Bifunctional diphosphorus Lewis acids from cyclodiphosphadiazanes

A Systematic Survey of the Reactivity of Chlorinated N2 P2 , NP3 and P4 Ring Systems

The reactivity of the four-membered NP3 ring system [RN(μ-PCl)2 PR] (R=Mes*=2,4,6-tri-tert-butylphenyl) towards Lewis acids, Lewis bases, and reducing agents was investigated. Comparisons with the literature-known, analogous cyclic compounds [ClP(μ-NR)]2 (R=Ter=2,6-dimesitylphenyl) and [ClP(μ-PR)]2 (R=Mes*) are drawn, to obtain a better systematic understanding of the reactivity of cyclic NP species. Apart from experimental results, DFT computations are discussed to further the insight into bonding and electronic structure of these compounds.

Tetra-cationic imidazoliumyl-substituted phosphorus–sulfur heterocycles from a cationic organophosphorus sulfide

The formation of novel tetracationic cyclo-P₄S₄ derivatives [LPS]₄⁴⁺via oligomerization of [LPS]⁺ is presented. Subsequent deoligomerization- and dismutation reactions induced by 4-dimethylaminopyridine are discussed herein.

Low-Temperature Isolation of the Bicyclic Phosphinophosphonium Salt [Mes*2P4Cl][GaCl4]

The reaction of [ClP(μ-PMes*)]2 (1) with the Lewis acid GaCl3 yielded a hitherto unknown tetraphosphabicyclo[1.1.0]butan-2-ium salt, [Mes*P4(Cl)Mes*][GaCl4] (3[GaCl4]), which incorporates a positively charged phosphonium center within its bicyclic P4 scaffold. The formation of the title compound was studied by means of low-temperature NMR experiments. This led to the identification of an intermediate cyclotetraphosphenium cation, which was trapped by reaction with dimethylbutadiene (dmb). All of the compounds were fully characterized by experimental and computational methods.

The chemistry of cationic polyphosphorus cages--syntheses, structure and reactivity

The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages.

The aim of this review is to provide a comprehensive view of the chemistry of cationic polyphosphorus cages. The synthetic protocols established for their preparation, which are all based on the functionalization of P₄, and their intriguing follow-up chemistry are highlighted. In addition, this review intends to foster the interest of the inorganic, organic, catalytic and material oriented chemical communities in the versatile field of polyphosphorus cage compounds. In the long term, this is envisioned to contribute to the development of new synthetic procedures for the functionalization of P₄ and its transformation into (organo-)phosphorus compounds and materials of added value.

Structure and bonding of novel acyclic bisaminoarsenium cations

The synthesis and characterization of a salt bearing a labile bisaminoarsenium cation of the type {[(Me3Si)2N]2As}(+) (9a) are described, which was obtained in the reaction of the chloroarsane [(Me3Si)2N]2AsCl (8) with GaCl3. Reacting 8 with AgOTf did not yield an arsenium salt, but the cyclo-diarsadiazane [(Me3Si)2NAs-μ-NSiMe3]2 (11) was obtained in excellent yields. Moreover, the reactivity of the analogous antimony species [(Me3Si)2N]2SbCl (12) was studied. In the reaction with GaCl3, the aminochlorostibenium salt [(Me3Si)2NSbCl](+)[(Me3Si)2N(GaCl3)2](-) (5) was isolated. In the reaction with AgOTf, substitution of the chlorine in 12 resulted in the formation of [(Me3Si)2N]2SbOTf (13), a compound with significant stibenium character. All new compounds have been fully characterized by means of X-ray, vibrational spectroscopy, CHN analysis, and NMR experiments. All compounds were further investigated by means of density functional theory and the bonding situation was accessed by natural bond orbital (NBO) analysis.

On the synthesis and reactivity of highly labile pseudohalogen phosphenium ions

The synthesis and characterization of salts bearing highly labile pseudohalogen-substituted aminophosphenium cations of the type [(Me3Si)2NPX][GaCl4] (X = NCO, NCS, O(SiMe3)) and their respective reactivity toward Lewis bases (4-dimethylaminopyridine, dmap) and dienes (2,3-dimethyl-1,3-butadiene, dmb; 1,3-cyclo-hexadiene, chd) are described. As π-acidic species, aminophosphenium cations react with dmap at low temperatures to yield adduct salts of the type [(Me3Si)2NP(dmap)X][GaCl4] (X = Cl, N3, NCO) which were fully characterized. In the reaction with dienes at -50 °C, salts bearing phospholenium cations were obtained that could be structurally characterized. The crystal structures of novel 7-phosphanorbornenium cations of the type [(Me3Si)2NP(C6H8)X][GaCl4] (X = Cl, N3, NCO) are reported. All compounds were further investigated by means of density functional theory, and the bonding situation was accessed by Natural Bond Orbital (NBO) analysis.

Preparation of the [(DippNP)2(P4)2]2+-dication by the reaction of [DippNPCl]2 and a Lewis acid with P4

The controlled activation of white phosphorus, P(4), provides a key entry point into many aspects of phosphorus chemistry. The activation and functionalization of P(4) by N-heterocyclic carbenes and carbene-like main group element fragments is of considerable current interest. In this communication, we report on the first use of a disguised bifunctional Lewis acid [DippNP](2)(2+) obtained from the cyclo-1,3-diphospha-2,4-diazane [DippNPCl](2) for P(4) functionalization. This has enabled the targeted preparation of novel mono- and dicationic phosphorus-rich clusters [(DippNP)(2)(P(4))Cl](+) and [(DippNP)(2)(P(4))(2)](+). The utilization of such a bifunctional phosphenium cation represents a rational and potentially versatile synthetic method for the assembly of large clusters using P(4) as a building block.