title: Synthesis of oxaspiranic compounds through [3 + 2] annulation of cyclopropenones and donor–acceptor cyclopropanes.
abstract: The Sc(OTf)3-catalyzed [3 + 2]-annulation reaction between cyclopropenones and donor–acceptor cyclopropanes is described. The process leads directly to the formation of 4-oxaspiro[2.4]hept-1-ene derivatives in good to excellent reaction yields. Density functional theory calculations suggest that the [3 + 2]-annulation pathway is strongly preferred over the possible [3 + 3]-process.
authors.forename: Alexandra R
authors.initials: AR
authors.lastname: Rivero
authors.forename: Israel
authors.initials: I
authors.lastname: Fernández
authors.forename: Carmen Ramírez
authors.initials: CR
authors.lastname: de Arellano
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Sierra
mesh_terms: D002384:Catalysis; D003508:Cycloheptanes / Q000138:chemical synthesis* / Q000737:chemistry; D003521:Cyclopropanes; D008698:Mesylates / Q000737:chemistry*; D015394:Molecular Structure; D012538:Scandium / Q000737:chemistry*; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C000600060:4-oxaspiro(2.4)hept-1-ene; D003508:Cycloheptanes; D003521:Cyclopropanes; D008698:Mesylates; D013141:Spiro Compounds; C120343:cyclopropenone; C012077:trifluoromethanesulfonic acid; D012538:Scandium