title: Stereoselective ZrCl4-Catalyzed Mannich-type Reaction of β-Keto Esters with Chiral Trifluoromethyl Aldimines.
abstract: A method for the synthesis of fluorinated β'-amino β-dicarbonyl compounds using a Zr-catalyzed Mannich-type reaction has been developed, starting from N-protected trifluoromethyl aldimines and cyclic or acyclic β-keto esters bearing different ester residues. The in situ generated metallic complex reacted with optically pure trifluoromethyl aldimine derived from (R)-α-methylbenzylamine, giving a highly diastereoselective asymmetric Mannich-type addition with formation of a chiral quaternary center. The absolute configuration at the new chiral centers was assigned through two-dimensional nuclear Overhauser effect spectroscopic analysis coupled with computational studies.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Parise
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
authors.forename: Lucio
authors.initials: L
authors.lastname: Pellacani
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Sciubba
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Trulli
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, I-00185 Roma, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Fioravanti