96556-05-7Relevant academic research and scientific papers
Well-defined iron complexes as efficient catalysts for green atom-transfer radical polymerization of styrene, methyl methacrylate, and butyl acrylate with low catalyst loadings and catalyst recycling
Nakanishi, So-Ichiro,Kawamura, Mitsunobu,Kai, Hidetomo,Jin, Ren-Hua,Sunada, Yusuke,Nagashima, Hideo
, p. 5802 - 5814 (2014)
Environmentally friendly iron(II) catalysts for atom-transfer radical polymerization (ATRP) were synthesized by careful selection of the nitrogen substituents of N,N,N-trialkylated-1,4,9-triazacyclononane (R3TACN) ligands. Two types of structures were confirmed by crystallography: [(R3TACN)FeX2] complexes with relatively small R groups have ionic and dinuclear structures including a [(R 3TACN)Fe(μ-X)3Fe(R3TACN)]+ moiety, whereas those with more bulky R groups are neutral and mononuclear. The twelve [(R3TACN)FeX2]n complexes that were synthesized were subjected to bulk ATRP of styrene, methyl methacrylate (MMA), and butyl acrylate (BA). Among the iron complexes examined, [{(cyclopentyl) 3TACN}FeBr2] (4b) was the best catalyst for the well-controlled ATRP of all three monomers. This species allowed easy catalyst separation and recycling, a lowering of the catalyst concentration needed for the reaction, and the absence of additional reducing reagents. The lowest catalyst loading was accomplished in the ATRP of MMA with 4b (59ppm of Fe based on the charged monomer). Catalyst recycling in ATRP with low catalyst loadings was also successful. The ATRP of styrene with 4b (117ppm Fe atom) was followed by precipitation from methanol to give polystyrene that contained residual iron below the calculated detection limit (0.28ppm). Mechanisms that involve equilibria between the multinuclear and mononuclear species were also examined. It's easy being green: Structurally well-defined [(R3TACN)FeX 2] complexes realized green atom-transfer radical polymerization by judicious choice of the R group on the N,N,N-trialkylated-1,4,9- triazacyclononane (R3TACN) ligands (see scheme). [{(Cyclopentyl) 3TACN}FeBr2] was the best catalyst for controlled polymerization of all three monomers.
RADIOACTIVE PROBE FOR DETECTING HYDROGEN SULFIDE
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Paragraph 0102; 0103, (2018/03/07)
Provided is a probe for detecting in vivo hydrogen sulfide, specifically, a probe for detecting hydrogen sulfide including a complex compound into which a radioactive isotope Cu is introduced. According to specific embodiments of the present disclosure, as a result of real-time observing animal models, in which hydrogen sulfide involved in various diseases is generated in a large quantity, through optical and nuclear medicine imaging, the probe for detecting hydrogen sulfide according to the present disclosure may selectively bind with hydrogen sulfide to provide images of a site where hydrogen sulfide has abnormally increased in a cell or a tissue, thereby detecting a disease in an unexpected site without affecting the anatomical properties of the body. In addition, the probe for detecting hydrogen sulfide quickly reacts with hydrogen sulfide, thereby solving the existing problem of waiting a predetermined time for testing after an imaging agent is injected. Accordingly, the probe may be effectively used as a means for diagnosing diseases, such as a composition for imaging, an imaging method, etc.
A method for preparing nitrogen heterocyclic
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Paragraph 0027; 0030, (2017/02/24)
The invention discloses a preparation method of azacyclo. The preparation method comprises the following steps of: (1) reacting diethylenetriamine or triethylene tetramine with methylsulfonyl chloride to generate methanesulfonamide; (2) during two-phase reaction, cyclizing compound catalytic cyclization on methanesulfonamide and a compound having the structure shown in a chemical formula (a) under the composite catalysis of benzyl triethylanmine compound and 15-crown-5 at 90 DEG C under a backflow condition; and (3) removing methylsulfonyl from methanesulfonamide azacyclo and performing methylation treatment, wherein X represents bromine, iodine or sulphonate. The preparation method has the advantages that raw materials are low in cost, atom economy is high, and operation is easy and safe. The preparation method is suitable for industrial production.
A paper pulp, fabric bleaching catalyst preparation method of the ligand
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Paragraph 0019, (2017/03/17)
The invention discloses a preparation method of a catalyst ligand for bleaching paper pulp and textile in low temperature. The preparation method comprises following main steps: dissolving diethylenetriamine containing sulfonyl groups in an organic solvent, adding an alkaline reagent and ethylene glycol diacetate, subjecting the mixture to reactions for 6 to 20 hours at the temperature of 80 to 150 DEG C, cooling to the room temperature after the reactions finish, and then filtering to obtain 1,4,7-trisulfonyl-1,4,7-triazacyclononane; adding 1,4,7-trisulfonyl-1,4,7-triazacyclononane in sulfuric acid, stirring for 2 to 12 hours at the temperature of 80 to 130 DEG C, adding in alkali to neutralize after cooling, adding formaldehyde and formic acid, and performing reflux to obtain 1,4,7-trimethyl-1,4,7-triazacyclononane. The preparation method is simple, has the advantages of available materials, and less waste gas, waste water and waste residues, is suitable for industrial production and meets the environmental protection requirements of industry production.
Method of producing polymer using iron complex as catalyst
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Page/Page column 17, (2010/04/23)
The object of the present invention is to provide a method of producing a polymer wherein radical-polymerizable monomers can be polymerized in a quantitative manner in a relatively short time, and a polymer or a block copolymer having at its termini a functional group that can be chemically converted while the polymer or the block copolymer has a high molecular weight can be produced. Furthermore, the object of the present invention is to provide a method of producing a polymer wherein the polymer is re-precipitated in a general solvent by an easy method, and the used iron complexes are recovered in the solvent, thereby recycling the iron complexes.
A heterogeneous, selective oxidation catalyst based on Mn triazacyclononane grafted under reaction conditions
Schoenfeldt, Nicholas J.,Korinda, Andrew W.,Notestein, Justin M.
supporting information; experimental part, p. 1640 - 1642 (2010/07/03)
A unique method has been developed to synthesize an active heterogeneous oxidation catalyst by the in situ grafting of a 1,4,7-trimethyl-1,4,7- triazacyclononane manganese complex on carboxylic acid-functionalized supports serving dual roles as surface tether and necessary co-catalyst, massively increasing total turnovers as compared to the homogeneous analog.
Reusable and environmentally friendly ionic trinuclear iron complex catalyst for atom transfer radical polymerization
Niibayashi, Shota,Hayakawa, Hitoshi,Jin, Ren-Hua,Nagashima, Hideo
, p. 1855 - 1857 (2007/12/27)
Ionic iron complex [(Me3tacn)2Fe2Cl 3]+[(Me3tacn)FeCl3]- (1), which is readily soluble in methanol, acted as a powerful catalyst in controlled radical polymerization of styrene and MMA, and showed promising features of removal from the resulting polymers and was reusable after recovery from the crude products. The Royal Society of Chemistry.
MACROCYCLIC METAL COMPLEXES FOR THEIR USE AS ANTICANCER AGENTS
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Page/Page column 10, (2010/11/25)
In one embodiment the present invention relates to a method of treating cancerous cells in a mammal comprising the steps of administering to the cancerous cells and effective amount of a cyclic amine wherein the cyclic amine contains sulfur or nitrogen and the structure includes an interchealted metal ion.
Method for preparing alkoxyamines from nitroxides
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, (2008/06/13)
The invention relates to a process for preparing alkoxyamines. This process consists in mixing, in an organic solvent, a metal salt, a ligand for the metal, a halocarbon compound ZX and a nitroxide, in keeping the reaction medium stirring at a temperature of between 20° C. and 90° C. until the nitroxide has disappeared, in recovering the organic phase, in washing it with water and then in isolating the alkoxyamine by evaporating the organic solvent under reduced pressure.
Protonation Scheme for some Triaza Macrocycles Studies by Potentiometry and NMR Spectroscopy
Geraldes, Carlos F. G. C.,Sherry, A. Dean,Marques, M. Paula M.,Alpoim, M. Carmen,Cortes, Sergio
, p. 137 - 146 (2007/10/02)
A series of triaza macrocyclic tricarboxylate ligands with ring sizes of nine to twelve (NOTA, DETA, UNTA and DOTRA) have been synthesized.Their acid-base properties and protonation sequence have been established and compared with those of the corresponding cyclic triamines and trimethyl cyclic triamines, using potentiometric measurements and 1H NMR pH titrations.The first protonation constant of the carboxylate ligands is very high, and larger than the value for the parent cyclic amines.It is also very sensitive to the presence of Na+ ions in solution.The first two protonation constants correspond to protonation of the ring nitrogens, and their increase with ring size is non-monotonic, reflecting pH-dependent conformational effects.These effects, due to electrostatic interactions as well as to hydrogen bond formation, caused difficulties in the application of methods (previously used for noncyclic polyaminocarboxylates) to obtain the protonation sequence from the 1H NMR pH titrations, similar to a previous occurence for tetraaza macrocycles.By studying the pH dependence of the shielding parameters, CN and CN', the protonation sequences were then obtained.For each of the four compounds studied, two nitrogen atoms are protonated before the carboxylate groups.Formation of hydrogen bonds between protonated nitrogens and non-protonated carboxylates affects the basicity of the latter, reducing the flexibility of these ligands in certain pH intervals.

