Pd/TiO2 catalysts, in contrast to NiO + PdSiO2 catalysts, was demonstrated by IR spectroscopy.The decrease in the NiO + Pd/TiO2 catalyst acidity was manifested in the higher catalyst stability in reductive amination of diethylene glycol to morpholine.
- Jiratova, Kveta,Moravkova, Lenka,Snajdaufova, Hana,Paukshtis, Evgenii A.
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- Manganese-Catalyzed Sequential Hydrogenation of CO2 to Methanol via Formamide
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Mn(I)-PNP pincer catalyzed sequential one-pot homogeneous CO2 hydrogenation to CH3OH by molecular H2 is demonstrated. The hydrogenation consists of two parts - N-formylation of an amine utilizing CO2 and H2, and subsequent formamide reduction to CH3OH, regenerating the amine in the process. A reported air-stable and well-defined Mn-PNP pincer complex was found active for the catalysis of both steps. CH3OH yields up to 84% and 71% (w.r.t amine) were obtained, when benzylamine and morpholine were used as amines, respectively; and a TON of up to 36 was observed. In our opinion, this study represents an important development in the nascent field of base-metal-catalyzed homogeneous CO2 hydrogenation to CH3OH.
- Kar, Sayan,Goeppert, Alain,Kothandaraman, Jotheeswari,Prakash, G. K. Surya
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- Experimental investigations of thermal stability of some morpholinecarbamic acid complexes of copper(II) and zinc(II)
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Some new carbamates, viz. M(MorphcbmH)2X2 (MorphcbmH?=?morpholinecarbamic acid, M?=?Cu, X?=?Cl, ClO4,NO3; M?=?Zn, X?=?Cl, ClO4, NO3, CH3COO and X2?=?SO4), h
- Kalia, Shashi B.,Kumar, Rajesh,Bharti, Monika,Christopher
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- On-resin N-terminal peptoid degradation: Toward mild sequencing conditions
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A novel approach to sequentially degrade peptoid N-terminal N-(substituted)glycine residues on the solid-phase using very mild conditions is reported. This method relies on the treatment of resin-bound, bromoacetylated peptoids with silver perchlorate in THF, leading to an intramolecular cyclization reaction to liberate the terminal residue as a N-substituted morpholine-2,5-dione, resulting in a truncated peptoid upon hydrolysis and a silver bromide byproduct. Side-chain functional group tolerance is explored and reaction kinetics are determined. In a series of pentapeptoids possessing variable, non-nucleophilic side-chains at the second position (R2), we demonstrate that sequential N-terminal degradation of the first two residues proceeds in 87% and 74% conversions on average, respectively. We further demonstrate that the degradation reaction is selective for peptoids, and represents substantial progress toward a mild, iterative sequencing method for peptoid oligomers.
- Proulx, Caroline,No?, Falko,Yoo, Stan,Connolly, Michael D.,Zuckermann, Ronald N.
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- Kinetics and mechanism of large rate enhancement in an acidic aqueous cleavage of the tertiary amide bond of N-(2-methoxyphenyl)-N′-morpholinophthalamide (1)
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The rate of conversion of 1 to N-(2-methoxyphenyl)phthalimide (2) within [HCl] range 5.0 × 10-3-1.0 M at 1.0 M ionic strength (by NaCl) reveals the presence of both uncatalyzed and specific acid-catalyzed kinetic terms in the rate law. Intramolecular carboxamide group-assisted cleavage of amide bond of 1 reveals rate enhancement of much larger than 106-fold compared to the expected rate of analogous intermolecular reaction.
- Sim, Yoke-Leng,Ariffin, Azhar,Khan, M. Niyaz
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- New Allyl Group Acceptors for Palladium Catalyzed Removal of Allylic Protections and Transacylation of Allyl Carbamates.
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Key words: allylic protecting groups, palladium catalysis, transacylation, phenyltrihydrosilane, N-methyl-N-(trimethylsilyl)trifluoroacetamide.Allyl carboxylates, carbamates and phenoxides may be cleaved or transacylated in the presence of palladium catalyst and either phenyltrihydridosilane or N-methyl-N-(trimethylsilyl)trifluoroacetamide.These reactions are totally compatible with the presence of Boc and, as far as phenyltrihydrosilane is concerned, Fmoc protections.
- Dessolin, Michele,Guillerez, Marie-George,Thieriet, Nathalie,Guibe, Francois,Loffet, Albert
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- Infrared studies of amine, pyridine, and phosphine derivatives of tungsten hexacarbonyl
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Seventeen complexes, LW(CO)5, where L = amine, pyridine, or phosphine, have been prepared and examined in the C-O stretching region of their infrared spectra. The C-O stretching frequencies and force constants in the amine, pyridine, and phosphine series decrease as the basicity of L increases, and the magnitude of this decrease is virtually the same for all three groups of ligands. The results suggest that W-L π bonding, even for the phosphines, need not be invoked to explain the C-O stretching frequency shifts in these metal carbonyl complexes.
- Angelici, Robert J.,Malone, Mary Diana
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- Thermodynamics and equilibrium solubility of carbon dioxide in diglycolamine/morpholine/water
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Carbon dioxide solubility was studied in 3.5 m (23.5 wt %) morpholine (MOR), 17.7 m (65 wt %) 2-aminoethoxyethanol (diglycolamine or DGA), and 3.6 m MOR + 14.7 m DCA (11 wt % MOR + 53 wt % DGA). CO2 solubility was determined by dynamic measurements with a wetted wall contactor. Carbamate and bicarbonate concentrations were determined by 13C NMR in solutions loaded with 13CO2. The data are represented by the electrolyte NRTL model. At a given CO2 loading (mol/mol amine), the CO2 vapor pressure over 3.5 m MOR is 10 to 1000 times greater than 17.7 m DGA. In 3.6 m MOR + 14.7 m DGA, the CO2 vapor pressure is 5 to 7 times greater than in 17.7 m DGA at high CO2 loading, but the same below 0.2 loading. MOR carbamate is less stable than DGA carbamate by a factor of 7 to 10 from (300 to 333) K. The model predicts that MOR vapor pressure is 100 times greater than DGA over 3.6 m MOR + 14.7 m DGA from (313 to 333) K. The heat of CO2 absorption in the blend is equivalent to 17.7 m DGA up to 0.35 loading but is 40 % lower at 0.5 loading. The working capacity of the blend is 17 % less than 17.7 m DGA.
- Al-Juaied, Mohammed,Rochelle, Gary T.
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- The pyridoxamine action on Amadori compounds: A reexamination of its scavenging capacity and chelating effect
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Amadori compounds act as precursors in the formation of advanced glycation end products (AGEs) by non-enzymatic protein glycation, which are involved in ensuing protein damage. Pyridoxamine is a potent drug against protein glycation, and can act on several pathways in the glycation process. Nevertheless, the pyridoxamine inhibition action on Amadori compounds oxidation is still unclear. In this work, we have studied the Schiff base formation between pyridoxamine and various Amadori models at pH 7.4 at 37 °C in the presence of NaCNBH3. We detected an adduct formation, which suggests that pyridoxamine reacts with the carbonyl group in Amadori compounds. The significance of this mechanism is tested by comparison of the obtained kinetics rate constants with that obtained for 4-(aminomethyl)-pyridine, a structural analogue of pyridoxamine without post-Amadori action. We also study the chelating effect of pyridoxamine on metal ions. We have determined the complexation equilibrium constants between pyridoxamine, N-(1-deoxy-d-fructos-1-yl)-l-tryptophan, aminoguanidine, and ascorbic acid in the presence of Zn2+. The results show that the strong stability of pyridoxamine complexes is the key in its post-Amadori inhibition action. On the other hand results explain the lack of inhibition of aminoguanidine (a glycation inhibitor) in the post-Amadori reactions.
- Adrover, Miquel,Vilanova, Bartolome,Frau, Juan,Munoz, Francisco,Donoso, Josefa
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- REDUCTIVE AMINATION OF DIETHYLENE GLYCOL TO MORPHOLINE OVER SUPPORTED NICKEL CATALYSTS: ZEOLITES AS CATALYST ADMIXTURES
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The effect of HZSM-5, H-silicalite and amorphous silica admixtures on the surface properties of nickel catalysts as well as on their activities, selectivities and stabilities in the reductive amination of diethylene glycol was studied.It was found that, in comparison with amorphous silica, zeolites do not positively affect the catalytic properties of nickel catalysts.In addition, the acidity of the zeolites, the dispersity of the nickel phase, changes in the chemical composition during the reaction and adsorption of the reaction components or intermediates on the surface and consequent blocking of the zeolite surface played a role.
- Jiratova, Kveta,Snajdaufova, Hana,Moravkova, Lenka,Kubelkova, Ludmila
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- The benzyl can be selectively removed by visible light or near visible light. Method for protecting allyl and propargyl group
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The invention provides a method for selectively removing benzyl, allyl and propargyl protecting groups by visible light or near visible light, namely a substrate containing benzyl, allyl or propargyl protecting groups. The method has the advantages of simple operation, safe and clean visible light or near visible light as excitation conditions, cheap and easily available reagents, high reaction yield, high reaction chemistry and regional selectivity, and is suitable for selective removal of benzyl, allyl and propargyl protecting groups in various substrates.
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Paragraph 0024
(2021/10/16)
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- A Lewis Base Nucleofugality Parameter, NFB, and Its Application in an Analysis of MIDA-Boronate Hydrolysis Kinetics
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The kinetics of quinuclidine displacement of BH3 from a wide range of Lewis base borane adducts have been measured. Parameterization of these rates has enabled the development of a nucleofugality scale (NFB), shown to quantify and predict the leaving group ability of a range of other Lewis bases. Additivity observed across a number of series R′3-nRnX (X = P, N; R′ = aryl, alkyl) has allowed the formulation of related substituent parameters (nfPB, nfAB), providing a means of calculating NFB values for a range of Lewis bases that extends far beyond those experimentally derived. The utility of the nucleofugality parameter is explored by the correlation of the substituent parameter nfPB with the hydrolyses rates of a series of alkyl and aryl MIDA boronates under neutral conditions. This has allowed the identification of MIDA boronates with heteroatoms proximal to the reacting center, showing unusual kinetic lability or stability to hydrolysis.
- García-Domínguez, Andrés,Gonzalez, Jorge A.,Leach, Andrew G.,Lloyd-Jones, Guy C.,Nichol, Gary S.,Taylor, Nicholas P.
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supporting information
(2022/01/04)
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- Rational selection of co-catalysts for the deaminative hydrogenation of amides
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The catalytic hydrogenation of amides is an atom economical method to synthesize amines. Previously, it was serendipitously discovered that the combination of a secondary amide co-catalyst with (iPrPNP)Fe(H)(CO) (iPrPNP = N[CH2CH2(PiPr2)]2-), results in a highly active base metal system for deaminative amide hydrogenation. Here, we use DFT to develop an improved co-catalyst for amide hydrogenation. Initially, we computationally evaluated the ability of a series of co-catalysts to accelerate the turnover-limiting proton transfer during C-N bond cleavage and poison the (iPrPNP)Fe(H)(CO) catalyst through a side reaction. TBD (triazabicyclodecene) was identified as the leading co-catalyst. It was experimentally confirmed that when TBD is combined with (iPrPNP)Fe(H)(CO) a remarkably active system for amide hydrogenation is generated. TBD also enhances the activity of other catalysts for amide hydrogenation and our results provide guidelines for the rational design of future co-catalysts.
- Artús Suàrez, Lluís,Jayarathne, Upul,Balcells, David,Bernskoetter, Wesley H.,Hazari, Nilay,Jaraiz, Martín,Nova, Ainara
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p. 2225 - 2230
(2020/03/10)
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- Selective Room-Temperature Hydrogenation of Amides to Amines and Alcohols Catalyzed by a Ruthenium Pincer Complex and Mechanistic Insight
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We report a room-temperature protocol for the hydrogenation of various amides to produce amines and alcohols. Compared with most previous reports for this transformation, which use high temperatures (typically, 100-200 °C) and H2 pressures (10-100 bar), this system proceeds under extremely mild conditions (RT, 5-10 bar of H2). The hydrogenation is catalyzed by well-defined ruthenium-PNNH pincer complexes (0.5 mol %) with potential dual modes of metal-ligand cooperation. An unusual Ru-amidate complex was formed and crystallographically characterized. Mechanistic investigations indicate that the room-temperature hydrogenation proceeds predominantly via the Ru-N amido/amine metal-ligand cooperation.
- Ben-David, Yehoshoa,Kar, Sayan,Kumar, Amit,Leitus, Gregory,Milstein, David,Rauch, Michael
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p. 5511 - 5515
(2020/07/21)
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- Platinum-Triggered Bond-Cleavage of Pentynoyl Amide and N-Propargyl Handles for Drug-Activation
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The ability to create ways to control drug activation at specific tissues while sparing healthy tissues remains a major challenge. The administration of exogenous target-specific triggers offers the potential for traceless release of active drugs on tumor sites from antibody-drug conjugates (ADCs) and caged prodrugs. We have developed a metal-mediated bond-cleavage reaction that uses platinum complexes [K2PtCl4 or Cisplatin (CisPt)] for drug activation. Key to the success of the reaction is a water-promoted activation process that triggers the reactivity of the platinum complexes. Under these conditions, the decaging of pentynoyl tertiary amides and N-propargyls occurs rapidly in aqueous systems. In cells, the protected analogues of cytotoxic drugs 5-fluorouracil (5-FU) and monomethyl auristatin E (MMAE) are partially activated by nontoxic amounts of platinum salts. Additionally, a noninternalizing ADC built with a pentynoyl traceless linker that features a tertiary amide protected MMAE was also decaged in the presence of platinum salts for extracellular drug release in cancer cells. Finally, CisPt-mediated prodrug activation of a propargyl derivative of 5-FU was shown in a colorectal zebrafish xenograft model that led to significant reductions in tumor size. Overall, our results reveal a new metal-based cleavable reaction that expands the application of platinum complexes beyond those in catalysis and cancer therapy.
- Oliveira, Bruno L.,Stenton, Benjamin J.,Unnikrishnan,De Almeida, Cátia Rebelo,Conde, Jo?o,Negr?o, Magda,Schneider, Felipe S.S.,Cordeiro, Carlos,Ferreira, Miguel Godinho,Caramori, Giovanni F.,Domingos, Josiel B.,Fior, Rita,Bernardes, Gon?alo J. L.
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supporting information
p. 10869 - 10880
(2020/07/04)
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- Practical Synthesis of Phosphinic Amides/Phosphoramidates through Catalytic Oxidative Coupling of Amines and P(O)?H Compounds
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Herein, we report a highly efficient ZnI2-triggered oxidative cross-coupling reaction of P(O)?H compounds and amines. This operationally simple protocol provides unprecedented generic access to phosphinic amides/phosphoramidate derivatives in good yields and short reaction time. Besides, the reaction proceeds under mild conditions, which avoids the use of hazardous reagents, and is applicable to scale-up syntheses as well as late-stage functionalization of drug molecules. The stereospecific coupling is also achieved from readily available optically enriched P(O)?H compounds.
- Tan, Chen,Liu, Xinyuan,Jia, Huanxin,Zhao, Xiaowen,Chen, Jian,Wang, Zhiyong,Tan, Jiajing
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p. 881 - 887
(2020/01/02)
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- Catalytic Hydrogenation of Thioesters, Thiocarbamates, and Thioamides
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Direct hydrogenation of thioesters with H2 provides a facile and waste-free method to access alcohols and thiols. However, no report of this reaction is documented, possibly because of the incompatibility of the generated thiol with typical hydrogenation catalysts. Here, we report an efficient and selective hydrogenation of thioesters. The reaction is catalyzed by an acridine-based ruthenium complex without additives. Various thioesters were fully hydrogenated to the corresponding alcohols and thiols with excellent tolerance for amide, ester, and carboxylic acid groups. Thiocarbamates and thioamides also undergo hydrogenation under similar conditions, substantially extending the application of hydrogenation of organosulfur compounds.
- Luo, Jie,Rauch, Michael,Avram, Liat,Ben-David, Yehoshoa,Milstein, David
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supporting information
p. 21628 - 21633
(2021/01/11)
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- Discovery and characterization of an acridine radical photoreductant
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Photoinduced electron transfer (PET) is a phenomenon whereby the absorption of light by a chemical species provides an energetic driving force for an electron-transfer reaction1–4. This mechanism is relevant in many areas of chemistry, including the study of natural and artificial photosynthesis, photovoltaics and photosensitive materials. In recent years, research in the area of photoredox catalysis has enabled the use of PET for the catalytic generation of both neutral and charged organic free-radical species. These technologies have enabled previously inaccessible chemical transformations and have been widely used in both academic and industrial settings. Such reactions are often catalysed by visible-light-absorbing organic molecules or transition-metal complexes of ruthenium, iridium, chromium or copper5,6. Although various closed-shell organic molecules have been shown to behave as competent electron-transfer catalysts in photoredox reactions, there are only limited reports of PET reactions involving neutral organic radicals as excited-state donors or acceptors. This is unsurprising because the lifetimes of doublet excited states of neutral organic radicals are typically several orders of magnitude shorter than the singlet lifetimes of known transition-metal photoredox catalysts7–11. Here we document the discovery, characterization and reactivity of a neutral acridine radical with a maximum excited-state oxidation potential of ?3.36 volts versus a saturated calomel electrode, which is similarly reducing to elemental lithium, making this radical one of the most potent chemical reductants reported12. Spectroscopic, computational and chemical studies indicate that the formation of a twisted intramolecular charge-transfer species enables the population of higher-energy doublet excited states, leading to the observed potent photoreducing behaviour. We demonstrate that this catalytically generated PET catalyst facilitates several chemical reactions that typically require alkali metal reductants and can be used in other organic transformations that require dissolving metal reductants.
- MacKenzie, Ian A.,Wang, Leifeng,Onuska, Nicholas P. R.,Williams, Olivia F.,Begam, Khadiza,Moran, Andrew M.,Dunietz, Barry D.,Nicewicz, David A.
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- Palladium doping of In2O3 towards a general and selective catalytic hydrogenation of amides to amines and alcohols
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Herein, the first general heterogeneous catalytic protocol for the hydrogenation of primary, secondary and tertiary amides to their corresponding amines and alcohols is described. Advantageously, this catalytic protocol works under additive-free conditions and is compatible with the presence of aromatic rings, which are fully retained in the final products. This hydrogenative C-N bond cleavage methodology is catalyzed by a Pd-doped In2O3 catalyst prepared by a microwave hydrothermal-assisted method followed by calcination. This catalyst displays highly dispersed Pd2+ ionic species in the oxide matrix of In2O3 that have appeared to be essential for its high catalytic performance.
- Sorribes, Iván,Lemos, Samantha C. S.,Martín, Santiago,Mayoral, Alvaro,Lima, Renata C.,Andrés, Juan
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p. 6965 - 6976
(2019/12/26)
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- Sodium Triethylborohydride-Catalyzed Controlled Reduction of Unactivated Amides to Secondary or Tertiary Amines
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The first transition-metal-free catalytic protocol for controlled reduction of amide functions using cheap and bench-stable hydrosilanes as reducing agents has been established. By altering the hydrosilane and solvent, the new method enables the selective cleavage of unactivated C-O bonds in amides and allows the C-N bonds to selectively break via the deacylated cleavage. Overall, this novel process may offer a versatile alternative to current methodologies employing stoichiometric metal systems for the controlled reduction of carboxamides.
- Yao, Wubing,He, Lili,Han, Deman,Zhong, Aiguo
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p. 14627 - 14635
(2019/12/02)
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- Sodium Triethylborohydride-Catalyzed Controlled Reduction of Unactivated Amides to Secondary or Tertiary Amines
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The first transition-metal-free catalytic protocol for controlled reduction of amide functions using cheap and bench-stable hydrosilanes as reducing agents has been established. By altering the hydrosilane and solvent, the new method enables the selective cleavage of unactivated C-O bonds in amides and allows the C-N bonds to selectively break via the deacylated cleavage. Overall, this novel process may offer a versatile alternative to current methodologies employing stoichiometric metal systems for the controlled reduction of carboxamides.
- Yao, Wubing,He, Lili,Han, Deman,Zhong, Aiguo
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- Nickel-Catalyzed Amide Bond Formation from Methyl Esters
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Despite being one of the most important and frequently run chemical reactions, the synthesis of amide bonds is accomplished primarily by wasteful methods that proceed by stoichiometric activation of one of the starting materials. We report a nickel-catalyzed procedure that can enable diverse amides to be synthesized from abundant methyl ester starting materials, producing only volatile alcohol as a stoichiometric waste product. In contrast to acid- and base-mediated amidations, the reaction is proposed to proceed by a neutral cross coupling-type mechanism, opening up new opportunities for direct, efficient, chemoselective synthesis.
- Ben Halima, Taoufik,Masson-Makdissi, Jeanne,Newman, Stephen G.
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supporting information
p. 12925 - 12929
(2018/09/14)
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- Sustainable hydrogenation of aliphatic acyclic primary amides to primary amines with recyclable heterogeneous ruthenium-tungsten catalysts
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The hydrogenation of amides is a straightforward method to produce (possibly bio-based) amines. However current amide hydrogenation catalysts have only been validated in a rather limited range of toxic solvents and the hydrogenation of aliphatic (acyclic) primary amides has rarely been investigated. Here, we report the use of a new and relatively cheap ruthenium-tungsten bimetallic catalyst in the green and benign solvent cyclopentyl methyl ether (CPME). Besides the effect of the Lewis acid promotor, NH3 partial pressure is identified as the key parameter leading to high primary amine yields. In our model reaction with hexanamide, yields of up to 83% hexylamine could be achieved. Beside the NH3 partial pressure, we investigated the effect of the catalyst support, PGM-Lewis acid ratio, H2 pressure, temperature, solvent tolerance and product stability. Finally, the catalyst was characterized and proven to be very stable and highly suitable for the hydrogenation of a broad range of amides.
- Coeck, Robin,Berden, Sarah,De Vos, Dirk E.
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supporting information
p. 5326 - 5335
(2019/10/11)
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- An Efficient Ruthenium Catalyst Bearing Tetradentate Ligand for Hydrogenations of Carbon Dioxide
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A ruthenium complex with a tetradentate bipyridine ligand was proved to be a highly efficient catalyst for the conversions of CO2. Turnover numbers up to 300 000, 9800, and 2100 were achieved for the hydrogenations of CO2 to formamides, formamides to methanol and amines, and the direct hydrogenation of CO2 to methanol, respectively.
- Zhang, Feng-Hua,Liu, Chong,Li, Wei,Tian, Gui-Long,Xie, Jian-Hua,Zhou, Qi-Lin
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supporting information
p. 1000 - 1002
(2018/09/21)
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- An Additive-Free, Base-Catalyzed Protodesilylation of Organosilanes
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We report an additive-free, base-catalyzed C-, N-, O-, and S-Si bond cleavage of various organosilanes in mild conditions. The novel catalyst system exhibits high efficiency and good functional group compatibility, providing the corresponding products in good to excellent yields with low catalyst loadings. Overall, this transition-metal-free process may offer a convenient and general alternative to current employing excess bases, strong acids, or metal-catalyzed systems for the protodesilylation of organosilanes.
- Yao, Wubing,Li, Rongrong,Jiang, Huajiang,Han, Deman
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p. 2250 - 2255
(2018/02/23)
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- Ethanol-mediated N-formylation of amines with CO2/H2 over cobalt catalysts
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The CO2-involved synthesis of chemicals is of great significance from a green and sustainable point of view. Herein, we present an efficient Co-based catalytic system composed of a commercially available Co salt, the tetradentate phosphine ligand P-(CH2CH2PPh2)3, and a base, denoted as [Co]/PP3/base, for the synthesis of formamides via the formylation of amines with CO2/H2. It was indicated that the selectivity of products (i.e., formamide or methylamine) could be tuned to some extent via changing the solvent and the base. Using ethanol as the solvent, the Co(ClO4)2·6H2O/PP3/K2CO3 system showed high activity for the production of formamides, affording product yields of 82-95%, together with its broad substrate scope. Exploration of the reaction mechanism indicated that formamide was formed with HCOOH as the intermediate, while the methylamine byproduct was produced with HCHO as the intermediate via the hydrogenolysis of dialkylaminomethane.
- Liu, Zhenghui,Yang, Zhenzhen,Ke, Zhengang,Yu, Xiaoxiao,Zhang, Hongye,Yu, Bo,Zhao, Yanfei,Liu, Zhimin
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p. 13933 - 13937
(2018/08/21)
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- Selective Iron-Catalyzed Deaminative Hydrogenation of Amides
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The five-coordinate iron(II) hydride complex (iPrPNP)Fe(H)CO (iPrPNP = N[CH2CH2(PiPr2)]2) was found to selectively catalyze deaminative hydrogenation of amides to the corresponding amines and primary alcohols. It is one of the most active amide hydrogenation catalysts reported to date, with turnover numbers (TONs) in excess of 1000 observed for multiple substrates and TONs greater than 4000 obtained for activated formanilides. The amide C-N cleavage reactions occur with a preference for electron-withdrawing substituents and with greater activity for formamides compared with acetamides and benzamides. Stoichiometric reactions between (iPrPNP)Fe(H)CO and formanilide afforded the new iron(II) complex (iPrPNHP)Fe(H)CO(N(Ph)HCO) resulting from N-H addition across the Fe-N bond. Complexes of this type were identified as the resting state during catalytic hydrogenation reactions containing secondary amides. Addition of a Lewis acid cocatalyst provided further enhancement of the productivity of catalytic amide hydrogenations.
- Jayarathne, Upul,Zhang, Yuanyuan,Hazari, Nilay,Bernskoetter, Wesley H.
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p. 409 - 416
(2017/04/26)
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- Direct Catalytic Hydrogenation of Simple Amides: A Highly Efficient Approach from Amides to Amines and Alcohols
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A highly chemoselective and reactive direct catalytic reduction of various amides to amines and alcohols was developed by using a tetradentate ruthenium complex. The catalytic system showed excellent activity (turnover numbers up to 19 600) and great functional group tolerance under mild reaction conditions, compared to several bidentate and tridentate ruthenium-catalyzed systems.
- Shi, Liyang,Tan, Xuefeng,Long, Jiao,Xiong, Xiong,Yang, Song,Xue, Peng,Lv, Hui,Zhang, Xumu
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supporting information
p. 546 - 548
(2017/01/18)
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- O -Phthalaldehyde catalyzed hydrolysis of organophosphinic amides and other P(O)-NH containing compounds
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Over 50 years ago, Jencks and Gilchrist showed that formaldehyde catalyses the hydrolysis of phosphoramidate through electrophilic activation, induced by covalent attachment to its nitrogen atom. Given our interest in the use of aldehydes as catalysts, this work was revisited to identify a superior catalyst, o-phthalaldehyde, which facilitates hydrolyses of various organophosphorus compounds bearing P(O)-NH subunits under mild conditions. Interestingly, chemoselective hydrolysis of the P(O)-N bonds could be accomplished in the presence of P(O)-OR bonds.
- Li, Bin-Jie,Simard, Ryan D.,Beauchemin, André M.
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supporting information
p. 8667 - 8670
(2017/08/10)
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- Simple and efficient Fmoc removal in ionic liquid
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A mild method for an efficient removal of the fluorenylmethoxycarbonyl (Fmoc) group in ionic liquid was developed. The combination of a weak base such as triethylamine and [Bmim][BF4] makes the entire system more efficient for the cleavage at room temperature of various amines and amino acid methyl esters in short reaction times. The procedure works well even in the case of N-Fmoc amino acids bearing acid-sensitive protecting groups and of N-alkylated amino acid methyl esters. The solvent-free condition provides a complementary method for Fmoc deprotection in solution phase peptide synthesis and modern organic synthesis.
- Di Gioia,Costanzo,De Nino,Maiuolo,Nardi,Olivito,Procopio
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p. 36482 - 36491
(2017/08/02)
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- Colloid and nanosized catalysts in organic synthesis: XII. Hydrogenation of carbonitriles catalyzed by nickel nanoparticles
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Hydrogenation of carbonitriles catalyzed by nickel nanoparticles in isopropanol proceeds under atmospheric pressure of hydrogen within 6-15 h to yield mainly secondary amines. Hydrogenation of α-aminonitriles results in reductive decyanation. β-Aminonitriles undergo hydrogenolysis at the nitrogen-carbon bond.
- Mokhov,Popov,Shcherbakova
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p. 273 - 280
(2016/04/20)
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- Putrescine Transaminases for the Synthesis of Saturated Nitrogen Heterocycles from Polyamines
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Putrescine transaminase (pATA; EC 2.6.1.82) catalyzes the transfer of an amino group from terminal diamine donor molecules to keto acid acceptors by using pyridoxal-5′-phosphate as a cofactor. The ygjG genes from Escherichia coli K12, Bacillus megaterium, and Bacillus mycoides were successfully cloned and expressed in E. coli BL21(DE3) cells. The three putrescine transaminases were all shown to prefer diaminoalkanes as substrates and thereby generated cyclic imines from the ω-amino aldehyde intermediates. The addition of a mild chemical reducing agent rapidly reduced the imine intermediate in situ to furnish a range of N-heterocycle products. We applied pATA in a biomimetic synthesis of 2,3-dihydro-1H-indolizinium-containing targets, notably the bioactive alkaloid ficuseptine.
- Slabu, Iustina,Galman, James L.,Weise, Nicholas J.,Lloyd, Richard C.,Turner, Nicholas J.
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p. 1038 - 1042
(2016/04/05)
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- mellow amination by homogeneous catalysis of the method for the production of primary amines
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The invention relates to a method for producing primary amines by means of the alcohol amination of alcohols with ammonia, with water being eliminated. The method comprises the steps of: (a) a homogenously-catalysed reaction of a reaction mixture which contains at least one alcohol, ammonia, at least one non-polar solvent, and at least one catalyst containing at least one element selected from groups 8, 9 and 10 of the periodic table in the liquid phase, a product mixture (P) thus being obtained; (b) separating the phases of product mixture (P) which was obtained in step (a), if necessary after a reduction in temperature, a reduction in pressure and/or the addition of at least one polar solvent with a miscibility gap in relation to the non-polar solvent, and thus obtaining at least one polar product phase (A) and at least one non-polar phase (B) containing at least one portion of the catalyst that was introduced, with said non-polar phase (B) being separated off, (c) returning at least one portion of the non-polar phase (B) into the reaction in step (a), and (d) separating the amination product from the polar product phase (A). The non-polar solvent introduced in (a) and the catalyst introduced in step (a) are selected such that the catalyst in the non-polar phase (B) becomes enriched.
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Paragraph 0265; 0267
(2016/10/09)
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- METHOD FOR PRODUCING ALKANOL AMINES BY HOMOGENEOUSLY CATALYZED ALCOHOL AMINATION
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PROBLEM TO BE SOLVED: To provide a method for producing alkanol amines by alcohol amination of diols using ammonia under elimination of water. SOLUTION: The invention relates to a method for producing alkanol amines which comprise a primary amino group (-NH2) and a hydroxyl group (-OH), by alcohol amination of diols comprising two hydroxyl groups (-OH) using ammonia under elimination of water. The reaction is homogeneously catalyzed in the presence of at least one complex catalyst which contains at least one element selected from groups 8, 9 and 10 of the periodic table and at least one donor ligand. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
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Paragraph 0088; 0099
(2016/10/27)
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- The preparation obtained by homogeneous catalysis mellow amination method of the primary amine
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The invention relates to a method for producing primary amines comprising at least one functional group of formula (-CH2-NH2), by alcohol amination of educts which comprise at least one functional group of formula (-CH2-OH), using ammonia, and elimination of water. The homogeneously catalyzed alcohol amination is carried out in the presence of at least one complex catalyst which contains at least one element selected from the groups 8 and 9 of the periodic table and at least one phosphorus donor ligand of general formula (I).
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Paragraph 0207-0208; 0213
(2017/02/28)
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- Towards a general ruthenium-catalyzed hydrogenation of secondary and tertiary amides to amines
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A broad range of secondary and tertiary amides has been hydrogenated to the corresponding amines under mild conditions using an in situ catalyst generated by combining [Ru(acac)3], 1,1,1-tris(diphenylphosphinomethyl)ethane (Triphos) and Yb(OTf)3. The presence of the metal triflate allows to mitigate reaction conditions compared to previous reports thus improving yields and selectivities in the desired amines. The excellent isolated yields of two scale-up experiments corroborate the feasibility of the reaction protocol. Control experiments indicate that, after the initial reduction of the amide carbonyl group, the reaction proceeds through the reductive amination of the alcohol with the amine arising from collapse of the intermediate hemiaminal.
- Cabrero-Antonino, Jose R.,Alberico, Elisabetta,Junge, Kathrin,Junge, Henrik,Beller, Matthias
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p. 3432 - 3442
(2016/05/19)
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- Joint preparation method for morpholine and imidazolidinone
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The invention discloses a joint preparation method for morpholine and imidazolidinone. The joint preparation method comprises the following steps: uniformly mixing 100 weight parts of diethanol amine, 29 to 58 weight parts of cyanuric chloride and 700 to 790 weight parts of water; reacting for 15 to 16 hours at the temperature of 85 to 95 DEG C; distilling under reduced pressure to remove water; drying distilled residues to obtain a white solid; performing pyrolysis on the white solid to constant weight in inert gas flow at the temperature of 258 to 270 DEG C; simultaneously, cooling and liquefying all pyrolysis gas which is exhausted from the inert gas flow, and introducing the pyrolysis gas into fractionating equipment in a centralized manner; fractionating to obtain morpholine distillate at 128 to 129 DEG C and imidazolidinone distillate at 258 to 265 DEG C; finally, purifying the two distillates and respectively obtaining purified products of the morpholine and the imidazolidinone. According to the joint preparation method for the morpholine and the imidazolidinone, the morpholine and the imidazolidinone can be prepared in a joint manner; the total yield of the morpholine and the imidazolidinone reaches 50.6 percent or above; moreover, a pyrolysis residue by-product with a flame retardant function can also be obtained synchronously, and the yield of the pyrolysis residue by-product is 7.8 to 9.4 percent.
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Paragraph 0017; 0018; 0019; 0120
(2017/01/19)
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- Diethylene glycol a method of low-voltage process for synthesizing diglycol amine
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The invention discloses a method for synthesizing diglycolamine from diglycol by virtue of a low-pressure process. The method comprises the following steps: displacing air in a reactor by use of nitrogen before charging for reaction, and then continuously introducing preheated nitrogen into the reactor so that the temperature of a catalyst in the reactor is increased to the range of 180 to 240 DEG C and the pressure in the reactor is increased to the range of 1.60 to 1.75 MPa; gasifying liquid ammonia, then mixing the gasified ammonia with the hydrogen to obtain a mixed gas, and preheating the mixed gas; mixing diglycol and softened water to obtain a mixed liquid and preheating the mixed liquid; feeding the preheated mixed gas and the preheated mixed liquid into the reactor, performing a gaseous and liquid phase catalyzed ammonolysis reaction in the presence of the catalyst under the conditions of 1.60-1.75MPa and 180-240 DEG C to obtain a crude product; and cooling the obtained crude product and then separating out the gas and the liquid from each other by use of a gas-liquid separator, thereby obtaining the liquid, namely crude diglycolamine. The crude diglycolamine prepared by use of the method for synthesizing the diglycolamine from the diglycol by virtue of the low-pressure process is high in diglycolamine content; the diglycol conversion rate is above 85% and the diglycolamine yield is above 70%.
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Paragraph 0005-0009
(2017/02/23)
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- · Uniform catalyst by using alcohol aminosilicone di-, tri-and a method of manufacturing a polyphenylenepolyamine
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The invention relates to a method for producing primary amines, which contain at least one functional group of the formula (-CH2-NH2) and at least one further primary amino group, by the alcohol amination of reactants, which contain at least one functional group of the formula (-CH2-OH) and at least one further functional group (-X), wherein (-X) is selected from hydroxyl groups and primary amino groups, using ammonia with removal of water, wherein the reaction is carried out in a homogeneously catalyzed manner in the presence of at least one complex catalyst containing at least one element selected from groups 8, 9 and 10 of the periodic table and at least one donor ligand.
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Paragraph 0099; 0108; 0109
(2016/10/09)
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- Catalytic hydrogenation of functionalized amides under basic and neutral conditions
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A new, base-free high turnover number (TON) catalyst for hydrogenation of simple and functionalized amides is prepared by reacting [Ru(η3-C3H5)(Ph2P(CH2)2NH2)2]BF4 and BH4- under hydrogen. The hydrogenation proceeds with C-N cleavage to form the corresponding amine and alcohol. The base-free and base-promoted hydrogenations tolerate alcohols, amines, aromatic bromides, chlorides and fluorides, ethers, certain olefins, and N-heterocyclic rings. The reaction was used to deprotect the amine groups in certain acetyl amides to form, for example, an N-heterocyclic amine containing an aryl bromide. The base-free system also selectively hydrogenates N-acyloxazolidinones without epimerization at the α-position, and reduced β-lactams to form the corresponding amino alcohols.
- John, Jeremy M.,Loorthuraja, Rasu,Antoniuk, Evan,Bergens, Steven H.
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p. 1181 - 1186
(2015/02/19)
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- Highly efficient ruthenium-catalyzed N-formylation of amines with H2 and CO2
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A highly efficient catalyst system based on ruthenium-pincer-type complexes has been discovered for N-formylation of various amines with CO2 and H2, thus affording the corresponding formamides with excellent productivity (turnover numbers of up to 1940000 in a single batch) and selectivity. Using a simple catalyst recycling protocol, the catalyst was reused for 12 runs in N,N-dimethylformamide production without significant loss of activity, thus demonstrating the potential for practical utilization of this cost-effective process.
- Zhang, Lei,Han, Zhaobin,Zhao, Xiaoyu,Wang, Zheng,Ding, Kuiling
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supporting information
p. 6186 - 6189
(2015/05/20)
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- Catalytic carbon-nitrogen bond-forming cross-coupling using N-trimethylsilylamines
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Carbon-nitrogen bond-forming cross-coupling reaction of haloarenes with N-trimethylsilyl (TMS)-substituted secondary and primary arylamines proceeded with the aid of a palladium catalyst and a fluoride activator. Various TMS-N(aryl)2, TMS-NH(aryl), and TMS-N(alkyl)2 reacted to give the corresponding coupled products in high yields. Multi-TMS-amine nucleophiles such as N,N-(TMS)2-aniline and N,N′-Ph2-N,N′-(TMS)2-p-phenylenediamine also participated in this C-N coupling to give multiply C-N coupled products in high yields. The novel C-N cross-coupling reaction was successfully applied to C-N bond-forming polymerization. Relative rates of the cross-coupling of p-bromotoluene with N-TMS-substituted primary and secondary amines showed that N-TMS-diphenylamine reacted faster than N-TMS-N-methylaniline or N-TMS-aniline, and N-TMS-morpholine was the least reactive, indicating that the low basicity of the nitrogen nucleophile is the key for the smooth coupling.
- Minami, Yasunori,Komiyama, Takeshi,Shimizu, Kenta,Hiyama, Tamejiro,Goto, Osamu,Ikehira, Hideyuki
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p. 1437 - 1446
(2015/11/16)
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- CATALYSTS AND PROCESSES FOR THE HYDROGENATION OF AMIDES
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There is provided a process for the reduction of one or more amide moieties in a compound comprising contacting the compound with hydrogen gas and a transition metal catalyst in the presence or absence of a base under conditions for the reduction an amide bond. The presently described processes can be performed at low catalyst loading using relatively mild temperature and pressures, and optionally, in the presence or absence of a base or high catalyst loadings using low temperatures and pressures and high loadings of base to effect dynamic kinetic resolution of achiral amides.
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Paragraph 0269; 0270
(2014/06/24)
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- Synthesis of chromeno[3,4-c][1,2]oxazine-N-oxides via formal [4+2] cycloaddition of 3-nitro-2-trihalomethyl-2H-chromenes with cyclohexanone and pinacolone enamines
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3-Nitro-2-trichloro(trifluoro)methyl-2H-chromenes undergo a formal [4+2] cycloaddition reaction to cyclohexanone and pinacolone enamines, producing chromeno[3,4-c][1,2]benzoxazin-6-oxides with high diastereoselectivity and in good yields. In addition, some novel 2,3,4-trisubstituted chromanes were obtained. The stereochemistry of the products was established based on a 2D NOESY experiment and an X-ray diffraction study.
- Korotaev, Vladislav Yu.,Barkov, Alexey Yu.,Matochkina, Evgeniya G.,Kodess, Mikhail I.,Sosnovskikh, Vyacheslav Ya.
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p. 5161 - 5167
(2014/12/10)
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- In situ DRIFTS study on the synthesis of N-alkylmorpholines
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In situ diffuse reflectance Fourier-transform infrared spectroscopy was used to perform mechanistic investigation on the synthesis of N-alkylmorpholines from diethylene glycol (DEG), alcohol and ammonia. The results showed that the synthesis of N-alkylmorpholines on a heterogeneous catalyst proceeded along the reaction path between DEG and alkylamine when choosing CuO-NiO/γ-Al 2O3 as a suitable catalyst. In addition, the yield of methylmorpholine and ethylmorpholine was 86.4 and 76.6 %, respectively.
- Luo, Chenxi,Luo, Hu,Qian, Chao,Chen, Yunbin,Feng, Lie,Chen, Xinzhi
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p. 2825 - 2835
(2013/07/26)
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- PROCESS FOR PREPARING DI-, TRI- AND POLYAMINES BY HOMOGENEOUSLY CATALYZED ALCOHOL AMINATION
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Process for preparing primary amines which have at least one functional group of the formula (—CH2—NH2) and at least one further primary amino group by alcohol amination of starting materials having at least one functional group of the formula (—CH2—OH) and at least one further functional group (—X), where (—X) is selected from among hydroxyl groups and primary amino groups, by means of ammonia with elimination of water, wherein the reaction is carried out homogeneously catalyzed in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one donor ligand.
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Page/Page column 12; 14
(2012/09/22)
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- PROCESS FOR THE PREPARATION OF PRIMARY AMINES BY HOMOGENEOUSLY CATALYZED ALCOHOL AMINATION
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Preparing a primary amine by alcohol amination of alcohol with ammonia and elimination of water includes reacting, in a homogeneously catalyzed reaction, a mixture of alcohol, ammonia, nonpolar solvent, and catalyst, in a liquid phase, to obtain a product mixture. The process then includes phase separating the product mixture into a polar product phase and a nonpolar product phase, and separating off the nonpolar product phase. At least some of the nonpolar phase returns to the homogenously catalyzed reaction. The process further includes separating off amination product from the polar product phase. At least some of the catalyst is in the nonpolar phase, and the catalyst accumulates in the nonpolar phase.
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Page/Page column 14-15; 17
(2012/09/22)
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- PROCESS FOR PREPARING ALKANOLAMINES BY HOMOGENEOUSLY CATALYZED ALCOHOL AMINATION
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Process for preparing alkanolamines which have a primary amino group (—NH2) and a hydroxyl group (—OH) by alcohol amination of diols having two hydroxyl groups (—OH) by means of ammonia with elimination of water, wherein the reaction is carried out homogeneously catalyzed in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one donor ligand.
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Page/Page column 13-14; 17
(2012/09/22)
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- PROCESS FOR THE PREPARATION OF PRIMARY AMINES BY HOMOGENEOUSLY CATALYZED ALCOHOL AMINATION
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Process for the preparation of primary amines which have at least one functional group of the formula (—CH2—NH2) by alcohol amination of starting materials which have at least one functional group of the formula (—CH2—OH), with ammonia, with the elimination of water, where the alcohol amination is carried out under homogeneous catalysis in the presence of at least one complex catalyst which comprises at least one element selected from groups 8 and 9 of the Periodic Table of the Elements, and also at least one phosphorus donor ligand of the general formula (I).
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Page/Page column 10; 12
(2012/09/22)
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- Reductive cleavage of amides to alcohols and amines catalyzed by well-defined bimetallic molybdenum complexes
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Triple bonds do it! The molybdenum-catalyzed Ci-N bond cleavage of organic amides with hydrosilanes to produce alcohols and amines has been investigated. This work complements previously established protocols that lead to the cleavage of the Ci-O bond. Modified triply bonded dimolybdenum(III) alkoxides have been found to be crucial for tuning the selectivity to Ci-N bond cleavage (see figure). Copyright
- Krackl, Sebastian,Someya, Chika I.,Enthaler, Stephan
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supporting information
p. 15267 - 15271
(2013/01/15)
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- Unprecedented catalytic hydrogenation of urea derivatives to amines and methanol
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Indirect CO2 hydrogenation: Hydrogenation of urea derivatives to the corresponding amines and methanol is reported (see picture). The reaction is catalyzed by a bipyridine-based tridentate PNN Ru(II) pincer complex and proceeds under mild, neutral conditions using 13.6 atm of H2. A mild approach is offered for the indirect hydrogenation of CO2 to methanol as urea derivatives are available from CO2. Copyright
- Balaraman, Ekambaram,Ben-David, Yehoshoa,Milstein, David
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supporting information; experimental part
p. 11702 - 11705
(2012/01/05)
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- A PROCESS FOR THE PREPARATION OF 2-(2-AMINOETHOXY) ETHANOL (2AEE) AND MORPHOLINE WITH 2AEE: MORPHOLINE >3
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The invention relates to a process for the production of 2AEE with selectivity towards 2AEE being significantly higher i.e. the ratio of 2AEE: morpholine > 3. DEG and Ammonia are reacted in a continuous mode in hydrogen atmosphere in the presence of a catalyst at temperature of 150 °C to 250 °C and pressure of 10 Bar to 20 Bar, the products being separated by distillation. The catalyst used is metal and its oxide or metal oxide on silica or alumina support. The molar ratio of ammonia: DEG is > 20 and the molar ratio of hydrogen: DEG is >1, preferably 1-30. The reactants are optionally fed in a downward flow mode. The catalyst charged into the reactor has metal and its oxide or metal oxide equivalent to a metal content of 10 % to 70 % on the support.
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Page/Page column 4
(2011/04/26)
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- CATALYST AND PROCESS FOR PREPARING AN AMINE
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A process for preparing an amine by reacting a primary or secondary alcohol, aldehyde and/or ketone with hydrogen and a nitrogen compound selected from the group of ammonia and primary and secondary amines, in the presence of a supported copper-, nickel- and cobalt-containing catalyst, wherein the catalytically active material of the catalyst, before the reduction thereof with hydrogen, comprises oxygen compounds of aluminum, of copper, of nickel and of cobalt, and in the range from 0.2 to 5.0% by weight of oxygen compounds of tin, calculated as SnO, and catalysts as defined above.
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Page/Page column 12
(2011/06/24)
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- METHOD FOR PRODUCING AN AMINE
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Processes for preparing an amine, which processes comprise: reacting a reactant selected from the group consisting of primary alcohols, secondary alcohols, aldehydes, ketones, and mixtures thereof, with hydrogen and a nitrogen compound selected from the group consisting of ammonia, primary amines, secondary amines and mixtures thereof, in the presence of a zirconium dioxide-, copper- and nickel-containing catalyst; wherein the catalyst comprises a catalytically active composition which comprises, before reduction with hydrogen, oxygen compounds of zirconium, copper, nickel and tin, and 0.5 to 8.0% by weight of an oxygen compound of cobalt, calculated as CoO, and wherein the catalytically active composition does not comprise any ruthenium.
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Page/Page column 11
(2011/04/14)
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- A mild and efficient rhenium-catalyzed transfer hydrogenation of terminal olefins using alcoholysis of amine-borane adducts as a reducing system
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[ReBr2(NO)(CH3CN)(PTA)2] (PTA = 1, 3, 5-triaza-7-phosphaadamantane) catalyzes the alcoholysis of ammonia-borane and amine-boranes and the catalytic transfer hydrogenations of various terminal olefins. Excellent yields were achieved at 70 °C in isopropanol using tBuOK as a co-catalyst affording TOF values up to 396 h-1.
- Dong, Hailin,Berke, Heinz
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experimental part
p. 1803 - 1808
(2011/06/19)
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- Transformations of dialkyl(4-hydroxy-2-butynyl)-(3-phenylallyl)ammonium bromides in an KOH aqueous solution or in the presence of powdered KOH
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Under the action of a twofold excess of KOH and heating in aqueous solution, and also under the conditions of the Stevens rearrangement (with KOH powder and a small amount of methanol) dialkyl-(4-hydroxy-2-butynyl)(3- phenylallyl)ammonium bromides form dialkyl[4-(1-phenylallyl)-2,5-dihydro-2- furyl]amines. Rearrangement-cleavage reaction also occurs under the same conditions.
- Chukhadjian,Gabrielyan,Chukhadjian,Shahkhatuni,Panosyan
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experimental part
p. 418 - 424
(2012/01/13)
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- NOVEL AROMATIC COMPOUND AND POLYARYLENE COPOLYMER HAVING NITROGEN-CONTAINING HETEROCYCLE INCLUDING SULFONIC ACID GROUP IN SIDE CHAIN
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Provided is a solid polymer electrolyte having increased heat resistance and high proton conductivity and a proton conductive membrane composed of the electrolyte. Also provided is a copolymer having a sulfonic acid group. The copolymer includes a repeating unit represented by Formula (1): (in the formula, Y denotes at least one kind of structure selected from the group consisting of —CO—, —SO2—, —SO—, —CONH—, —COO—, —(CF2)l— (l is an integer of 1 to 10), and —C(CF3)2—; W denotes at least one kind of structure selected from the group consisting of a direct bond, —CO—, —SO2—, —SO—, —CONH—, —COO—, —(CF2)l— (l is an integer of 1 to 10), —C(CF3)2—, —O—, and —S—; Z denotes a direct bond or at least one kind of structure selected from the group consisting of —(CH2)l—(l is an integer of 1 to 10), —C(CH3)2—, —O—, —S—, —CO—, and —SO2—; R30 denotes a nitrogen-containing aromatic ring having a substituent represented by —SO3H, —O(CH2)hSO3H, or —O(CF2)hSO3H (h is an integer of 1 to 12); p is an integer of 0 to 10; q is an integer of 0 to 10; r is an integer of 1 to 5; and k is an integer of 0 to 4).
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