title: Two isoxazolidines.
abstract: The crystal structures of trans-phenyl-1,6-dioxa-2-azaspiro[4,4]non- 3-yl ketone, C19H19NO3, and (3 alpha,3a alpha,6a alpha)-hexahydro-2-phenylfuro[3,2-d]isoxazol-3-yl phenyl ketone, C18H17NO3, are reported. In both compounds, the isoxazolidine rings adopt envelope conformations in which the O atom is bent out of the approximate plane of the other four ring atoms. Modest to negligible endo selectivities were confirmed in 1,3-dipolar cycloadditions of benzoylmethyleneaniline N-oxide with enol ethers.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles 90024-1569, USA. khan/chem.ucla.edu
authors.forename: S
authors.initials: S
authors.lastname: Niwayama
authors.forename: Y
authors.initials: Y
authors.lastname: You
authors.forename: K N
authors.initials: KN
authors.lastname: Houk
authors.forename: S I
authors.initials: SI
authors.lastname: Khan
mesh_terms: D018360:Crystallography, X-Ray; D007555:Isoxazoles / Q000737:chemistry*; D008968:Molecular Conformation; D013141:Spiro Compounds / Q000737:chemistry*
chemical_list: D007555:Isoxazoles; D013141:Spiro Compounds; C101268:hexahydro-2-phenylfuro(3,2-d)isoxazol-3-yl phenyl ketone; C101267:phenyl 2-phenyl-1,6-dioxa-2-azaspiro(4.4)non-3-yl ketone