Mixed-Ligand Hydroxohydroperoxide Tin(IV) Complexes

Mixed-ligand sodium hydroxohydroperoxostannates(IV) are synthesized in hydrogen peroxide solution. On the basis of IR spectral and X-ray powder diffraction evidence, it is assumed that the obtained complexes have the structures Na(2)[Sn(OH)(2)(OOH)(4)] (I) and Na(2)[Sn(O-O)(2)(OH)(2)(H(2)O)(2)] (II). The substance of composition Na(2)Sn(OH)(3)(OOH)(3) is most likely a mixture of complexes I and II. It is shown that the Na(2)[Sn(OH)(n)(OOH)(6-n)] + nH(2)O(2) reversible arrow Na(2)[Sn(OOH)(6)] + nH(2)O reaction is reversible. The results of the X-ray powder diffraction study show that the Na[Sn(OH)(2)(OOH)(4)] complex has a structure analogous to that of Na(2)[Sn(OOH)(6)] (the octahedral environment of the tin atom consists of four OOH groups and two OH groups). Complex II, containing bridging -O-O- peroxide groups, is amorphous to X-rays. The Sn(IV) peroxide complexes are thermally unstable. At a temperature higher than 80 degrees C, two simultaneous processes take place: exothermal oxygen elimination and dehydration.