Zinc-catalyzed regioselective C–P coupling of p-quinol ethers with secondary phosphine oxides to afford 2-phosphinylphenols

2019 ◽  
Vol 17 (11) ◽  
pp. 2972-2984 ◽  
Author(s):  
Ming Zhang ◽  
Xiaoyu Jia ◽  
Haowei Zhu ◽  
Xutong Fang ◽  
Chenyi Ji ◽  
...  
Keyword(s):  
Synthesis Method ◽  
Coupling Reaction ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
New Synthesis

A highly regioselective C–P coupling reaction of p-quinol ethers with secondary phosphine oxides is developed as a new synthesis method for 2-phosphinylphenols by using Zn(OTf)2 as the catalyst.

Ph3P-mediated highly selective C(α)–P coupling of quinone monoacetals with R2P(O)H: convenient and practical synthesis of ortho-phosphinyl phenols

2018 ◽  
Vol 20 (22) ◽  
pp. 5111-5116 ◽  
Author(s):  
Ruwei Shen ◽  
Ming Zhang ◽  
Jing Xiao ◽  
Chao Dong ◽  
Li-Biao Han
Keyword(s):  
Coupling Reaction ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
Practical Synthesis

The Ph3P-mediated C(α)–P coupling reaction of quinone monoacetals with secondary phosphine oxides is developed to provide an effective method for the synthesis of a wide array of ortho-phosphinyl phenols in good to excellent yields.

Synthesis, Analytical Characterization and Spectroscopic Investigation of Chloramphenicol Impurity A for the Quality Control of Chloramphenicol and its Formulation as Per International Compendium

2020 ◽  
Vol 17 (5) ◽  
pp. 382-388
Author(s):  
Aparna Wadhwa ◽  
Faraat Ali ◽  
Sana Parveen ◽  
Robin Kumar ◽  
Gyanendra N. Singh
Keyword(s):  
Quality Control ◽  
Synthesis Method ◽  
Analytical Techniques ◽  
International Markets ◽  
Therapeutic Effects ◽  
Reference Standard ◽  
Working Standard ◽  
Prior Art ◽  
New Synthesis ◽  
Synthetic Procedure

Objective: The main aim of the present work is to synthesize chloramphenicol impurity A (CLRMIMP- A) in the purest form and its subsequent characterization by using a panel of sophisticated analytical techniques (LC-MS, DSC, TGA, NMR, FTIR, HPLC, and CHNS) to provide as a reference standard mentioned in most of the international compendiums, including IP, BP, USP, and EP. The present synthetic procedure has not been disclosed anywhere in the prior art. Methods: A simple, cheaper, and new synthesis method was described for the preparation of CLRM-IMP-A. It was synthesized and characterized by FTIR, DSC, TGA, NMR (1H and 13C), LC-MS, CHNS, and HPLC. Results: CLRM-IMP-A present in drugs and dosage form can alter the therapeutic effects and adverse reaction of a drug considerably, it is mandatory to have a precise method for the estimation of impurities to safeguard the public health. Under these circumstances, the presence of CLRM-IMP-A in chloramphenicol (CLRM) requires strict quality control to satisfy the specified regulatory limit. The synthetic impurity obtained was in the pure form to provide a certified reference standard or working standard to stakeholders with defined potency. Conclusion: The present research describes a novel technique for the synthesis of pharmacopoeial impurity, which can help in checking/controlling the quality of the CLRM in the international markets.

scholarly journals Microwaves as “Co-Catalysts” or as Substitute for Catalysts in Organophosphorus Chemistry

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1196
Author(s):  
György Keglevich
Keyword(s):  
Coupling Reaction ◽  
Diels Alder ◽  
Typical Case ◽  
Conventional Heating ◽  
Phosphine Oxides ◽  
Phosphonic Acids ◽  
Co Catalysts ◽  
Mw Irradiation ◽  
Organophosphorus Chemistry ◽  
Hydrolysis Of

The purpose of this review is to summarize the importance of microwave (MW) irradiation as a kind of catalyst in organophosphorus chemistry. Slow or reluctant reactions, such as the Diels-Alder cycloaddition or an inverse-Wittig type reaction, may be performed efficiently under MW irradiation. The direct esterification of phosphinic and phosphonic acids, which is practically impossible on conventional heating, may be realized under MW conditions. Ionic liquid additives may promote further esterifications. The opposite reaction, the hydrolysis of P-esters, has also relevance among the MW-assisted transformations. A typical case is when the catalysts are substituted by MWs, which is exemplified by the reduction of phosphine oxides, and by the Kabachnik–Fields condensation affording α-aminophosphonic derivatives. Finally, the Hirao P–C coupling reaction may serve as an example, when the catalyst may be simplified under MW conditions. All of the examples discussed fulfill the expectations of green chemistry.

scholarly journals Green Synthesis of Copper Nanoparticles Using Cotton

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1906
Author(s):  
Marissa Pérez-Alvarez ◽  
Gregorio Cadenas-Pliego ◽  
Odilia Pérez-Camacho ◽  
Víctor E. Comparán-Padilla ◽  
Christian J. Cabello-Alvarado ◽  
...  
Keyword(s):  
Green Synthesis ◽  
Copper Nanoparticles ◽  
Uv Spectroscopy ◽  
Synthesis Method ◽  
Crystallinity Index ◽  
Reaction Conditions ◽  
New Synthesis ◽  
Water As Solvent ◽  
Characterization Studies ◽  
Xrd Patterns

Copper nanoparticles (CuNP) were obtained by a green synthesis method using cotton textile fibers and water as solvent, avoiding the use of toxic reducing agents. The new synthesis method is environmentally friendly, inexpensive, and can be implemented on a larger scale. This method showed the cellulose capacity as a reducing and stabilizing agent for synthetizing Cellulose–Copper nanoparticles (CCuNP). Nanocomposites based on CCuNP were characterized by XRD, TGA, FTIR and DSC. Functional groups present in the CCuNP were identified by FTIR analysis, and XRD patterns disclosed that nanoparticles correspond to pure metallic Cu°, and their sizes are at a range of 13–35 nm. Results demonstrated that CuNPs produced by the new method were homogeneously distributed on the entire surface of the textile fiber, obtaining CCuNP nanocomposites with different copper wt%. Thus, CuNPs obtained by this method are very stable to oxidation and can be stored for months. Characterization studies disclose that the cellulose crystallinity index (CI) is modified in relation to the reaction conditions, and its chemical structure is destroyed when nanocomposites with high copper contents are synthesized. The formation of CuO nanoparticles was confirmed as a by-product, through UV spectroscopy, in the absorbance range of 300–350 nm.

Thermal stability of primary and secondary phosphine oxides formed as a reaction of phosphine oxide with ketones

2016 ◽  
Vol 191 (11-12) ◽  
pp. 1480-1481 ◽  
Author(s):  
E. V. Gorbachuk ◽  
E. K. Badeeva ◽  
S. A. Katsyuba ◽  
P. O. Pavlov ◽  
Kh. R. Khayarov ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Phosphine Oxide ◽  
Secondary Phosphine ◽  
Phosphine Oxides ◽  
Thermal Stability Of
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