Supersilylverbindungen des Phosphors, V [1]. Darstellung, Struktur und Reaktivität des Pentaphosphids (tBu₃Si)₃P₅Na₂ und des Pentaphosphans (tBu₃Si)₃P₅[2] / Supersilyl Compounds of Phosphorus, V [1]. Preparation, Structure, and Reactivity of the Pentaphosphide (tBu₃Si)₃P₅Na₂ and the Pentaphosphane (tBu₃Si)₃P₅ [2]

The orange THF adduct (tBu₃Si)₃P₅Na₂ (THF)₄ of the pentaphosphide (tBu₃Si)₃P₅Na₂ (3) has been prepared, (i) by protolysis of the tetraphosphide (tBu₃Si)₂P₄Na₂(THF)_n (2) with CF₃CO₂H in THF (molar ratio 2 : 1 ) , (ii) by dissolving crystalline 2 in toluene, and (iii) by the reaction of P₄ with tBu₃SiNa(THF)₂ in benzene (molar ratio 1 : 4). According to an X-ray structural analysis, the THF adduct of 3 contains a P₃ ring with two PNa(SitBu₃) substituents in cis position and one SitBu₃ substituent in trans position to the former groups. The protolysis of 3 with CF₃CO₂H leads to the pentaphosphane P₅H₂(SitBu₃)₃ (9), the silylation of 3 with Me₂SiCl₂ to the pentaphosphane P₅ (SiMe₂)(SitBu₃)₃ (10), and the oxidation of 3 with C₂(CN)₄ to the pentaphosphane P₅(SitBu₃)₃ (5). The structures of 3,5,9, and 10 have been assigned from ³¹P and ²⁹Si NMR data. The pentaphosphane 5 contains a hitherto unknown P₅ backbone of a P₃ ring anellated with a P₄ ring.