title: Highly enantioselective copper(I)-catalyzed conjugate addition of terminal alkynes to 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones: new ester/amide surrogates in asymmetric catalysis.
abstract: A highly enantioselective copper-catalyzed conjugate alkynylation of monoactivated enones, namely 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones, is described. The reaction products are obtained with good yields and excellent enantioselectivities (from 92 to 99% ee). The β-alkynylated difluoro(phenylsulfonyl) ketones can be converted into the corresponding β-alkynylated difluoro- and trifluoromethyl ketones, esters and amides. This is the first example on the use of 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones as substrates in an enantioselective reaction, which have been shown to be new ester/amide surrogates.
authors: Department de Química Orgànica-Facultat de Química, Universitat de València, C/Dr. Moliner 50, 46100 Burjassot (València) (Spain), Fax: (+34) 963544328.
authors: Amparo
authors: A
authors: Sanz-Marco
authors: Andrea
authors: A
authors: García-Ortiz
authors: Gonzalo
authors: G
authors: Blay
authors: Isabel
authors: I
authors: Fernández
authors: José R
authors: JR
authors: Pedro
keywords: alkynes; asymmetric catalysis; conjugate addition; enones; fluorine compounds