Trisodium Henicosaphosphide

Sodium powder is prepared by melting S g of carefully cleaned cut sodium metal in 250 mL of boiling xylenes. After removal of the heating bath a slow stream of nitrogen is passed over the solvent, and a high speed stirrer (20,000 rpm, e.g., Ultra-Turrax, model T 18/10) is introduced and run for 15 s. The finely divided metal is filtered and washed (three l5-mL portions of pentane) under inert gas and sucked dry. It can be stored in a dry box for months without loss of activity.  

Trisodium henicosaphosphide is obtained using equipment similar to that 

Trisodium henicosaphosphide is obtained as an adduct with 15 mol of THF and forms orange needle-shaped crystals, which liquefy above — 10°C. At room temperature the melt undergoes a slow disproportionation. The crystals are slightly sensitive to oxidation but strongly sensitive to hydrolysis. A solution of NajPji in THF-DMF ( 2 1) exhibits a P NMR spectrum with seven signal groups at d + 72, -1-61, — 15, -108,-118, —146, and 

In the alkylation or silylation of trisodium henicosaphosphide the monometalated henicosaphosphanes(3) NaP2iR2 [R = CH3, C2H5, J-C3H7, and (CH3)3Si] have been obtained as the final products. A substitution on the central one-atom bridge of the P2i ion does not occur for steric reasons. 

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TRILITHIUM HEPTAPHOSPHIDE, DILITHIUM HEXADECAPHOSPHIDE, AND TRISODIUM HENICOSAPHOSPHIDE... 

Trilithium heptaphosphide, dilithium hexadecaphosphide, and trisodium henicosaphosphide are polyphosphides with isolated anions in the solid state as well as in solution. These metalated poly phosphorus compounds are of interest because of their structural relationship to the phosphorus hydrides (phosphanes) and organophosphanes P.R and particularly because of their potential use as building blocks for the syntheses of polyphosphorus compounds. 

The stability of the heptaphosphanortricyclene cage is emphasized by its presence as the terminal group in trisodium henicosaphosphide Na3P21, which is preferentially silylated terminally rather than at the middle phosphide atom to give 54 (equation 53)68. 

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