title: Organocatalytic Asymmetric Biginelli-like Reaction Involving Isatin.
abstract: The first asymmetric, Brønsted acid catalyzed Biginelli-like reaction of a ketone has been developed, employing N-substituted isatins as carbonyl substrates, and urea and alkyl acetoacetates as further components. BINOL-derived phosphoric acid catalysts have been used to achieve the synthesis of a small library of chiral, enantioenriched spiro(indoline-pyrimidine)-diones derivatives. The absolute configuration of the new spiro stereocenter was assessed on diastereoisomeric derivatives through computer-assisted NMR spectroscopy. X-ray diffractometry allowed the disclosure of the overall molecular conformation in the solid state and the characterization of the crystal packing of a Br-substituted Biginelli-like derivative, while computational studies on the reaction transition state allowed us to rationalize the stereochemical outcome.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via C. Golgi 19, 20133, Milano, Italy.
authors.forename: Mattia
authors.initials: M
authors.lastname: Stucchi
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via C. Golgi 19, 20133, Milano, Italy.
authors.forename: Giordano
authors.initials: G
authors.lastname: Lesma
authors.affiliation: Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano , via L. Mangiagalli 25, 20133, Milano, Italy.
authors.forename: Fiorella
authors.initials: F
authors.lastname: Meneghetti
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via C. Golgi 19, 20133, Milano, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Rainoldi
authors.affiliation: Dipartimento di Chimica, Materiali ed Ing. Chimica "Giulio Natta", Politecnico di Milano , p.zza Leonardo da Vinci 32, 20133, Milano, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Sacchetti
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Milano , via C. Golgi 19, 20133, Milano, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Silvani