The treatment of sodium and calcium hectorites with
2-diphenylphosphinoethyltriethoxysilane leads, by condensation of free
hydroxyl groups, to functionalized layer silicates with long-chain
diphenylphosphine groups onto which nickel chloride can be coordinated.
In these modified hectorites the fourth coordination site of the
tetrahedrally coordinated nickel is occupied by a labile solvent
molecule. On the other hand, the complex
bis(2-diphenylphosphinoethyltriethoxysilane)nickel(II) chloride prepared
beforehand also reacts with sodium hectorite under condensation; but the
square-planar coordination of the four stable ligands (two chloride and
two phosphor atoms) is maintained. This finds its expression in a
significant activity decrease in catalytic reactions as compared to the
aforementioned products.