Inorganic Chemistry, Vol.45, No.1, 409-414, 2006
Synthesis and characterization of novel oxo-centered phosphanylzincates of potassium and cesium with a central Zn6O2P4 double-heterocubane cage
The hydrolysis reaction of K-2(MeZn)(2)(PSitBu(3))(2) in THF/toluene solution yields the [(MeZn)(4)Zn-2(mu(3)-PSitBu(3))(4)(mu(4)-O)(2)](4-) anions independent of the applied stoichiometry. If the applied molar ratio resembles the composition of the anion, [(thf)K](2)[(eta(6)-toluene)K](2)[(MeZn)(4)Zn-2(mu(3)-PSitBu(3))(4)(mu(4 )-O)(2)] (1) crystallizes from a mixture of THF and toluene. In the case with less water, a phosphanediylzincate moiety is bonded to this anion, and [Zn(PSitBu(3))(2)K-4(thf)(6)](2)[(MeZn)(4)Zn-2(mu(3)-PSitBu(3))(4)(mu(4) -O)(2)] (2) crystallizes. However, again the major product is 1. The same anion is also observed with larger and softer cations, and [(thf)(3)Cs-2](2)[(MeZn)(4)Zn-2(mu(3)-PSitBu(3))(4)(mu(4)-O)(2)] (3) is obtained if the cesium zincate is used in this reaction. In all of these compounds, the anion is a slightly distorted Zn6O2P4 double-heterocubane cage with a central Zn2O2 ring having Zn-O bond lengths of approximately 207 pm.