Abstract
The reactivities of phosphanylphosphinidene complexes [(DippN)2W(Cl)(η2-P–PtBu2)]− (1), [(pTol3P)2Pt(η2-P=PtBu2)] (2), and [(dppe)Pt(η2-P=PtBu2)] (3) toward dihaloalkanes and methyl iodide were investigated. The reactions of the anionic tungsten complex (1) with stochiometric Br(CH2)nBr (n = 3, 4, 6) led to the formation of neutral complexes with a tBu2PP(CH2)3Br ligand or neutral dinuclear complexes with unusual tetradentate tBu2PP(CH2)nPPtBu2 ligands (n = 4, 6). The methylation of platinum complexes 2 and 3 with MeI yielded neutral or cationic complexes bearing side-on coordinated tBu2P–P-Me moieties. The reaction of 2 with I(CH2)2I gave a platinum complex with a tBu2P—P—I ligand. When the same dihaloalkane was reacted with 3, the P—P bond in the phosphanylphosphinidene ligand was cleaved to yield tBu2PI, phosphorus polymers, [(dppe)PtI2] and C2H4. Furthermore, the reaction of 3 with Br(CH2)2Br yielded dinuclear complex bearing a tetraphosphorus tBu2PPPPtBu2 ligand in the coordination sphere of the platinum. The molecular structures of the isolated products were established in the solid state and in solution by single-crystal X-ray diffraction and NMR spectroscopy. DFT studies indicated that the polyphosphorus ligands in the obtained complexes possess structures similar to free phosphenium cations tBu2P+=P−R (R = Me, I) or (tBu2P+=P)2.
Highlights
The properties of phosphido and phosphinidene complexes of transition metals (TM) as synthetic tools in organic and inorganic chemistry have recently been intensely studied.[1]
Phosphinidene complexes can be divided into two classes: electrophilic, which are often very reactive transient species[2−6] except for the stable phosphinidene complexes of cobalt and vanadium described by Carty group,[7,8] and nucleophilic, which are generally isolable.[5,6,9]
Our studies showed that phosphanylphosphinidene complexes of tungsten and platinum are valuable substrates in the synthesis of new diphosphorus ligand species and new polydentate phosphorus ligands
Summary
The properties of phosphido and phosphinidene complexes of transition metals (TM) as synthetic tools in organic and inorganic chemistry have recently been intensely studied.[1] Formally, phosphinidene complexes can be divided into two classes: electrophilic, which are often very reactive transient species[2−6] except for the stable phosphinidene complexes of cobalt and vanadium described by Carty group,[7,8] and nucleophilic, which are generally isolable.[5,6,9] It is commonly accepted that the electrophilicity versus nucleophilicity of a phosphinidene complex is primarily determined by the electronic properties of the spectator ligands10−acceptor ligands (especially CO) that result in electrophilic complexes, whereas donor spectator ligands, such as NR and PR3, result in nucleophilic complexes From this point of view, phosphanylphosphinidene complexes, which we discuss in this paper ([(DippN)2W(Cl)(η2-P−PtBu2)]− (1),11 [(pTol3P)2Pt(η2P PtBu2)] (2),[12] and [(dppe)Pt(η2-P PtBu2)] (3)13) must be considered nucleophilic species (Scheme 1).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
