Halil Aktas

Nucleophilic Phosphinidene Complexes: Access and Applicability

Syntheses, properties, and reactivities of nucleophilic phosphinidene complexes [L(n)M=P-R] are reviewed. Emphasis is placed on the electronic tuning of this emerging class of phosphorus reagents, using different ancillary ligands and coordinatively unsaturated transition-metal moieties. The difference in applicability of the established stable 18-electron and transient 16-electron phosphinidenes is addressed.

N-heterocyclic carbene-functionalized ruthenium phosphinidenes: what a difference a twist makes

Catalyst tuning by changing ligands is a well-established protocol in transition-metal chemistry. N-Heterocyclic carbenes (NHCs) and tertiary phosphines (R(3)P) are the ubiquitous ligand actors. Here we demonstrate that the relative sigma-donor/pi-acceptor ability of the NHC ligand itself can be influenced by a simple substituent-controlled conformational change, thereby directly impacting the reactivity of the transition-metal complex.

Iridium phosphinidene complexes: a comparison with iridium imido complexes in their reaction with isocyanides

18-Electron nucleophilic, Schrock-type phosphinidene complexes 3 [Cp*(Xy-N[triple bond]C)Ir=PAr] (Ar = Mes*, Dmp, Mes) are capable of unprecedented [1 + 2]-cycloadditions with 1 equiv of isocyanide RNC (R = Xy, Ph) to give novel iridaphosphirane complexes [Cp*(Xy-N[triple bond]C) IrPAr C=NR]. Their structures were ascertained by X-ray diffraction. Density functional theory investigations on model structures revealed that the iridaphosphirane complexes are formed from the addition of the isocyanide to 16-electron species [Cp*Ir=PAr] forming first complex 3 that subsequently reacts with another isocyanide to give the products following a different pathway than its nitrogen analogue [Cp*Ir[triple bond]Nt-Bu] 1.

η3-Diphosphavinylcarbene: A P2 Analogue of the Dötz Intermediate†

Do the twist: The reaction of in situ generated phosphinidenes with phosphaalkynes is a facile route to the new metal-coordinated eta(3)-diphosphavinylcarbene 1, which shows facile ligand-exchange reactions and undergoes an unprecedented rearrangement that involves phosphinidene complex 2 and eta(3)-phosphaalkenylphosphinidene complex 3, the 1,3 isomer of 1.