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   Org. Lett. 2017, 19, 4960-4963
Fluoroalkyl Amino Reagents for the Introduction of the Fluoro(trifluoromethoxy)methyl Group onto Arenes and Heterocycles
E. Schmitt, S. Bouvet, B. Pégot, A. Panossian, J.-P. Vors, S. Pazenok, E. Magnier, F. R. Leroux

FARs have been developed from commercially available trifluoromethyl trifluorovinyl ether via a hydroamination reaction with diethylamine or dimethylamine. These reagents can be activated by treatment with a Lewis acid and subsequently used as a mono- or dielectrophile for the introduction of the fluoro(trifluoromethoxy)methyl group, either in Vilsmeier-type acylations of aromatic substrates or in the synthesis of fluorinated pyrazoles from CH-acidic substrates and of bis-fluorinated pyrazoles, all being important building blocks for medicinal and agricultural chemistry.

   J. Fluorine Chem. 2017, 203, 155-163
Tri- and difluoromethoxylated N-based heterocycles − Synthesis and insecticidal activity of novel F3CO- and F2HCO-analogues of Imidacloprid and Thiacloprid
G. Landelle, E. Schmitt, A. Panossian, J.-P. Vors, S. Pazenok, P. Jeschke, O. Gutbrod, F. R. Leroux

The preparation of F3CO- and F2HCO-analogues of Imidacloprid and Thiacloprid and the evaluation of their biological activity have been performed. The broad diversity of compatible heterocycles includes a large series of substituted hydroxy-pyridines, but also −pyrazoles, −pyrazine, −pyridazine, and −quinolines. This work enables the preparation of valuable building blocks, which could lead to the discovery of new bioactive entities.

   J. Org. Chem. 2017, 82, 11877–11883

Asymmetric α-Sulfonyl- and α-Phosphoryl-Oxylation of Ketones by a Chiral Hypervalent Iodine(III)

G. Levitre, A. Dumoulin, P. Retailleau, A. Panossian, F. R. Leroux, G. Masson

An enantioselective direct oxygenation of propiophenone derivatives mediated by a catalytic or stoichiometric amount of new chiral non-C2-symmetric iodoarenes(III) is reported. The reaction gives an easy entry to optically active α-sulfonyl- and α-phosphoryl oxyketones in respectable yields and enantioselectivities.

   J. Org. Chem. 2017, 82, 6629–6637
Switchable Diastereoselectivity in the Fluoride-Promoted Vinylogous Mukaiyama–Michael Reaction of 2-[(Trimethylsilyl)oxy]furan Catalyzed by Crown Ethers

G. Della Sala, M. Sicignano, R. Schettini, F. De Riccardis, L. Cavallo, Y. Minenkov, C. Batisse, G. Hanquet, F. R. Leroux, I. Izzo

The F--promoted VMMR of 2-TMSO-furan with α,β-unsaturated ketones is described. TBAF-catalyzed VMMR gave high anti-d.r.. The KF/crown ethers catalytic systems resulted in a highly d.r. solvent/catalyst switchable reaction. Anti-adducts were obtained as single diastereomers or with excellent d.r. when benzo-15-crown-5 in DCM was employed. High syn-d.r. were achieved by employing dicyclohexane-18-crown-6 in toluene. By DFT calculations, the catalysts/solvent-dependent switchable selectivities are proposed to result from loose or tight cation-dienolate ion pairs.

   Molecules 2017, 22, 977

Fluoroalkyl Amino Reagents (FARs): A General Approach towards the Synthesis of Heterocyclic Compounds Bearing Emergent Fluorinated Substituents

B. Commare, E. Schmitt, F. Aribi, A. Panossian, J.-P. Vors, S. Pazenok, F. R. Leroux

Fluorinated heterocycles are important building blocks in pharmaceutical, agrochemical and material sciences. Therefore, organofluorine chemistry has witnessed high interest in the development of efficient methods for the introduction of emergent fluorinated substituents (EFS) onto heterocycles. In this context, fluoroalkyl amino reagents (FARs)-a class of chemicals that was slightly forgotten over the last decades-has emerged again recently and proved to be a powerful tool for the introduction of various fluorinated groups onto (hetero)aromatic derivatives.

   C. R. Chim. 2017, 20, 682-692

Control of axial chirality in absence of transition metals based on arynes

F. R. Leroux, A. Panossian, D. Augros

  Eur. J. Org. Chem. 2017, 3, 497-503
 Transition-Metal-Free Synthesis of a Known Intermediate in the Formal Synthesis of (–)-Steganacin

D. Augros, B. Yalcouye, S. Choppin, M. Chessé, A. Panossian, F. R. Leroux

The formal synthesis of the two enantiomers of a natural, axially chiral biaryl, steganacin, is reported. In each step, the axial configuration of the biaryl could be maintained. The key intermediate, identified previously, was accessed without using transition metals, which demonstrates the potential of the aryne coupling reaction as a complementary or alternative to transition-metal-catalyzed coupling reactions.

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