Postfunctionalization of periodic mesoporous silica SBA-1 with magnesium(II) and iron(II) silylamides.

Magnesium silylamide complexes MgN(SiHMe(2))(2)(THF)(2) and MgN(SiPhMe(2))(2) were synthesized according to transsilylamination and alkane elimination protocols, respectively, utilizing MgN(SiMe(3))(2)(THF)(2) and Mg(n-Bu) as precursors. Cage-like periodic mesoporous silica SBA-1 was treated with donor solvent-free dimeric Mg{N(SiHMe(2))(2)}(2), Mg{N(SiMe(3))(2)}(2) and monomeric MgN(SiPhMe(2))(2), producing hybrid materials [Mg(NR(2))(2)]@SBA-1 with magnesium located mainly at the external surface. Consecutive grafting of Mg{N(SiHMe(2))(2)}(2) and Fe(II){N(SiHMe(2))(2)}(2) onto SBA-1 led to heterobimetallic hybrid materials which exhibit complete consumption of the isolated surface silanol groups, evidencing intra-cage surface functionalization. All materials were characterized by DRIFT spectroscopy, nitrogen physisorption and elemental analysis.