N-Phosphino- and N-Phosphonionitrilimines: From Nucleophilic to Electrophilic 1,3-Dipoles.
N-[Bis(diisopropylamino)phosphino]-C-[bis(diisopropylamino)thioxophosphoranyl]nitrilimine (1) reacts with electron-poor dipolarophiles such as maleimide, methyl vinyl ketone, and 1,4-naphthoquinone via HOMO(dipole)-controlled [2+3] cycloadditions, while N-[bis(diisopropylamino)(methyl)phosphonio]-C-[bis(diisopropylamino)thioxophosphoranyl]nitrilimine (2a) reacts with electron-rich dipolarophiles such as norbornadiene and ethyl trans-pyrrolineacrylate via LUMO(dipole)-controlled [2+3] cycloadditions. Carbon disulfide reacts with 1 via a formal [4+2] cycloaddition leading to phosphazene containing heterocycle 11 in 75% yield. Dipole 1 is cleaved by HCl, giving the corresponding (thioxophosphoranyl)diazomethane 15, while addition of HCl to 2a leads to hydrazonoyl chloride 16, in 70% isolated yield. Hydrazone 17' (95%) and phosphazine 18(80%) are obtained by a 1,3-addition of BuLi to 1 and PhOLi to 2a, respectively. Trimethylphosphine reacts with 2a by a phosphine-carbene coupling reaction, giving the ylide 20 which is isolated in 75% yield.
Palacios
Francisco
F
Departamento de Quimica Organica, Facultad de Farmacia, U.P.V./E.H.U., Apartado 450, 01080 Vitoria, Spain, and Laboratoire de Chimie de Coordination du CNRS, 205, route de Narbonne, 31077 Toulouse Cédex, France.
Pagalday
Jaione
J
Piquet
Valérie
V
Dahan
Françoise
F
Baceiredo
Antoine
A
Bertrand
Guy
G