scholarly journals (Thio)urea-mediated synthesis of functionalized six-membered rings with multiple chiral centers

2016 ◽  
Vol 12 ◽  
pp. 462-495 ◽  
Author(s):  
Giorgos Koutoulogenis ◽  
Nikolaos Kaplaneris ◽  
Christoforos G Kokotos
Keyword(s):  
Asymmetric Catalysis ◽  
Secondary Amine ◽  
Tertiary Amine ◽  
Primary Amine ◽  
Membered Ring ◽  
Chiral Centers ◽  
Synthetic Chemist ◽  
Functionalization Reaction

Organocatalysis, now running its second decade of life, is being considered one of the main tools a synthetic chemist has to perform asymmetric catalysis. In this review the synthesis of six-membered rings, that contain multiple chiral centers, either by a ring closing process or by a functionalization reaction on an already existing six-membered ring, utilizing bifunctional (thio)ureas will be summarized. Initially, the use of primary amine-thioureas as organocatalysts for the above transformation is being discussed, followed by the examples employing secondary amine-thioureas. Finally, the use of tertiary amine-thioureas and miscellaneous examples are presented.

Formic acid dehydrogenation over Pd NPs supported on amine-functionalized SBA-15 catalysts: structure–activity relationships

2017 ◽  
Vol 5 (31) ◽  
pp. 16150-16161 ◽  
Author(s):  
Katherine Koh ◽  
Mina Jeon ◽  
Chang Won Yoon ◽  
Tewodros Asefa
Keyword(s):  
Formic Acid ◽  
Secondary Amine ◽  
Tertiary Amine ◽  
Primary Amine ◽  
Catalytic Properties ◽  
Pd Nanoparticles ◽  
Structure Activity Relationships ◽  
Amine Functionalized ◽  
Structure Activity ◽  
Formic Acid Dehydrogenation

A series of Pd/SBA-15-amine materials (where “Amine” is primary amine, secondary amine and tertiary amine) containing Pd nanoparticles are synthesized and their catalytic properties for formic acid dehydrogenation are investigated.

scholarly journals Donor–acceptor Stenhouse adduct-grafted polycarbonate surfaces: selectivity of the reaction for secondary amine on surface

2018 ◽  
Vol 5 (7) ◽  
pp. 180207
Author(s):  
Sukhdeep Singh ◽  
Patrick Mai ◽  
Justyna Borowiec ◽  
Yixin Zhang ◽  
Yong Lei ◽  
...  
Keyword(s):  
Visible Light ◽  
Secondary Amine ◽  
Tertiary Amine ◽  
Primary Amine ◽  
Polymer Surface ◽  
Photochromic Properties ◽  
Amine Functionalized ◽  
Plasma Activation ◽  
Donor Acceptor

Donor–acceptor Stenhouse adducts (DASAs) are gaining attention from organic and material chemists due to their visible light-stimulated photochromic properties. In this report, we present a facile method for grafting coloured triene on polycarbonate surface, without involving any pre-treatments like plasma activation, etc. The chemoselectivity of carbonate with a primary amine and Meldrum's activated furan (MAF) with polymer bound secondary amine has been exploited to graft photoswitchable DASA on the polymer surface. Primary, secondary and tertiary amine-functionalized polycarbonate surfaces have been prepared to evaluate the reactivity of amine with MAF.

Salts of 3,5-dinitrobenzoic acid with organic diamines: hydrogen-bonded supramolecular structures in one, two and three dimensions

2001 ◽  
Vol 57 (2) ◽  
pp. 201-212 ◽  
Author(s):  
Colin J. Burchell ◽  
Christopher Glidewell ◽  
Alan J. Lough ◽  
George Ferguson
Keyword(s):  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Secondary Amine ◽  
Tertiary Amine ◽  
Primary Amine ◽  
Three Dimensional ◽  
Supramolecular Structures ◽  
Three Dimensions ◽  
Two Dimensional ◽  
One Dimensional

The trigonally trisubstituted carboxylic acid 3,5-dinitrobenzoic acid, (O2N)2C6H3COOH, forms 2:1 salts with a range of organic diamines L, with the general composition [LH2]2+·[{(O2N)2C6H3COO}−]2. When L is a bis-tertiary amine the hard N—H...O hydrogen bonds generate finite three-component aggregates, anion...cation...anion, and these aggregates are further linked by soft C—H...O hydrogen bonds to form one-dimensional molecular ladders when L is N,N,N′,N′′-tetramethyl-1,2-diaminoethane and chains of rings when L is 4,4′-dipyridylethane or 4,4′-dipyridylethene; two-dimensional sheets are formed when L is 1,4-diazabicyclo[2.2.2]octane and a three-dimensional framework is formed when L is N,N′-dimethylpiperazine. When L is the bis-secondary amine piperazine, the hard N—H...O and soft C—H...O hydrogen bonds each generate continuous motifs in the form of distinct chains of rings, the combination of which generates sheets, while when L is the bis-primary amine 1,2-diaminoethane the hard N—H...O hydrogen bonds alone generate a three-dimensional framework.

scholarly journals Colorimetric Amine Detection by Vanillin-Hydrazone Derivatives during Chicken Meat Spoilage

2021 ◽  
Vol 50 (4) ◽  
pp. 989-996
Author(s):  
Bambang Purwono ◽  
Beta Achromi Nurohmah ◽  
Suharman Suharman
Keyword(s):  
Secondary Amine ◽  
Tertiary Amine ◽  
Primary Amine ◽  
Room Temperature ◽  
Condensation Reaction ◽  
Chicken Meat ◽  
Color Changes ◽  
Naked Eye ◽  
Meat Spoilage ◽  
Amine Detection

Two vanillin-hydrazone compounds as the colorimetric amine detection during chicken meat spoilage are described. Two hydrazone compounds (1 and 2) have been synthesized from the condensation reaction of vanillin with phenylhydrazine and 2,4-dinitrophenylhydrazine. Their properties for colorimetric recognition of amine were determined by the naked eye and UV-vis spectra. Their properties as amine indicators were investigated toward primary amine: butylamine (BA); secondary amine: dimethylamine (DMA), diethylamine (DEA); tertiary amine: triethylamine (TEA), and also ammonia (Amm). The hydrazone 1 in DMSO showed no significant color changes (colorless) after the addition of amines solution. Hydrazone 2 (5×10-5 M in DMSO) showed color changes from yellow to violet in the presence of ammonia, DEA and BA, to reddish-violet for DMA, and light brown after addition of TEA solutions. The colorimetric amine detection by vanillin-hydrazone 2 could recognize the real amine during chicken meat spoilage from yellow to light brown after 24 h storage at room temperature.

Regio-, Stereo- and Enantioselective α-Addition of Carbonyl Nucleo-philes to Allenamides Catalyzed by a Synergistic Copper/Enamine System

2020 ◽  
Author(s):  
Rémi Blieck ◽  
Sebastien Lemouzy ◽  
Marc Taillefer ◽  
Florian Monnier
Keyword(s):  
Catalytic System ◽  
Secondary Amine ◽  
Primary Amine ◽  
Synergistic Catalysis ◽  
Enantioselective Addition ◽  
Amine Catalysts

A dual copper/enamine catalytic system is found to enable an intermolecular enantioselective α-addition of various carbonyl nucleophiles to allenamides. Secondary amine catalysts allowed the highly enantioselective addition of aldehydes, while using primary amine catalysts led to the enantioselective addition of ketoester nucleophiles. The process was found to be highly regio-, stereo- and enantio-selective and represented the first allene hydrofunctionalization using an synergistic catalysis involving copper

Carbonyl catalysis enables a biomimetic asymmetric Mannich reaction

Science ◽  
2018 ◽  
Vol 360 (6396) ◽  
pp. 1438-1442 ◽  
Author(s):  
Jianfeng Chen ◽  
Xing Gong ◽  
Jianyu Li ◽  
Yingkun Li ◽  
Jiguo Ma ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
High Activity ◽  
Asymmetric Catalysis ◽  
Carbonyl Group ◽  
Mannich Reaction ◽  
Primary Amine ◽  
Chiral Amines ◽  
Carbonyl Groups ◽  
Diphenylphosphinyl Imines

Chiral amines are widely used as catalysts in asymmetric synthesis to activate carbonyl groups for α-functionalization. Carbonyl catalysis reverses that strategy by using a carbonyl group to activate a primary amine. Inspired by biological carbonyl catalysis, which is exemplified by reactions of pyridoxal-dependent enzymes, we developed an N-quaternized pyridoxal catalyst for the asymmetric Mannich reaction of glycinate with aryl N-diphenylphosphinyl imines. The catalyst exhibits high activity and stereoselectivity, likely enabled by enzyme-like cooperative bifunctional activation of the substrates. Our work demonstrates the catalytic utility of the pyridoxal moiety in asymmetric catalysis.

Aminkomplexe des Goldes, Teil 9: Gold(I)-halogenid-Komplexe mit primären und azyklischen sekundären Aminen und ihre Oxidation zu Gold(III)-Derivaten

2018 ◽  
Vol 73 (1) ◽  
pp. 43-74 ◽  
Author(s):  
Cindy Döring ◽  
Peter G. Jones
Keyword(s):  
Hydrogen Bonds ◽  
Structure Analysis ◽  
Secondary Amine ◽  
Primary Amine ◽  
Solvent Free ◽  
Secondary Amines ◽  
Primary Amines ◽  
Direct Reaction ◽  
X Ray

AbstractThe reaction of (tht)AuX (X=Cl or Br; tht=tetrahydrothiophene) with various primary amines L leads to products of the form [L2Au]+X−. Packing diagrams of the corresponding structures are dominated by N–H···X hydrogen bonds and (in some cases) aurophilic contacts. The cyclohexylamine derivative was already known as its dichloromethane ⅔-solvate; we have isolated the solvent-free compound and its pentane ¼-solvate, which all show different packing patterns. With acyclic secondary amines, the products are more varied; LAuX and [L2Au]+[AuX2]− were also found. These gold(I) products were generally formed in satisfactory quantities. The attempted oxidation to Au(III) derivatives with PhICl2 or Br2 proved impossible for the primary amine derivatives [although isopropylamine-trichloridogold(III) was obtained unexpectedly from the corresponding cyanide] and unsatisfactory for the secondary amine derivatives. Products LAuX3 and [L2AuX2]+[AuX4]− were identified but were formed in disappointing yields. In isolated cases protonated products (LH)+[AuCl4]−, (LH+)3[AuCl4]−(Cl−)2 or [(Et2N)2CH]+[AuBr4]− were formed, presumably by involvement of the dichloromethane solvent and/or adventitious water. Here also the yields were poor, and some products arose as mixtures. Direct reaction of amines with AuCl3 or (tht)AuX3 was also unsuccessful. All products were characterized by X-ray structure analysis.

Synthese von vier- und achtgliedrigen Heterocyclen, die Schwefel, Stickstoff und Phosphor enthalten, und die Röntgenstrukturanalyse eines phosphorhaltigen achtgliedrigen SN-Ringes / Synthesis of Four- and Eight-Membered Heterocycles Containing Sulfur, Nitrogen and Phosphorus and the X-ray Structure of a Phosphorus-Containing Eight-Membered SN-Ring

1980 ◽  
Vol 35 (9) ◽  
pp. 1130-1136 ◽  
Author(s):  
Herbert W. Roesky ◽  
Sushil K. Mehrotra ◽  
Christoph Platte ◽  
Djamrnschid Amirzadeh-Asl ◽  
Bernhard Roth
Keyword(s):  
Tertiary Amine ◽  
Phosphorus Atom ◽  
Mass Spectra ◽  
Phosphorus Pentachloride ◽  
Membered Ring ◽  
Phosphonium Salts ◽  
Nitrogen And Phosphorus ◽  
Orthorhombic Space Group ◽  
X Ray ◽  
Phosphorus Containing

Eight-membered rings of the composition [SO2(NR)2PR′]2 3a-d with R = CH3, C2H5, and R′ = CH3, C6H5, were prepared from substituted sulfamides and dichlorophosphanes in the presence of a tertiary amine. These molecules were characterized on the basis of 1H and 31P NMR investigations and of mass spectra. 3 a reacts with phosphorus pentachloride to yield the spirocyclic derivative 4 with the phosphorus atom in the center of two four-membered rings. Methyliodide reacts with 3 a and 3 b under opening of the eight- membered ring and formation of phosphonium salts. The structure of 3 b is discussed in detail. 8b crystallizes in the orthorhombic space group Pna 21 with a = 12.60(0), b = 13.27(1), c = 12.62(4) Å.

Ethylenediamine-functionalized magnetic Fe3O4@SiO2 nanoparticles: cooperative trifunctional catalysis for selective synthesis of nitroalkenes

RSC Advances ◽  
2015 ◽  
Vol 5 (90) ◽  
pp. 73684-73691 ◽  
Author(s):  
Fengjun Xue ◽  
Yahao Dong ◽  
Peibo Hu ◽  
Yanan Deng ◽  
Yuping Wei
Keyword(s):  
Secondary Amine ◽  
Primary Amine ◽  
Sio2 Nanoparticles ◽  
Selective Synthesis ◽  
Oh Groups ◽  
Highly Active ◽  
Magnetic Fe3o4

The designed nanocatalyst Fe3O4@SiO2–NH2 was highly active for selective synthesis of nitroalkenes through cooperative trifunctional catalysis of primary amine, secondary amine and Si–OH groups.

A Simple Method of Protecting a Secondary Amine with Tert Butyloxycarbonyl (Boc) in the Presence of a Primary Amine

1992 ◽  
Vol 22 (16) ◽  
pp. 2357-2360 ◽  
Author(s):  
John D. Prugh ◽  
Laura A. Birchenough ◽  
Melissa S. Egbertson
Keyword(s):  
Secondary Amine ◽  
Primary Amine ◽  
Simple Method
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