Raluca Septelean

Theoretical Investigation on the PCP(O) Linear Moiety: How to Stabilize Diphosphaallenic Derivatives

Abstract Density functional theory calculations on phosphavinylidene(oxo)phosphorane RP˭C˭P(˭O)R′ I are reported, where the R and R′ groups represent substituents with various electron-donor or electron-acceptor properties and different steric hindrance: H, F, Cl, OMe, SiH3, SiMe3, Me, Ph, Mes (2,4,6-trimethylphenyl), and Mes* (2,4,6-tri-tert-butylphenyl) and RF 2,4,6-tris(trifluoromethyl)-phenyl. The investigations provide information about the groups that seem to be the best choice for the stabilization of such systems. The influence of the substituents’ nature on the geometrical parameters and Wiberg bond orders for the P‒C bonds are discussed. Two isomers of I with a PCPO linkage (P≡C‒P(˭O)RR′ II and O˭P‒C≡PRR′ III) have also been studied. GRAPHICAL ABSTRACT