scholarly journals Thiol–ene coupling reaction achievement and monitoring by “in situ” UV irradiation NMR spectroscopy

RSC Advances ◽  
2020 ◽  
Vol 10 (42) ◽  
pp. 25214-25222
Author(s):  
Natalia Toncheva-Moncheva ◽  
Miroslav Dangalov ◽  
Nikolay G. Vassilev ◽  
Christo P. Novakov
Keyword(s):  
Nmr Spectroscopy ◽  
Uv Irradiation ◽  
Glycidyl Ether ◽  
Coupling Reaction ◽  
Polyethylene Glycols ◽  
Coupling Reactions ◽  
Uv Illumination ◽  
Allyl Glycidyl Ether

An “In situ” LED UV illumination NMR setup for achievement of initiator-free coupling reactions of allyl-functionalized poly(allyl glycidyl ether) with polyethylene glycols thiols.

scholarly journals Efficient in situ N-heterocyclic carbene palladium(ii) generated from Pd(OAc)2 catalysts for carbonylative Suzuki coupling reactions of arylboronic acids with 2-bromopyridine under inert conditions leading to unsymmetrical arylpyridine ketones: synthesis, characterization and cytotoxic activities

RSC Advances ◽  
2018 ◽  
Vol 8 (70) ◽  
pp. 40000-40015 ◽  
Author(s):  
Nedra Touj ◽  
Abdullah S. Al-Ayed ◽  
Mathieu Sauthier ◽  
Lamjed Mansour ◽  
Abdel Halim Harrath ◽  
...  
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Suzuki Coupling ◽  
Boronic Acids ◽  
Cytotoxic Activities ◽  
Coupling Reactions ◽  
Component System ◽  
Arylboronic Acids ◽  
Cross Coupling Reaction

The in situ prepared four component system Pd(OAc)2, 1,3-dialkylbenzimidazolium halides 2a–i and 4a–i, K2CO3 under CO atmosphere catalyses carbonylative cross-coupling reaction of 2-bromopyridine with various boronic acids to yield unsymmetrical arylpyridine ketones.

An easily prepared palladium-hydrogel nanocomposite catalyst for C–C coupling reactions

2014 ◽  
Vol 2 (44) ◽  
pp. 18952-18958 ◽  
Author(s):  
Mitasree Maity ◽  
Uday Maitra
Keyword(s):  
Palladium Nanoparticles ◽  
Room Temperature ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Sodium Cyanoborohydride ◽  
Efficient Catalyst ◽  
Suzuki Coupling Reaction ◽  
Reaction In Water ◽  
Hydrogel Nanocomposite

Palladium nanoparticles were efficiently prepared in situ by sodium cyanoborohydride reduction of Pd(ii) at room temperature using calcium-cholate hydrogel fibers as templates. The PdNPs self-organize on the gel fibers, which supports the controlled growth as well as stabilization of PdNPs. The hybrid xerogel was used as an efficient catalyst for the Suzuki coupling reaction in water.

scholarly journals Enantioselective Iron/Bisquinolyldiamine Ligand-Catalyzed Oxidative Coupling Reaction of 2-Naphthols

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 852 ◽  
Author(s):  
Lin-Yang Wu ◽  
Muhammad Usman ◽  
Wen-Bo Liu
Keyword(s):  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Iron Complex ◽  
Coupling Reactions ◽  
Oxidative Coupling Reaction ◽  
Oxidative Coupling Reactions

An iron-catalyzed asymmetric oxidative homo-coupling of 2-naphthols for the synthesis of 1,1′-Bi-2-naphthol (BINOL) derivatives is reported. The coupling reaction provides enantioenriched BINOLs in good yields (up to 99%) and moderate enantioselectivities (up to 81:19 er) using an iron-complex generated in situ from Fe(ClO4)2 and a bisquinolyldiamine ligand [(1R,2R)-N1,N2-di(quinolin-8-yl)cyclohexane-1,2-diamine, L1]. A number of ligands (L2–L8) and the analogs of L1, with various substituents and chiral backbones, were synthesized and examined in the oxidative coupling reactions.

scholarly journals Palladium-catalyzed Suzuki-Miyaura coupling of thioureas or thioamides

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Shaoyu Mai ◽  
Wendong Li ◽  
Xue Li ◽  
Yingwei Zhao ◽  
Qiuling Song
Keyword(s):  
Silver Salt ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Mechanistic Studies ◽  
Aromatic Rings ◽  
Cross Coupling Reactions ◽  
Broad Array ◽  
Palladium Catalyzed

AbstractCross-coupling reactions involving metal carbene intermediates play an increasingly important role in C–C bond formation. Expanding the carbene precursors to a broader range of starting materials and more diverse products is an ongoing challenge in synthetic organic chemistry. Herein, we report a Suzuki-Miyaura coupling reaction of in situ-generated Pd–carbene complexes via desulfurization of thioureas or thioamides. This strategy enables the preparation of a broad array of substituted amidinium salts and unsymmetrical diaryl ketones. The reaction is readily scalable, compatible with bromo groups on aromatic rings, tolerant to moisture and air and has a broad substrate scope. Furthermore, a single crystal structure of Pd-diaminocarbene complex is obtained and proven to be the key intermediate in both catalytic and stoichiometric reactions. Preliminary mechanistic studies demonstrate the dual role of the silver salt as a desulfurating reagent assisting the elimination of sulfur and as oxidant facilitating the PdII/Pd0/PdII catalytic cycle.

In Situ Coloration of Silk with Coupling Reaction and the Spectrum Characteristics

2013 ◽  
Vol 796 ◽  
pp. 428-431
Author(s):  
Wei Guo Chen ◽  
Zong Qian Wang ◽  
Zhi Hua Cui ◽  
Zhao Cheng Meng
Keyword(s):  
Silk Fibroin ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Tyrosine Residue ◽  
Fastness Properties ◽  
Silk Industry ◽  
Tyrosine Residues ◽  
Spectrum Characteristics ◽  
Dyeing Method

High wet fastness dyeing is always the hot issue of silk industry. The plenty of tyrosine residue in silk protein may contribute an opportunity to solve this problem. In this paper, in situ coloration of silk is described using coupling reaction between diazonium compounds, made from different arylamine derivatives, and tyrosine residues in the silk fibroin. The spectra of coloured silk and the washing and rubbing fastness were measured. The results suggest that the use of coupling reactions could be developed into a dyeing method for silk. The wet fastness properties of such coloration are good because the chromophores are incorporated into the protein chains.

scholarly journals The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

2016 ◽  
Vol 12 ◽  
pp. 1987-2004 ◽  
Author(s):  
Faith M Akwi ◽  
Paul Watts
Keyword(s):  
Continuous Flow ◽  
Coupling Reaction ◽  
Azo Compounds ◽  
Coupling Reactions ◽  
Azo Coupling ◽  
Reaction Conditions ◽  
Flow Rates ◽  
Flow Synthesis ◽  
Optimum Flow

In this paper, a micro-fluidic optimized process for the continuous flow synthesis of azo compounds is presented. The continuous flow synthesis of Sudan II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98% was achieved in approximately 2.4 minutes and a small library of azo compounds was thus generated under these reaction conditions from couplers with aminated or hydroxylated aromatic systems. The scaled up synthesis of these compounds in PTFE tubing (i.d. 1.5 mm) was also investigated, where good reaction conversions ranging between 66–91% were attained.

Synthesis of a Contrapositionally Substituted Cyclohexa-meta-phenylene: A Ready-to-Use Precursor for Cyclohexa-meta-phenylene-Based Materials

Synlett ◽  
2019 ◽  
Vol 30 (16) ◽  
pp. 1886-1890
Author(s):  
Ifzan Arshad ◽  
Aamer Saeed ◽  
Pervaiz Ali Channar ◽  
Syeda Aaliya Shehzadi ◽  
Rana Muhammad Irfan
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Coupling Reaction ◽  
Suzuki Coupling ◽  
Coupling Reactions ◽  
Iodine Monochloride ◽  
Synthetic Route ◽  
Metal Catalyzed ◽  
Yamamoto Coupling ◽  
Trimethylsilyl Groups

A contrapositionally substituted derivative of cyclohexa-meta-phenylene ([6]CMP) was synthesized by an intramolecular Yamamoto coupling reaction of an appropriate terphenyl unit containing a trimethylsilyl substituent. Iododesilylation of the trimethylsilyl groups of the product with iodine monochloride was used to incorporate iodo groups, an important functionality for metal-catalyzed coupling reactions. The iodo groups were also converted into a (pinacolato)boryl groups, another important functionality for coupling reactions. The diborylated [6]CMP is expected to be a versatile potential comonomer and a precursor for the synthesis of CMP-based materials. The synthetic route to the disubstituted [6]CMP included lithiation, Pd-catalyzed borylation, Suzuki coupling, and Yamamoto coupling. The structure of the product was established by NMR spectroscopy and mass spectrometry.

Highly conductive air-stable ZnO thin film formation under in situ UV illumination for an indium-free transparent electrode

RSC Advances ◽  
2016 ◽  
Vol 6 (73) ◽  
pp. 69027-69032 ◽  
Author(s):  
Boram Cho ◽  
Hongbum Kim ◽  
Dasom Yang ◽  
Nabeen K. Shrestha ◽  
Myung Mo Sung
Keyword(s):  
Thin Film ◽  
Uv Irradiation ◽  
Oxygen Vacancies ◽  
Film Formation ◽  
Transparent Electrode ◽  
Zno Thin Film ◽  
Zno Film ◽  
Uv Illumination ◽  
Thin Film Formation

In situ UV irradiation during ALD cycles generates oxygen-vacancies, partially removes O–H bonds, and thereby produces a highly transparent and highly conductive air-stable ZnO film.

Formation of methyl 2-arylhydrazono-3-oxobutanoates and 2-arylhydrazono-3-oxobutanenitriles during the coupling reaction of arenediazonium ions with methyl 3-aminocrotonate and 3-aminocrotononitrile

1995 ◽  
Vol 73 (2) ◽  
pp. 169-175 ◽  
Author(s):  
D. Sean Brown ◽  
Jason V. Jollimore ◽  
Marcus P. Merrin ◽  
Keith Vaughan ◽  
Donald L. Hooper
Keyword(s):  
Mass Spectrometry ◽  
Hydrogen Bonding ◽  
Nmr Spectroscopy ◽  
Nmr Spectra ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Diazonium Coupling ◽  
High Yields ◽  
Hydrolysis Of ◽  
C Nmr

Reaction of aryldiazonium salts with methyl 3-aminocrotonate (1) affords high yields of the methyl 2-arylhydrazono-3-oxobutanoates (4); analogous diazonium coupling with 3-aminocrotononitrile (2) gives the 2-arylhydrazono-3-oxobutanenitriles (5). The hydrazones are the product of diazonium coupling at the C2-vinylic carbon, concomitant with hydrolysis of the 3-amino substituent to the 3-oxo derivative; there is no evidence for the formation of a triazene (6), which would be the product of N-coupling. All hydrazones (4a–e and 5a–d) have been fully characterized by IR and 1H and 13C NMR spectroscopy; the NMR spectra of the methyl 2-arylhydrazono-3-oxobutanoates (4) suggest the presence of two isomeric intramolecularly H-bonded forms in solution. Selected compounds were further characterized by elemental analysis and mass spectrometry. A mechanism is proposed for the conversion of 1 or 2 into 4 or 5, and these observations are compared with previously reported observations of diazonium coupling reactions with unsaturated systems. Keywords: hydrazone, diazonium, aminocrotonate, aminocrotononitrile, hydrogen bonding.

Sign in / Sign up

Export Citation Format

Share Document