Novel Octahedral Si and Ge Complexes with a Hexadentate Diphenol Ligand

Finely divided SiO2 dissolves in boiling methanol upon addition of the diphenol ligand 2 and excess sodium acetate along with sodium fluoride as catalyst. The sodium salt of 1, MSi, which contains hexacoordinated Si, is formed. The anion 1, MSi, is particularly stable. Thus, after 24 h in acetic acid at room temperature, its [HNEt3]⊕ salt is practically unchanged. The simple catechol complex decomposes completely under the same conditions.