Asymmetric Organocatalytic 1,4-Addition Reactions Starting from Enals with gem-Difluoroalkyl Side Chains
Résumé
gem-Difluoroenals are excellent substrates for asymmetric organocatalytic 1,4-additions of thiols and anilines. By using diarylsilylprolinol ether as a catalyst, good to excellent yields with ee values in the same range (up to 98%) were obtained. The CF2R group strongly activates the enals towards these organocatalytic additions.