title: Microwave-assisted organocatalytic enantioselective intramolecular aza-Michael reaction with α,β-unsaturated ketones.
abstract: An organocatalytic enantioselective intramolecular aza-Michael reaction of carbamates bearing conjugated ketones as Michael acceptors is described. By using 9-amino-9-deoxy-epi-hydroquinine as the catalyst and pentafluoropropionic acid as a co-catalyst, a series of piperidines, pyrrolidines, and the corresponding benzo-fused derivatives (indolines, isoindolines, tetrahydroquinolines, and tetrahydroisoquinolines) can be obtained in excellent yields and enantioselectivities. In addition, the use of microwave irradiation at 60 °C improves the efficiency of the process giving rise to the final products with comparable yields and enantiomeric excesses. Some mechanistic insights are also considered.
authors.affiliation: Departmento de Química Orgánica, Universidad de Valencia, 46100 Burjassot, Spain. santos.fustero@uv.es
authors.forename: Santos
authors.initials: S
authors.lastname: Fustero
authors.forename: Carlos
authors.initials: C
authors.lastname: del Pozo
authors.forename: Cristina
authors.initials: C
authors.lastname: Mulet
authors.forename: Rubén
authors.initials: R
authors.lastname: Lazaro
authors.forename: María
authors.initials: M
authors.lastname: Sánchez-Roselló
mesh_terms: D001372:Aza Compounds / Q000737:chemistry*; D002384:Catalysis; D002930:Cinchona Alkaloids / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D008872:Microwaves; D015394:Molecular Structure; D011802:Quinidine / Q000031:analogs & derivatives* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C571402:9-amino-9-deoxy-epi-hydroquinine; D001372:Aza Compounds; D002930:Cinchona Alkaloids; D007659:Ketones; D011802:Quinidine