title: Phosphinidene Reactivity of a Transient Vanadium P≡N Complex.
abstract: Toward the preparation of a coordination complex of the heterodiatomic molecule PN, P≡N-V(N[tBu]Ar)3(1, Ar = 3,5-Me2C6H3), we report the use of ClPA (A = C14H10, anthracene) as a formal source of phosphorus(I) in its reaction with Na[NV(N[tBu]Ar)3] (Na[4]) to yield trimeric cyclo-triphosphane [PNV(N[tBu]Ar)3]3(3) with a core composed exclusively of phosphorus and nitrogen. In the presence of NapS2(peri-1,8-naphthalene disulfide), NapS2P-NV(N[tBu]Ar)3(6) is instead generated in 80% yield, suggesting trapping of transient 1. Upon mild heating, 3 readily fragments into dimeric [PNV(N[tBu]Ar)3]2(2), while in the presence of bis(trimethylsilyl)acetylene or cis-4-octene, the respective phosphirene (Ar[tBu]N)3VN-PC2(SiMe3)2(7) or phosphirane (Ar[tBu]N)3VN-P(C8H16) (8) compounds are generated. Kinetic data were found to be consistent with unimolecular decay of 3, and [2+1]-cycloaddition with radical clocks ruled out a triplet intermediate, consistent with intermediate 1 reacting as a singlet phosphinidene. In addition, both 7 and 8 were shown to reversibly exchange cis-4-octene and bis(trimethylsilyl)acetylene, serving as formal sources of 1, a reactivity manifold traditionally reserved for transition metals.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Courtemanche
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Wesley J
authors.initials: WJ
authors.lastname: Transue
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Christopher C
authors.identifier: 0000-0003-2568-3269
authors.initials: CC
authors.lastname: Cummins