title: Catalytic enantioselective protonation of nitronates utilizing an organocatalyst chiral only at sulfur.
abstract: The highly enantioselective protonation of nitronates formed upon the addition of α-substituted Meldrum's acids to terminally unsubstituted nitroalkenes is described. This work represents the first enantioselective catalytic addition of any type of nucleophile to this class of nitroalkenes. Moreover, for the successful implementation of this method, a new type of N-sulfinyl urea catalyst with chirality residing only at the sulfinyl group was developed, thereby enabling the incorporation of a diverse range of achiral diamine motifs. Finally, the Meldrum's acid addition products were readily converted to pharmaceutically relevant 3,5-disubstituted pyrrolidinones in high yield.
authors.affiliation: Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States.
authors.forename: Kyle L
authors.initials: KL
authors.lastname: Kimmel
authors.forename: Jimmie D
authors.initials: JD
authors.lastname: Weaver
authors.forename: Melissa
authors.initials: M
authors.lastname: Lee
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Ellman
mesh_terms: D000475:Alkenes / Q000737:chemistry; D002384:Catalysis; D004146:Dioxanes / Q000737:chemistry; D015394:Molecular Structure; D009589:Nitrogen Oxides / Q000737:chemistry*; D011522:Protons; D013237:Stereoisomerism; D013455:Sulfur / Q000737:chemistry*; D014508:Urea / Q000031:analogs & derivatives / Q000737:chemistry*
chemical_list: D000475:Alkenes; D004146:Dioxanes; D009589:Nitrogen Oxides; D011522:Protons; C015388:nitrones; D013455:Sulfur; D014508:Urea; C076489:Meldrum's acid