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Kiev, Ukraine

Mykhailiuk P.K.,Enamine Ltd | Mykhailiuk P.K.,Taras Shevchenko National University
Organic and Biomolecular Chemistry | Year: 2015

Three-component reaction between RCF2CH2NH2·HCl, NaNO2 and electron-deficient alkynes significantly depends on substituent "R". The reaction gives the fluorinated pyrazoles in high yields when "R" is a fluorine atom or a fluoroalkyl group. With other "R" unexpected products are formed. This journal is © The Royal Society of Chemistry 2015. Source


Mykhailiuk P.K.,Taras Shevchenko National University | Mykhailiuk P.K.,Enamine Ltd
Chemistry - A European Journal | Year: 2014

The novel chemical reagent, C2F5CHN2, is generated in situ from C2F5CH2NH 2̇HCl and sodium nitrite. It reacts with mono- and disubstituted electron-deficient alkenes at room temperature to afford C2F 5-pyrazolines in excellent yields © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Mykhailiuk P.K.,Enamine Ltd | Mykhailiuk P.K.,Taras Shevchenko National University
Angewandte Chemie - International Edition | Year: 2015

A novel approach to agrochemically important difluoromethyl-substituted pyrazoles has been developed based on the elusive reagent CF2HCHN2, which was synthesized (generated in situ) for the first time and employed in [3+2] cycloaddition reactions with alkynes. The reaction is extremely practical as it is a one-pot process, does not require a catalyst or the isolation of the potentially toxic and explosive gaseous intermediate, and proceeds in a common solvent, namely chloroform, in air. The reaction is also scalable and allows for the preparation of the target pyrazoles on gram scale. A new reagent: The elusive chemical reagent CF2HCHN2 was generated in situ for the first time and further reacted with alkynes in a [3+2] cycloaddition reaction. This transformation constitutes a novel and efficient approach to agrochemically important difluoromethylated pyrazoles. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Mykhailiuk P.K.,Enamine Ltd | Mykhailiuk P.K.,Taras Shevchenko National University
Beilstein Journal of Organic Chemistry | Year: 2014

A one-pot reaction between C2F5CH2NH2•HCl, NaNO2 and electron-deficient alkynes gives C2F5 -substituted pyrazoles in excellent yields. The transformation smoothly proceeds in dichloromethane/water, tolerates the presence of air, and requires no purification of products by column chromatography. Mechanistically, C2F5CH2NH2 •HCl and NaNO2 react first in water to generate C2F5CHN2 , that participates in a [3 + 2] cycloaddition with electron-deficient alkynes in dichloromethane. © 2015 Mykhailiuk; licensee Beilstein-Institut. Source


Slobodyanyuk E.Y.,Taras Shevchenko National University | Artamonov O.S.,Ukrainian Academy of Sciences | Shishkin O.V.,Ukrainian Academy of Sciences | Mykhailiuk P.K.,Taras Shevchenko National University | Mykhailiuk P.K.,Enamine Ltd
European Journal of Organic Chemistry | Year: 2014

The [3+2] cycloaddition of CF3CHN2, generated in situ, with electron-deficient alkenes/alkynes affords CF3-substituted pyrazolines/pyrazoles in quantitative yields. The one-pot three-component reaction between CF3CH2NH2·HCl, NaNO2, and the substrate proceeds at room temperature in dichloromethane/water. Three-component reaction between CF3CH 2NH2·HCl, NaNO2 and electron-deficient alkenes/alkynes gives CF3-substituted pyrazolines/pyrazoles at room temperature in excellent yields. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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