Synthesis of 2-substituted 5-arylidenethiazolin-4-ones from α,β-unsaturated acyl isothiocyanates

1981 ◽  
Vol 46 (2) ◽  
pp. 436-445 ◽  
Author(s):  
Peter Kutschy ◽  
Milan Dzurilla ◽  
Pavol Kristian ◽  
Kvetoslava Kutschyová
Keyword(s):  
Primary Amines ◽  
Reaction Conditions ◽  
H Nmr ◽  
Unsaturated Acyl ◽  
Independent Synthesis

α,β-Unsaturated acyl isothiocyanates react with N-methylaniline to give thioureas which, when treated with bromine in chloroform, afford benzothiazoline derivatives. Under the same reaction conditions primary amines, diethylamine, piperidine and morpholine furnish 2-substituted 5-arylidenethiazolin-4-ones. Their structure was corroborated by an independent synthesis and on the basis of spectral (IR, 1H-NMR and mass) evidence.

1H-NMR Analysis of Degree of Substitution in N,O-Carboxymethyl Chitosans from Various Chitosan Sources and Types

2012 ◽  
Vol 506 ◽  
pp. 158-161 ◽  
Author(s):  
A. Jaidee ◽  
Pornchai Rachtanapun ◽  
S. Luangkamin
Keyword(s):  
Chemical Structure ◽  
Carboxymethyl Chitosan ◽  
Degree Of Substitution ◽  
Resonance Spectroscopy ◽  
Nmr Analysis ◽  
Reaction Conditions ◽  
H Nmr ◽  
Fourier Transformed Infrared Spectroscopy ◽  
Chitosan Oligomer ◽  
Ft Ir

N,O-Carboxymethyl chitosans were synthesized by the reaction between shrimp, crab and squid chitosans with monochloroacetic acid under basic conditions at 50°C. The mole ratio of reactants was obtained from various reaction conditions of shrimp chitosan polymer and oligomer types. The mole ratio 1:12:6 of chitosan:sodium hydroxide:monochloroacetic acid was used for preparing carboxymethyl of chitosan polymer types while carboxymethyl of chitosan oligomer types were used the mole ratio 1:6:3 of chitosan:sodium hydroxide:monochloroacetic acid. The chemical structure was analyzed by fourier transformed infrared spectroscopy (FT-IR) and proton nuclear magnatic resonance spectroscopy (1H-NMR). The FT-IR was used for confirm the insertion of carboxymethyl group on chitosan molecules. The 1H-NMR was used for determining the degree of substitution (DS) of carboxymethylation at hydroxyl and amino sites of chitosans. Carboxymethyl chitosan samples had the total DS of carboxymethylation ranging from 1.0-2.2. The highest of DS of carboxymethylation was from shrimp chitosan oligomer type.

scholarly journals Metallkomplexe mit Tetrapyrrol-Liganden, XXXVIII [1]. Zur Kenntnis der Alkyl- und Arylimidovanadium(IV)-Porphyrine / Metal Complexes with Tetrapyrrole Ligands, XXXVIII [1]. On the Knowledge of Alkyl- and Arylimidovanadium(IV) Porphyrins

1985 ◽  
Vol 40 (10) ◽  
pp. 1362-1370 ◽  
Author(s):  
Johann W. Buchler ◽  
Stefan Pfeifer
Keyword(s):  
Mass Spectra ◽  
Nmr Spectra ◽  
Primary Amines ◽  
Reactive Intermediate ◽  
H Nmr ◽  
Vanadyl Complex ◽  
Elemental Analyses ◽  
Paramagnetic Metal ◽  
Paramagnetic Complexes ◽  
Proton Resonances

A series of novel alkyl or aryiimidovanadium(IV) 5,10,15,20-tetra(p-tolyl)porphyrinates, VNR(TTP) (4a-4g), is described. They are obtained from the vanadyl complex, VO(TTP) (2a) via the reactive intermediate VCl2(TTP) (3b) which undergoes aminolysis with the respective primary amines RNH2 (R = tBu, Ph, pTol, pClPh, pAnis, pBiph, ptBuPh)**. The formulae are proved by elemental analyses and mass spectra. The paramagnetic complexes are stable to water and may thus be purified by chromatography but are hydrolyzed to give 2 a on treatment with acetic acid. The UV/VIS and 1H NMR spectra of 4a-4g are of the same type as 2a, but the former are slightly hypsochromically shifted, and the latter do not show the proton resonances of the organylimide ligands due to the proximity of the paramagnetic metal center.

scholarly journals Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions

2013 ◽  
Vol 9 ◽  
pp. 2344-2353 ◽  
Author(s):  
Sudipta Pathak ◽  
Kamalesh Debnath ◽  
Animesh Pramanik
Keyword(s):  
Sulfuric Acid ◽  
Low Cost ◽  
Solvent Free ◽  
Primary Amines ◽  
Solid Catalyst ◽  
Silica Sulfuric Acid ◽  
Reaction Conditions ◽  
One Pot ◽  
Solvent Free Conditions ◽  
Solvent Free Reaction

A convenient and efficient methodology for the synthesis of densely substituted pyrrole-fused isocoumarins, which employs solid-supported silica sulfuric acid (SSA) as catalyst, has been developed. When the mixture of ninhydrin adducts of acetylacetone/ethyl acetoacetate and primary amines was heated on the solid surface of SSA under solvent-free conditions, the pyrrole-fused isocoumarins were formed in good yields. This synthetic method has several advantages such as the employment of solvent-free reaction conditions without the use of any toxic reagents and metal catalysts, the ease of product isolation, the use of a recyclable catalyst, the low cost, the easy availability of the starting materials, and the excellent yields of products.

scholarly journals Efficient N-formylation of primary aromatic amines using novel solid acid magnetic nanocatalyst

RSC Advances ◽  
2020 ◽  
Vol 10 (67) ◽  
pp. 41229-41236
Author(s):  
Jitendra Kumar Yadav ◽  
Priyanka Yadav ◽  
Satish K. Awasthi ◽  
Alka Agarwal
Keyword(s):  
Magnetic Nanoparticles ◽  
Aromatic Amines ◽  
Sulfonic Acid ◽  
Solid Acid ◽  
Recyclable Catalyst ◽  
Primary Amines ◽  
Magnetic Nanocatalyst ◽  
Reaction Conditions ◽  
Primary Aromatic Amines ◽  
First Time

Sulfonic acid functionalized over biguanidine fabricated silica-coated heterogeneous magnetic nanoparticles (NP@SO3H) have been synthesized, well characterized and explored for the first time, as an efficient and recyclable catalyst for N-formylation of primary amines under mild reaction conditions.

Synthesis of Novel 2-Alkoxy-5H-benzo[6,7]cyclohepta[1,2-b]pyridine-3-carbonitriles

2003 ◽  
Vol 58 (7) ◽  
pp. 698-703 ◽  
Author(s):  
Adel S. Girgis ◽  
I. S. Ahmed-Farag
Keyword(s):  
Single Crystal ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
X Ray ◽  
Independent Synthesis

Reaction of 6-arylmethylene-6,7,8,9-tetrahydro-5H-benzocyclo-hepten-5-ones (1) with malononitrile in the appropriate alcohol in the presence of sodium afforded the corresponding 2-alkoxy-4-aryl- 6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-b]pyridine-3-carbonitriles (2) and not their isomeric forms 2-alkoxy-4-aryl-6,7-dihydro-5H-benzo[3,4]-cyclohepta[1,2-c]pyridine-1-carbonitriles (3). The proposed structure was confirmed via independent synthesis of (2) through the reaction of 6,7,8,9- tetrahydro-5-benzocycloheptenone (4) with the appropriate ylidenemalononitriles 5 under the same reaction conditions. Single crystal X-ray diffraction proves the structures of 2a,b.

scholarly journals Manganese-mediated reductive functionalization of activated aliphatic acids and primary amines

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhan Li ◽  
Ke-Feng Wang ◽  
Xin Zhao ◽  
Huihui Ti ◽  
Xu-Ge Liu ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Late Stage ◽  
Materials Science ◽  
Reaction Pathway ◽  
Chemical Conversion ◽  
Primary Amines ◽  
Mechanistic Studies ◽  
Reaction Conditions ◽  
Aliphatic Acids ◽  
Redox Active

Abstract Alkyl carboxylic acids as well as primary amines are ubiquitous in all facets of biological science, pharmaceutical science, chemical science and materials science. By chemical conversion to redox-active esters (RAE) and Katritzky’s N-alkylpyridinium salts, respectively, alkyl carboxylic acids and primary amines serve as ideal starting materials to forge new connections. In this work, a Mn-mediated reductive decarboxylative/deaminative functionalization of activated aliphatic acids and primary amines is disclosed. A series of C-X (X = S, Se, Te, H, P) and C-C bonds are efficiently constructed under simple and mild reaction conditions. The protocol is applicable to the late-stage modification of some structurally complex natural products or drugs. Preliminary mechanistic studies suggest the involvement of radicals in the reaction pathway.

scholarly journals Efficient synthesis of pyrazolopyridines containing a chromane backbone through domino reaction

2019 ◽  
Vol 15 ◽  
pp. 874-880
Author(s):  
Razieh Navari ◽  
Saeed Balalaie ◽  
Saber Mehrparvar ◽  
Fatemeh Darvish ◽  
Frank Rominger ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Selectivity ◽  
Domino Reaction ◽  
Primary Amines ◽  
Efficient Synthesis ◽  
Atom Economy ◽  
Reaction Conditions ◽  
Efficient Approach ◽  
Three Component Reaction ◽  
High Yields

An efficient approach for the synthesis of pyrazolopyridines containing the aminochromane motif through a base-catalyzed cyclization reaction is reported. The synthesis was carried out through a three-component reaction of (arylhydrazono)methyl-4H-chromen-4-one, malononitrile, primary amines in the presence of Et3N at room temperature. However, carrying out the reaction under the same conditions without base led to a fused chromanyl-cyanopyridine. High selectivity, high atom economy, and good to high yields in addition to mild reaction conditions are the advantages of this approach.

Synthesis, Characterization and Performance of Superplasticizer with a Multi-Arm Structure

2015 ◽  
Vol 815 ◽  
pp. 594-600 ◽  
Author(s):  
Xiao Liu ◽  
Zi Ming Wang ◽  
Jie Zhu ◽  
Ming Zhao ◽  
Yun Sheng Zheng
Keyword(s):  
Acrylic Acid ◽  
The Self ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Reaction Products ◽  
Reaction Conditions ◽  
H Nmr ◽  
Polyhydric Alcohols ◽  
Esterification Rate ◽  
And Performance

A novel superplasticizer with a multi-arm structure, i.e., a “core” connected with multiple copolymer “arms”, was synthesized through two steps including an esterification reaction between polyhydric alcohols and acrylic acid and a copolymerization reaction in an aqueous solution among the esterification product, isobutenyl polyethylene glycol and acrylic acid. The reaction conditions were determined, and the results showed that the esterification rate can reach above 95% with a water-carrying agent of 70g, a catalyst/alcohol molar ratio of 0.07, an inhibitor/monomer molar ratio of 0.03, and a reaction time of 7 hrs. The reaction products were characterized by 1H Nuclear Magnetic Resonance (1H NMR) and Fourier Transform infrared spectroscopy (FTIR). It is confirmed to be the multi-arm structure, and the self-synthesized superplasticizer with a multi-arm structure exhibited higher energy efficiency, which was in accordance with its excellent paste fluidity performances and adsorption behavior in cement paste

scholarly journals Study on the Preparation and Application of Lignin-Derived Polycarboxylic Acids

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Ruiqi Wang ◽  
Bing Zhou ◽  
Zichen Wang
Keyword(s):  
Mechanical Properties ◽  
Main Product ◽  
Waterborne Polyurethane ◽  
Reaction Conditions ◽  
Polyurethane Elastomers ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Polycarboxylic Acids ◽  
Benzene Rings ◽  
Ft Ir

Lignin was oxidized by NaOCl, and the main product of the reaction was named lignin-derived polycarboxylic acids (LPCAs). The effect of the reaction conditions was studied. With the mix ratio [n(NaOCl)/m(lignin)] increasing, the content of carboxyl of LPCAs increased. When the reaction temperature or the reaction time increased, the content of carboxyl decreased in different degrees. After the oxidation by NaOCl, the content of hydroxyl and methoxyl of lignin decreased, and the molecular weight of lignin decreased as well. The FT-IR and 1H-NMR spectrum of lignin suggested that the benzene rings of lignin were disrupted after the oxidation. A possible mechanism of the oxidation of lignin by sodium hypochlorite is supposed to briefly demonstrate the reason that the benzene rings were disrupted and the content of carboxyl increased. Finally, an application example shows that LPCAs can strengthen the mechanical properties of waterborne polyurethane elastomers.

Metal-Free Oxidative C(sp3)–N Coupling by HBr and DMSO: A Novel Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones

Synlett ◽  
2018 ◽  
Vol 29 (07) ◽  
pp. 912-917 ◽  
Author(s):  
Parviz Ranjbar ◽  
Narjes Rezaei ◽  
Ehsan Sheikhi
Keyword(s):  
Oxidative Cyclization ◽  
Cyclization Reaction ◽  
Primary Amines ◽  
Isatoic Anhydride ◽  
Reaction Conditions ◽  
Coupling Process ◽  
Benzylic Alcohols ◽  
Metal Free ◽  
Novel Synthesis

A metal-free oxidative C(sp3)–N coupling process has been developed for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones. The reaction between primary amines, isatoic anhydride, and benzylic alcohols in the presence of HBr in DMSO at 80 °C affords 2,3-dihydroquinazolin-4(1H)-ones in excellent yields. Under these reaction conditions, benzylic alcohols react with in situ generated bromodimethylsulfonium bromide to form alkoxysulfonium intermediates. These intermediates undergo an oxidative cyclization reaction with primary amines and isatoic anhydride to produce the title products.

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