Synthetic Applications of Metalated Phosphonium Ylides

[{HC(CMeNAr)2}2Al2P4] (Ar=2,6‐iPr2C6H3): A Reduction to a Formal {P4}4−Charged Species

“…Organophosphorus compounds can be used as reagents [1] and as ligands for innumerable complexes in catalytic processes.[2] The reactions of transition-metal complexes with white phosphorus have been extensively studied and have resulted in a large variety of P x ligands with unpredictable structures.[3] Among them, only one compound [Cp* 2 (CO) 2 Co 2 P 4 ] (Cp* = C 5 Me 5 ) [4] with a {P 4 } 4À species is reported. However, the reactions of the P 4 molecule with main-group complexes are limited to a few examples, [(AlCp*) 6 P 4 ], [5a] [(GaR) 3 P 4 ] (R= (SiMe 3 ) 3 C), [5b] and [Ga 2 P 4 tBu 6 ].…”

Synthesis of 1,3,5,2λ5‐Triazaphosphinines by Intramolecular Cyclisation of (N‐Cyanophosphorimidoyl)guanidines and Diguanidinophosphonium Chlorides

“…[3] This reaction did not proceed, however, in the presence of the less nucleophilic amides RC(O)NH 2 in place of substituted amines. On the other hand, the oxidation of phosphorus(iii) compounds with azides (Staudinger reaction [2] ), such as cyanic azide, is a very clean method by which to introduce an imide function.…”

“…[15,16] The conditions applied depend on the acidity of the ammonium salts used, their reactivities decreasing in the order [PhNH 3 ]Cl (pK a ϭ 4.63), morpholinium hydrochloride (morph·HCl) (pK a ϭ 8.21), benzylammonium chloride (pK a ϭ 9.33) and [tBuNH 3 ]Cl (pK a ϭ 10.83). The aryl and morpholinium compounds 4 rearranged even in acetonitrile at reflux, but in the case of the alkylammonium salts the rearrangement took place only at temperatures higher than the melting point of 4.…”

“…[5,6] While the first compound of the nonstabilised type, Li[tBu 2 P(NH) 2 ], was first synthesised in 1969, [7] synthetic strategies for the preparation of stabilised diazadiylides have appeared only recently. [5,6] Generally, non-and semi-stabilised diazadiylides can be prepared by lithiation of diaminophosphonium salts [2,3,8] However, this synthetic route failed for the preparation of stabilised diazadiylides 2c. In the literature, series of cyanamidophosphates such as Na 3 [PSO 3Ϫn (NCN) n ] (n ϭ 1Ϫ3), or the phosphinates and phosphonates analogues, like Na[Ph 2 P(O)NCN] or Na 2 [PhP(O)(NCN) 2 ], are described; [9Ϫ11] therefore the synthesis of M[Ph 2 P(NCN) 2 ] (3) as the first stabilised diazadiylide appeared promising.…”

“…They can be used, for instance, as precursors of primary and secondary amines [3] and have also afforded a new approach towards ketenimines Ph 2 CϭCϭNR [R ϭ alkyl, Ph, C(O)Ph] under very mild conditions. [13] We now report the synthesis of sodium phosphonium diylide 3 and its reactivity towards substituted amine hydrochlorides [ …”