title: Methylene-azaphosphirane as a reactive intermediate.
abstract: Reaction of the transient phosphinidene complexes R-P=W(CO)5 with N-substituted-diphenylketenimines leads unexpectedly to the novel 2-aminophosphindoles, as confirmed by an X-ray crystal structure determined for one of the derivatives. Experimental evidence for a methylene-azaphosphirane intermediate was found by using the iron-complexed phosphinidene iPr2N-P=Fe(CO)4, which affords the 2-aminophosphindole together with the novel methylene-2,3-dihydro-1H-benzo[1,3]azaphosphole. Analysis of the reaction pathways with DFT indicates that the initially formed methylene-azaphosphirane yields both phosphorus heterocycles by way of a [1,5]- or [1,3]-sigmatropic shift, respectively, followed by a H-shift. Strain underlies both rearrangements, which causes these remarkably selective conversions that can be tuned by changing the substituents.
authors.affiliation: Department of Organic and Inorganic Chemistry, Faculty of Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: J Chris
authors.initials: JC
authors.lastname: Slootweg
authors.forename: Mark J M
authors.initials: MJ
authors.lastname: Vlaar
authors.forename: Danielle J
authors.initials: DJ
authors.lastname: Vugts
authors.forename: Tanja
authors.initials: T
authors.lastname: Eichelsheim
authors.forename: Winita
authors.initials: W
authors.lastname: Merhai
authors.forename: Frans J J
authors.initials: FJ
authors.lastname: de Kanter
authors.forename: Marius
authors.initials: M
authors.lastname: Schakel
authors.forename: Andreas W
authors.initials: AW
authors.lastname: Ehlers
authors.forename: Martin
authors.initials: M
authors.lastname: Lutz
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Spek
authors.forename: Koop
authors.initials: K
authors.lastname: Lammertsma