A "Push-Pull" Stabilized Phosphinidene Supported by a Phosphine-Functionalized β-Diketiminato Ligand

The use of a bis(diphenyl)phosphine functionalized β-diketiminato ligand, [HC{(CH3 )C}2 {(ortho-[P(C6 H5 )2 ]2 C6 H4 )N}2 ]- (PNac), as a support for germanium(II) and tin(II) chloride and phosphaketene compounds, is described. The conformational flexibility and hemilability of this unique ligand provide a versatile coordination environment that can accommodate the electronic needs of the ligated elements. For example, chloride abstraction from [(PNac)ECl] (E=Ge, Sn) affords the cationic germyliumylidene and stannyliumylidene species [(PNac)E]+ in which the pendant phosphine arms associate more strongly with the Lewis acidic main group element centers, providing further electronic stabilization. In a similar fashion, chemical decarbonylation of the germanium phosphaketene [(PNac)Ge(PCO)] with tris(pentafluorophenyl)borane affords a "push-pull" stabilized phosphinidene in which one of the phosphine groups of the ligand backbone associates with the low valent phosphinidene center.

Recent highlights in mixed-coordinate oligophosphorus chemistry

This review aims to highlight and comprehensively summarize recent developments in the field of mixed-coordinate phosphorus chemistry. Particular attention is focused on the synthetic approaches to compounds containing at least two directly bonded phosphorus atoms in different coordination environments and their unexpected properties that are derived from spectroscopic and crystallographic data. Novel substance classes are discussed in order to supplement previous reviews about mixed-coordinate phosphorus compounds.

P-chiral 1-phosphanorbornenes: from asymmetric phospha-Diels–Alder reactions towards ligand design and functionalisation

A building set for chiral phosphorus. The principle of stereotopic face differentiation is successfully applied to a PC bond. A divergent ligand synthesis is feasible after reduction of the chiral auxiliary.