SUPERSILYL-CONTAINING PHOSPHORUS-COMPOUND S .3. FORMATION AND CHARACTERIZATION OF THE DISODIUM TETRAPHOSPHENEDIIDE(TBU(3)SI)NAP-P=P-PNA(SITBU(3)) AND OF ITS DIMER
N. Wiberg et al., SUPERSILYL-CONTAINING PHOSPHORUS-COMPOUND S .3. FORMATION AND CHARACTERIZATION OF THE DISODIUM TETRAPHOSPHENEDIIDE(TBU(3)SI)NAP-P=P-PNA(SITBU(3)) AND OF ITS DIMER, Chemische Berichte, 130(1), 1997, pp. 135-140
Reaction of P-4 in THF or DME with 2 RNa (R* = SitBu(3)) at -78 degre
es C leads quantitatively to deep red THF or DME adducts of RNaP-P=P-
PNaR (3). According to P-31 NMR, the P-4 skeleton 3 is cis-configurat
ed. On the other hand, reaction of P-4 in TBME with 2 RNa at -78 degr
ees C leads quantitatively to (RNaP)(4)P-4 (4), a [2+2] cycloadduct o
f 3, the Na4P8 skeleton of which according to X-ray structure analysis
forms a double cube with four P atoms in the second layer and two P a
nd two Na atoms in alternating positions in the first and in the third
layer (the Na atoms are coordinated with donors). By resolving the TH
F adduct 3 in TBME (the TBME adduct of 4 in THF) the compound 4 (the c
ompound 3) is rapidly formed under reversal of the P-P=P-P configurati
on by way of [2+2] cycloaddition (by way of [2+2] cycloreversion). 3 a
nd 4 are sensitive to oxidation and to protolysis. With TONE, 3 is oxi
dized to RP-2(4) (bicyclic P-4 skeleton), with CF3SO3H, 3 may be tran
sformed into R3P5Na2 x 4 THF or in (R*P-3)(3) and R*PH2.