application-elemental-lanthanides-selective-c-f-activation

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

The selective activation of one carbon-fluorine bond in polyfluorinated aromatic molecules or in trifluoromethyl-containing substrates offers the ...

Université de Reims Champagne Ardenne

The synthesis of an optically pure proline-based tryptophan mimetic is described. The strategy involves the in situ generation of an unprecedented allylmetal species containing the indole moiety, and its coupling with a chiral imine. The construction of the 3-substituted proline skeleton is then achieved through a hydrozirconation/iodination sequence applied to the resulting homoallylic amine.

Asymmetric synthesis of proline-based conformationally constrained tryptophan mimetic.

The generation of cyclopent-2-enylzinc from cyclopentadiene based on a titanium-catalyzed hydroalumination/transmetallation sequence is described. Applied to the allylmetallation of phenylglycinol-derived imines, this sequence leads to homoallylic amines with moderate to good stereoselectivities. The synthesis of disubstituted azetidines and piperidines illustrates the potential of the method. 

Cyclopent-2-enylaluminium as allylzinc precursor for the diastereoselective allylmetallation of non-racemic imines: applications to the synthesis of enantiomerically enriched heterocycles.

An efficient (+)-camphor-mediated kinetic resolution of racemic cyclohex-2-en-1-ylalane is described. This approach provides an enantiomerically enriched form of the alane, in situ available for synthetic uses. Applied to the allylation of aldehydes, this protocol leads to the corresponding homoallylalcohols in a highly enantioselective manner.

(+)-Camphor-mediated kinetic resolution of allylalanes: a strategy towards enantio-enriched cyclohex-2-en-1-ylalane.

Heavy metal on Lewis acid: The combination of lanthanide metals and AlCl has been employed for selective single C-F activation in benzofulvenes comprising an exocyclic CF substituent. Intermediate ϵ,ϵ-difluorinated metal-dienyl species react with a large variety of aldehydes in a highly regio- and diastereoselective fashion to afford 1,1-disubstituted indenes bearing a difluorovinyl group. These new building blocks have been further transformed through a hydrogenation-cyclization process into fluorinated heterocyclic spiro compounds.

Generation of ϵ,ϵ-Difluorinated Metal-Pentadienyl Species through Lanthanide-Mediated C-F Activation.

Synthetic analogues of the naturally occurring iminosugar homoDMDP, which feature a perfluoroalkyl group at the pseudo-anomeric position, have been synthesized from the corresponding sugar-derived cyclic aldonitrone. The new fluorinated iminosugars as well as homoDMDP and its 6-deoxy counterpart were evaluated for their inhibitory activity against a panel of glycosidases. While the replacement of the (1',2')-dihydroxyethyl substituent of homoDMDP with -CF proved detrimental for enzyme binding, introduction of a -CF moiety tuned the inhibitory activity spectrum selectively towards α-fucosidase and α-glucosidase from yeast.

Jean-Luc Vasse

Institut de Chimie Moléculaire de Reims UMR 7312

Université de Reims Champagne Ardenne

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Jean-Luc Vasse

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institut de Chimie Moléculaire de Reims UMR 7312

Université de Reims Champagne Ardenne

Application of Elemental Lanthanides in the Selective C-F Activation of Trifluoromethylated Benzofulvenes Providing Access to Various Difluoroalkenes

Institut de Chimie Moléculaire de Reims UMR 7312