scholarly journals Synthesis of some mono and dialkynyl derivatives containing thieno[3,2-b]thiophene ring via Sonogashira alkynylation reaction

2019 ◽  
Vol 14 (9) ◽  
pp. 85
Author(s):  
Nguyen Hien ◽  
Duong Quoc Hoan
Keyword(s):  
Spectral Analysis ◽  
13C Nmr ◽  
Thiophene Ring ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Mass Spectral Analysis ◽  
1H And 13C Nmr ◽  
Mass Spectral ◽  
Cross Coupling Reactions ◽  
Moderate Yield

The Sonogashira cross-coupling reactions were used to synthesize 5 new monoalkynyl derivatives (10a-e) and 2 dialkynyl derivatives (12a-b) containing thieno[3,2-b]thiophene from monoaryl thieno[3,2-b]thiophen in moderate yield. The procedure was optimized and triphenylphosphine (0.2 eq.), palladium diacetate (0.1 eq), copper (I) iodide (0.2 eq.), THF, iPr2NH were found to be the best in these cases. The structures of the (10a-e) and (12a-b) compounds were elucidated by 1H and 13C NMR and mass spectral analysis.

Increments for 1H and 13C NMR chemical shifts in pinacol arylboronates

2012 ◽  
Vol 90 (1) ◽  
pp. 71-74
Author(s):  
Di Qiu ◽  
Zhitong Zheng ◽  
Fanyang Mo ◽  
Yan Zhang ◽  
Jianbo Wang
Keyword(s):  
Benzene Ring ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
1H And 13C Nmr ◽  
Nmr Chemical Shifts ◽  
Cross Coupling Reactions ◽  
C Nmr

Arylboronates are important compounds widely used in cross-coupling reactions. By analyzing the NMR spectra data of a variety of pinacol arylboronates, we have determined the increments for 1H and 13C NMR chemical shifts caused by a pinacol boronate substituent in the benzene ring. These data can be used in the estimation of chemical shifts of aromatic pinacol boronates.

1,2,4-triazoles Clubbed Pyrimidine Compounds with Synthesis, Antimicrobial, Antituberculosis, Antimalarial, and Anti-protozoal Studies

2020 ◽  
Vol 17 ◽  
Author(s):  
Navin B. Patel ◽  
Hetal I. Soni ◽  
Rahul B. Parmar ◽  
Manuel J. Chan-Bacab ◽  
Gildardo Rivera
Keyword(s):  
Spectral Analysis ◽  
1H Nmr ◽  
13C Nmr ◽  
Antifungal Agent ◽  
New Products ◽  
Antifungal Drugs ◽  
Bioactive Molecules ◽  
Mass Spectral Analysis ◽  
Mass Spectral

: Triazoles are famous as an antifungal agent. Itraconazole and fluconazole are the best examples of antifungal drugs available in the market, which consist an active triazole moiety. Pyrimidines are also bioactive molecules which shows multiple bioactivity. It’s an effort to synthesize pyrimidine clubbed triazole to enhance bioactivity. To synthesize new active pyrimidine clubbed triazole biomolecule and to evaluate these new products for better drug potential as antimicrobial, an-tituberculosis, antimalarial, and anti-protozoal. N-[4-(substituted phenyl)-6-(substituted aryl) pyrimidine-2-yl]-2-[(4H-1,2,4-triazol-4-yl)amino]acetamide(3A-J) were synthesized by different method as cyclization, condensation, purification and crystallization. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral analysis and screened for antibacterial, antifungal, anti-tuberculosis, antimalarial, and anti-protozoal activities. These com-pounds satisfied the bioactive response and simple way for the synthesis.

scholarly journals Proof for the biosynthetic conversion of L-(indole-15N)tryptophan to (10-15N)anthramycin using (13C,15N) labelling in conjunction with 13C-NMR and mass spectral analysis.

1980 ◽  
Vol 33 (10) ◽  
pp. 1167-1171 ◽  
Author(s):  
JOHN M. OSTRANDER ◽  
LAURENCE H. HURLEY ◽  
A. GAVIN MCINNES ◽  
DONALD G. SMITH ◽  
JOHN A. WALTER ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
13C Nmr ◽  
Mass Spectral Analysis ◽  
15N Labelling ◽  
Mass Spectral

scholarly journals 3-(3,5-Difluorophenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde

2018 ◽  
Author(s):  
Naveen Kumar ◽  
Swamy Sreenivasa ◽  
Vasantha Kumar ◽  
Nadigar Revansiddappa Mohan
Keyword(s):  
Spectral Analysis ◽  
13C Nmr ◽  
Title Compound ◽  
Structure Characterization ◽  
Dimethyl Formamide ◽  
The Novel ◽  
Mass Spectral Analysis ◽  
Mass Spectral ◽  
Phosphorous Oxychloride

Vilsmeier–Haack reaction of (E)-1-(1-(3,5-difluorophenyl)ethylidene)-2-phenylhydrazine (1) using dimethyl formamide in excess of phosphorous oxychloride by conventional method, resulted in the synthesis of title compound 3-(3,5-difluorophenyl)-1-phenyl-1H-pyrazole-4- carbaldehyde (2) in good yield and high purity. Structure characterization of the novel title compound was done by IR, 1H NMR, 13C NMR and mass spectral analysis.

Dual Nickel/Palladium-Catalyzed Reductive Cross-Coupling Reactions Between Two Phenol Derivatives

2020 ◽  
Author(s):  
Baojian Xiong ◽  
Yue Li ◽  
Yin Wei ◽  
Søren Kramer ◽  
Zhong Lian
Keyword(s):  
Functional Group ◽  
Low Cost ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Phenol Derivatives ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
One Step ◽  
Aryl Tosylates ◽  
Low Sensitivity

Cross-coupling between substrates that can be easily derived from phenols is highly attractive due to the abundance and low cost of phenols. Here, we report a dual nickel/palladium-catalyzed reductive cross-coupling between aryl tosylates and aryl triflates; both substrates can be accessed in just one step from readily available phenols. The reaction has a broad functional group tolerance and substrate scope (>60 examples). Furthermore, it displays low sensitivity to steric effects demonstrated by the synthesis of a 2,2’disubstituted biaryl and a fully substituted aryl product. The widespread presence of phenols in natural products and pharmaceuticals allow for straightforward late-stage functionalization, illustrated with examples such as Ezetimibe and tyrosine. NMR spectroscopy and DFT calculations indicate that the nickel catalyst is responsible for activating the aryl triflate, while the palladium catalyst preferentially reacts with the aryl tosylate.

An Iron-Based Catalyst Enables The Enantioconvergent Synthesis of Chiral 1,1-Diarylalkanes Through a Suzuki-Miyaura Cross-Coupling Reaction

2020 ◽  
Author(s):  
Chet Tyrol ◽  
Nang Yone ◽  
Connor Gallin ◽  
Jeffery Byers
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Radical Intermediates ◽  
Cross Coupling Reactions ◽  
Cross Coupling Reaction ◽  
Boronic Esters ◽  
Carbon Centered Radical ◽  
Iron Based ◽  
High Yields

By using an iron-based catalyst, access to enantioenriched 1,1-diarylakanes was enabled through an enantioselective Suzuki-Miyaura crosscoupling reaction. The combination of a chiral cyanobis(oxazoline) ligand framework and 1,3,5-trimethoxybenzene additive were essential to afford high yields and enantioselectivities in cross-coupling reactions between unactivated aryl boronic esters and a variety of benzylic chlorides, including challenging ortho-substituted benzylic chloride substrates. Mechanistic investigations implicate a stereoconvergent pathway involving carbon-centered radical intermediates.

Phosphino-Triazole Ligands for Palladium-Catalysed Cross-Coupling

2018 ◽  
Author(s):  
Yiming Zhao ◽  
Huy van Nguyen ◽  
Louise Male ◽  
Philip Craven ◽  
Benjamin R. Buckley ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Cross Coupling ◽  
Product Formation ◽  
Coupling Reactions ◽  
Volume Determination ◽  
Online Tool ◽  
Triazole Derivatives ◽  
Cross Coupling Reactions ◽  
Modelling Approaches

<div>Twelve 1,5-disubtituted and fourteen 5-substituted 1,2,3-triazole derivatives bearing diaryl or dialkyl phosphines at the 5-position were synthesised and used as ligands for palladium-catalysed Suzuki-Miyaura cross-coupling reactions. Bulky substrates were tested, and lead-like product formation was demonstrated. The online tool SambVca 2.0 was used to assess steric parameters of ligands and preliminary buried volume determination using XRD obtained data in a small number of cases proved to be informative. Two modelling approaches were compared for the determination of</div><div>the buried volume of ligands where XRD data was not available. An approach with imposed steric restrictions was found to be superior in leading to buried volume determinations that closely correlate with observed reaction conversions. The online tool LLAMA was used to determine lead-likeness of potential Suzuki-Miyaura cross-coupling products, from which ten of the most lead-like were successfully synthesised. Thus, confirming these readily accessible triazole-containing phosphines as highly suitable ligands for reaction screening and optimisation in drug discovery campaigns.</div>

A Revised Modular Approach to D8-THC and Derivatives Through Late-Stage Suzuki-Miyaura Cross-Coupling Reactions

2019 ◽  
Author(s):  
Victor Bloemendal ◽  
Floris P. J. T. Rutjes ◽  
Thomas J. Boltje ◽  
Daan Sondag ◽  
Hidde Elferink ◽  
...  
Keyword(s):  
Biological Activity ◽  
Late Stage ◽  
Medicinal Chemistry ◽  
Cross Coupling ◽  
Modular Approach ◽  
Coupling Reactions ◽  
One Pot ◽  
Biologically Relevant ◽  
Cross Coupling Reactions ◽  
Chemistry Research

<p>In this manuscript we describe a modular pathway to synthesize biologically relevant (–)-<i>trans</i>-Δ<sup>8</sup>-THC derivatives, which can be used to modulate the pharmacologically important CB<sub>1</sub> and CB<sub>2</sub> receptors. This pathway involves a one-pot Friedel-Crafts alkylation/cyclization protocol, followed by Suzuki-Miyaura cross-coupling reactions and gives rise to a series of new Δ<sup>8</sup>-THC derivatives. In addition, we demonstrate using extensive NMR evidence that similar halide-substituted Friedel-Crafts alkylation/cyclization products in previous articles were wrongly assigned as the para-isomers, which also has consequence for the assignment of the subsequent cross-coupled products and interpretation of their biological activity. </p> <p>Considering the importance of the availability of THC derivatives in medicinal chemistry research and the fact that previously synthesized compounds were wrongly assigned, we feel this research is describing a straightforward pathway into new cannabinoids.</p>

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