title: Yb(NTf2)3-catalyzed [3 + 3] cycloaddition between isatin ketonitrones and cyclopropanes to construct novel spiro[tetrahydro-1,2-oxazine]oxindoles.
abstract: Yb(NTf(2))(3)-catalyzed [3 + 3] cycloaddition between isatin ketonitrones and cyclopropanes is described. A variety of spiro[tetrahydro-1,2-oxazine]oxindoles were obtained in moderate to good yields along with good regioselectivities. This is the first example of the intermolecular [3 + 3] cycloaddition between ketone-derived nitrones and cyclopropanes.
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, PR China.
authors.forename: Hai-Bin
authors.initials: HB
authors.lastname: Yang
authors.forename: Min
authors.initials: M
authors.lastname: Shi
mesh_terms: D002384:Catalysis; D003500:Cyclization; D061565:Cycloaddition Reaction; D003521:Cyclopropanes / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D007510:Isatin / Q000737:chemistry*; D058116:Lewis Acids / Q000737:chemistry*; D008958:Models, Molecular; D009589:Nitrogen Oxides / Q000737:chemistry*; D010078:Oxazines / Q000737:chemistry*; D000078183:Oxindoles; D013141:Spiro Compounds / Q000737:chemistry*; D013237:Stereoisomerism; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D003521:Cyclopropanes; D007211:Indoles; D058116:Lewis Acids; D009589:Nitrogen Oxides; D010078:Oxazines; D000078183:Oxindoles; D013141:Spiro Compounds; C015388:nitrones; C022960:2-oxindole; D007510:Isatin; D015018:Ytterbium