- Extraction of U(VI) with N,N'-dimethyl-N,N'-dioctylmalonamide from nitrate media
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The extraction of uranyl nitrate with the novel extractant N,N '-dimethyl-N,N '-dioctylmalonamide (DMDOMA) from aqueous sodium nitrate (and nitric acid) was investigated. The extraction mechanism was established and the stoichiometry of the main extracted species confirms to UO2(NO 3)2 · DMDOMA. The IR spectral study was also made of the extracted species. Methyl substituent improves the extraction ability of malonamide for U(VI) compared with that of N,N,N ', N '-tertrabutylmalonamide (TBMA). Pleiades Publishing, Ltd., 2010.
- Cui, Yu,Hu, Yufen,Zhang, Yanju,Yin, Shaohong,Sun, Guoxin
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Read Online
- A METHOD FOR PREPARING ALKYLATED AMINES
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The present invention pertains to a method for preparing an alkylated amine by reacting a primary or secondary amine with an alcohol in the presence of hydrogen, a metal catalyst supported by photosensitive titanium oxide, and UV irradiation. Advantageously, the reaction can be carried out under mild reaction conditions.
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Page/Page column 21-32; 33
(2021/09/11)
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- Dimethylamination of Primary Alcohols Using a Homogeneous Iridium Catalyst: A Synthetic Method for N, N-Dimethylamine Derivatives
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A new catalytic system for N,N-dimethylamination of primary alcohols using aqueous dimethylamine in the absence of additional organic solvents has been developed. The reaction proceeds via borrowing hydrogen processes, which are atom-efficient and environmentally benign. An iridium catalyst bearing an N-heterocyclic carbene (NHC) ligand exhibited high performance, without showing any deactivation under aqueous conditions. In addition, valuable N,N-dimethylamine derivatives, including biologically active and pharmaceutical molecules, were synthesized. The practical application of this methodology was demonstrated by a gram-scale reaction.
- Jeong, Jaeyoung,Fujita, Ken-Ichi
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p. 4053 - 4060
(2021/03/09)
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- Ru-Catalyzed Selective Catalytic Methylation and Methylenation Reaction Employing Methanol as the C1 Source
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Methanol can be employed as a green and sustainable methylating agent to form C-C and C-N bonds via borrowing hydrogen (BH) methodology. Herein we explored the activity of the acridine-derived SNS-Ru pincer for the activation of methanol to apply it as a C1 building block in different reactions. Our catalytic system shows great success toward the β-C(sp3)-methylation reaction of 2-phenylethanols to provide good to excellent yields of the methylated products. We investigated the mechanistic details, kinetic progress, and temperature-dependent product distribution, which revealed the slow and steady generation of in situ formed aldehyde, is the key factor to get the higher yield of the β-methylated product. To establish the environmental benefit of this reaction, green chemistry metrics are calculated. Furthermore, dimerization of 2-naphthol via methylene linkage and formation of N-methylation of amine are also described in this study, which offers a wide range of substrate scope with a good to excellent yield.
- Biswas, Nandita,Srimani, Dipankar
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p. 10544 - 10554
(2021/07/31)
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- N-Methylation of amines and nitroarenes with methanol using heterogeneous platinum catalysts
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We report herein the selective N-methylation of amines and nitroarenes with methanol under basic conditions using carbon-supported Pt nanoparticles (Pt/C) as a heterogeneous catalyst. This method is widely applicable to four types of N-methylation reactions: (1) N,N-dimethylation of aliphatic amines under N2, (2) N-monomethylation of aliphatic amines under 40 bar H2, (3) N-monomethylation of aromatic amines under N2, and (4) tandem synthesis of N-methyl anilines from nitroarenes and methanol under 2 bar H2. All these reactions under the same catalytic system showed high yields of the corresponding methylamines for a wide range of substrates, high turnover number (TON), and good catalyst reusability. Mechanistic studies suggested that the reaction proceeded via a borrowing hydrogen methodology. Kinetic results combined with density functional theory (DFT) calculations revealed that the high performance of Pt/C was ascribed to the moderate metal–hydrogen bond strength of Pt.
- Jamil, Md.A.R.,Touchy, Abeda S.,Rashed, Md. Nurnobi,Ting, Kah Wei,Siddiki, S.M.A. Hakim,Toyao, Takashi,Maeno, Zen,Shimizu, Ken-ichi
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- Selective Monomethylation of Amines with Methanol as the C1 Source
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The N-monomethyl functionality is a common motif in a variety of synthetic and natural compounds. However, facile access to such compounds remains a fundamental challenge in organic synthesis owing to selectivity issues caused by overmethylation. To address this issue, we have developed a method for the selective, catalytic monomethylation of various structurally and functionally diverse amines, including typically problematic primary aliphatic amines, using methanol as the methylating agent, which is a sustainable chemical feedstock. Kinetic control of the aliphatic amine monomethylation was achieved by using a readily available ruthenium catalyst at an adequate temperature under hydrogen pressure. Various substrates including bio-related molecules and pharmaceuticals were selectively monomethylated, demonstrating the general utility of the developed method.
- Choi, Geunho,Hong, Soon Hyeok
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supporting information
p. 6166 - 6170
(2018/04/30)
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- Photometric Characterization of the Reductive Amination Scope of the Imine Reductases from Streptomyces tsukubaensis and Streptomyces ipomoeae
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Imine reductases (IREDs) have emerged as promising enzymes for the asymmetric synthesis of secondary and tertiary amines starting from carbonyl substrates. Screening the substrate specificity of the reductive amination reaction is usually performed by time-consuming GC analytics. We found two highly active IREDs in our enzyme collection, IR-20 from Streptomyces tsukubaensis and IR-Sip from Streptomyces ipomoeae, that allowed a comprehensive substrate screening with a photometric NADPH assay. We screened 39 carbonyl substrates combined with 17 amines as nucleophiles. Activity data from 663 combinations provided a clear picture about substrate specificity and capabilities in the reductive amination of these enzymes. Besides aliphatic aldehydes, the IREDs accepted various cyclic (C4–C8) and acyclic ketones, preferentially with methylamine. IR-Sip also accepted a range of primary and secondary amines as nucleophiles. In biocatalytic reactions, IR-Sip converted (R)-3-methylcyclohexanone with dimethylamine or pyrrolidine with high diastereoselectivity (>94–96 % de). The nucleophile acceptor spectrum depended on the carbonyl substrate employed. The conversion of well-accepted substrates could also be detected if crude lysates were employed as the enzyme source.
- Matzel, Philipp,Krautschick, Lukas,H?hne, Matthias
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p. 2022 - 2027
(2017/10/07)
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- One-pot anti-markovnikov hydroamination of unactivated alkenes by hydrozirconation and amination
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A one-pot anti-Markovnikov hydroamination of alkenes is reported. The synthesis of primary and secondary amines from unactivated olefins was accomplished in the presence of a variety of functional groups. Hydrozirconation, followed by amination with nitrogen electrophiles, provides exclusive anti-Markovnikov selectivity. Most products are isolated in high yields without the use of column chromatography.
- Strom, Alexandra E.,Hartwig, John F.
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p. 8909 - 8914
(2013/09/24)
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- Synthesis of nonsymmetrical dialkylamines on the basis of diphenylphosphinic amides
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A facile method for the synthesis of nonsymmetrical dialkylamines (C nH2n+1)2NH (n = 1-12) using the Ph 2P(O) protecting group was developed. The method includes successive transformation of monoalkylamines to primary diphenylphosphinic N-alkylamides Ph2P(O)NHR' (R' = CnH2n+1, n = 1-12) by the Todd-Atherton reaction, phase transfer N-alkylation of these compounds, and hydrolysis of the secondary amides Ph2P(O)NR'R″ thus formed. When the (EtO)2P(O) and Bu2P(O) protecting groups are used, N-alkylation of primary amides is accompanied by the formation of Et-O and P-N bond cleavage products, respectively. A study of the stability of the N-alkylamides R2P(O)NHR' (R = Ph, p-MeC6H4, p-CIC6H4, Bu) under strong alkaline conditions used in the phase transfer N-alkylation showed that an increase in the electron-donating ability of substituents at both the nitrogen atom and the phosphorus atom results in a decrease in the degree of P-N bond cleavage. The primary and secondary diphenylphosphinic amides containing a β-hydroxyethyl group at the nitrogen atom are extremely unstable under the alkaline conditions and are converted quantitatively to the diphenylphosphinic acid salt.
- Bondarenko,Kharlamov,Vendilo
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experimental part
p. 1872 - 1885
(2011/01/06)
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- Gas-phase selective N-alkylation of amines with alcohols over γ- alumina
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Gas-phase conditions were successfully used for fine chemistry, in the N-alkylation of amines with alcohols as alkylating agents and γ-alumina as a catalyst. The method is also suitable for chiral compounds.
- Valot, Frederic,Fache, Fabienne,Jacquot, Roland,Spagnol, Michel,Lemaire, Marc
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p. 3689 - 3592
(2007/10/03)
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- Mono-N-alkylation of α-Aminoacetonitriles. A Novel Route to Unsymmetrical Secondary Amines
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Mannich-type condensation products of an aldehyde with an α-aminoacetonitrile and benzotriazole are treated with sodium borohydride or with a Grignard reagent to give unsymmetrical N,N-dialkylaminoacetonitriles, which, on decyanomethylation provide unsymmetrical secondary amines.
- Katritzky, Alan R.,Latif, Muhammad,Urogdi, Laszlo
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p. 667 - 672
(2007/10/02)
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- N-Monomethylation of Primary Amines via Intermediate Benzothiazol-2(3H)-imines
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Aliphatic and aromatic amines are converted by successive treatment with (i) 3-methyl-2-methylthiobenzothiazolium iodide, (ii) methyl iodide or toluene-p-sulphonate, and (iii) butylamine, in high yield under mild conditions into their mono-N-methyl derivatives.
- Katritzky, Alan R.,Drewniak, Malgorzata,Aurrecoechea, Jose M.
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p. 2539 - 2542
(2007/10/02)
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- Process for recovering actinides and/or lanthanides
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This invention relates to a process of recovering trivalent actinides, trivalent lanthanides or mixtures thereof from an aqueous acid solution by contacting the aqueous solution with an organic solution containing the diamides of the formula: STR1 where R is C2 -C10 alkyl. This process affords a good extraction efficiency level for the recovery of lanthanides and actinides, both of which are present in the trivalent state, or mixtures thereof, from installations for the reprocessing of irradiated nuclear fuels.
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- Hair dyeing compositions containing quaternized polymer
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A quaternized polymer for use as a cosmetic agent, has recurring units of the formula STR1 wherein R is lower alkyl or -CH2 -CH2 OH; R' is an aliphatic, alicyclic or arylaliphatic radical containing a maximum of 20 carbon atoms, or R and R' together with the nitrogen atom to which they are attached form a heterocycle capable of containing a heteroatom other than nitrogen; A is a divalent group selected from (1) o-, m- or p-xylylidene of the formula STR2 wherein x, y and t are whole numbers ranging from 0 to 11 such that the sum (x+y+t) is greater than or equal to 0 and lower than 18, and E and K represent hydrogen or an aliphatic radical having less than 18 carbon atoms, (3) --(CH2)n --S--(CH2)n --, (4) --(CH2)n --O--(CH2)n --, (5) --(CH2)n --S--S--(CH2 (n --, (6) --(CH2)n --SO--(CH2)n --, (7) --(CH2)n --SO2 --(CH2)n --and STR3 wherein n is equal to 2 or 3; B represents a divalent group selected from (1) o-, m- or p-xylylidene of the formula STR4 wherein D and G represent hydrogen or an aliphatic radical having less than 18 carbon atoms and v, z and u are whole numbers ranging from 0 to 11, with two of v, z and u simultaneously being capable of being 0, such that the sum (v+z+u) is greater than or equal to 1 and lower than 18 and such that the sum (v+z+u) is greater than 1 when the sum (x+y+t) is equal to 0, STR5 (4) --(CH2)n --O--(CH2)n -- wherein n is 2 or 3; and X? is an anion derived from an organic or mineral acid. The quaternized polymer is employed in cosmetic compositions for the hair and skin.
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- Novel Functional Group Selectivity in Reductions with Lithium Borohydride in Mixed Solvents Containing Methanol
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Primary amides were reduced selectively in the presence of carboxylic acid salts or secondary aliphatic amides by lithium borohydride in diglyme-methanol, and esters and epoxides were selectively reduced rapidly by LiBH4 in the presence of nitro, chloro, or amide groups in ether containing a small amount of methanol.
- Soai, Kenso,Ookawa, Atsuhiro,Hayashi, Hiroshi
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p. 668 - 669
(2007/10/02)
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- A HIGHLY EFFICIENT AND GENERAL N-MONOMETHYLATION OF FUNCTIONALIZED PRIMARY AMINES VIA FORMYLATION -- BORANE:METHYL SULFIDE REDUCTION
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Formylation of functionalized primary aromatic and aliphatic amines with acetic formic anhydride (AFA) followed by borane:methyl sulfide reduction in the same pot affords the corresponding N-methylamines in excellent isolated yields, uncontaminated by bis alkylation; the reaction sequence is applicable to even very weakly basic and sterically hindered amines.
- Krishnamurthy, S.
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p. 3315 - 3318
(2007/10/02)
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- Quaternized polymer for use as a cosmetic agent in cosmetic compositions for the hair and skin
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A quaternized polymer for use as a hair or skin cosmetic agent, has recurring units of the formula STR1 wherein R is lower alkyl or --CH2 --CH2 OH; R' is an aliphatic, alicyclic or arylaliphatic radical containing up to 20 carbon atoms, or R and R' together with the nitrogen atom to which they are attached form a heterocycle capable of containing a heteroatom other than nitrogen; A is (1) o-, m- or p-xylylidene of the formula STR2 STR3 wherein x, y and t are whole numbers ranging from 0 to 11 so the sum (x+y+t) is greater than or equal to 0 and lower than 18, and E and K represent hydrogen or an aliphatic radical having less than 18 carbon atoms, (3) --(CH2)n --S--(CH2)n --, (4) --(CH2)n --O--(CH2)n --, (5) --(CH2)n --S--S--(CH2)n --, (6) --(CH2)n --SO--(CH2)n --, (7) --(CH2)n --SO2 --(CH2)n --or STR4 wherein n is equal to 2 or 3; B represents (1) o-, m- or p-xylylidene of the formula STR5 STR6 wherein D and G represent hydrogen or an aliphatic radical having less than 18 carbon atoms and v, z and u are whole numbers ranging from 0 to 11, with two of v, z and u simultaneously being capable of being 0, so the sum (v+z+u) is greater than or equal to 1 and lower than 18 and so the sum (v+z+u) is greater than 1 when the sum (x+y+t) is equal to 0, (3) STR7 or (4) --(CH2)n --O--(CH2)n -- wherein n is 2 or 3; and X? is an anion derived from an organic or mineral acid.
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