Synthesis and grafting of CAN-derived tetravalent cerium alkoxide silylamide precursors onto mesoporous silica MCM-41

摘要

The heteroleptic tetravalent cerium complex [Ce(OiPr) _3{N(SiMe_3)_2}]_2 was synthesised by treating ceric ammonium nitrate (CAN) sequentially with sodium isopropoxide and lithium bis(trimethylsilyl)amide in THF. The trivalent ate complex [Ce(OiPr)_2{N(SiMe_3)_2]_2}][Li(thf) _2] was also isolated from these reaction mixtures. A transsilylamination reaction of [Ce(OiPr)_3{N(SiMe_3) _2}]_2 with tetramethyldisilazane produced a considerable amount of homoleptic Ce[N(SiHMe_2)_2]_4. The polymeric complex [Li_2Ce_2(OiPr)_(10)(1,4-dioxane)] _n was isolated as an additional ligand redistribution product. When tetravalent complexes Ce[N(SiHMe_2)_2]_4, Ce[N(SiMe_3)_2]_3Cl and Cp_3CeCl were allowed to react with samples of periodic mesoporous silica MCM-41, Ce(iv) hybrid materials were produced. All hybrid materials were characterised via N_2 physisorption, elemental analysis and DRIFT spectroscopy.