Bildung und Charakterisierung des Dinatrium‐tetraphosphendiids ( t Bu 3 Si)NaP–PP–PNa(Si t Bu 3 ) und seines Dimeren

Abstract

Reaction of P 4 in THF or DME with 2 R * Na (R * = Si t Bu 3 ) at –78°C leads quantitatively to deep red THF or DME adducts of R * NaP–PP–PNaR * ( 3 ). According to 31 P NMR, the P 4 skeleton 3 is cis ‐configurated. On the other hand, reaction of P 4 in TBME with 2 R * Na at ‐78°C leads quantitatively to (R * NaP) 4 ( 4 ), a [2+2] cycloadduct of 3 , the Na 4 P 8 skeleton of which according to X‐ray structure analysis forms a double cube with four P atoms in the second layer and two P and two Na atoms in alternating positions in the first and in the third layer (the Na atoms are coordinated with donors). By resolving the THF adduct 3 in TBME (the TBME adduct of 4 in THF) the compound 4 (the compound 3 ) is rapidly formed under reversal of the P–PP–P configuration by way of [2+2] cycloaddition (by way of [2+2] cycloreversion). 3 and 4 are sensitive to oxidation and to protolysis. With TCNE, 3 is oxidized to R * 2 P 4 (bicyclic P 4 skeleton), with CF 3 SO 3 H, 3 may be transformed into R * 3 P 5 Na 2 X 4 THF or in (R * P 3 ) 3 and R * PH 2 .