Surface organometallic chemistry has been reviewed with a special focus on environmentally relevant transformations (C–H activation, CO2 conversion, oxidation).

Reactive surface species immobilized inside porous materials with suitably small windows can be studied by DNP SENS.

* Formulated samples were previously calcined at 700 °C for 7 h applying 5 °C•min-1 heating ramp. ZSM-5 was calcined at 550 °C for 7 h applying 5 °C•min-1 heating ramp xK:yZ:zB abbreviation used for indicate the composition of formulated catalysts (mass ratio) where K stands from kaolin, Z from zeolite (ZSM-5) and B from binder (Al2Cl(OH)5). ** Formulation was not ball-milled prior the spray drying, the rest of the treatment such as calcination temperature was perceived unchanged.

We present a new generation of "true vicinal" functions well-distributed on the inner surface of SBA15: [(≡Si-NH2)(≡Si-OH)] (1) and [(≡Si-NH2)2] (2). From these amine-modified SBA15s, two new well-defined surface organometallic species [(≡Si-NH-)(≡Si-O-)]Zr(CH2tBu)2 (3) and [(≡Si-NH-)2]Zr(CH2tBu)2 (4) have been obtained by reaction with Zr(CH2tBu)4. The surfaces were characterized with 2D multiple-quantum (1)H-(1)H NMR and infrared spectroscopies. Energy-filtered transmission electron microscopy (EFTEM), mass balance, and elemental analysis unambiguously proved that Zr(CH2tBu)4 reacts with these vicinal amine-modified surfaces to give mainly bipodal bis(neopentyl)zirconium complexes (3) and (4), uniformly distributed in the channels of SBA15. (3) and (4) react with hydrogen to give the homologous hydrides (5) and (6). Hydrogenolysis of n-butane catalyzed by these hydrides was carried out at low temperature (100 °C) and low pressure (1 atm). While (6) exhibits a bis(silylamido)zirconium bishydride, [(≡Si-NH-)2]Zr(H)2 (6a) (60%), and a bis(silylamido)silyloxozirconium monohydride, [(≡Si-NH-)2(≡Si-O-)]ZrH (6b) (40%), (5) displays a new surface organometallic complex characterized by an (1)H NMR signal at 14.46 ppm. The latter is assigned to a (silylimido)(silyloxo)zirconium monohydride, [(≡Si-N═)(≡Si-O-)]ZrH (5b) (30%), coexistent with a (silylamido)(silyloxo)zirconium bishydride, [(≡Si-NH-)(≡Si-O-)]Zr(H)2 (5a) (45%), and a silylamidobis(silyloxo)zirconium monohydride, [(≡Si-NH-)(≡Si-O-)2]ZrH (5c) (25%). Surprisingly, nitrogen surface ligands possess catalytic properties already encountered with silicon oxide surfaces, but interestingly, catalyst (5) with chelating [N,O] shows better activity than (6) with chelating [N,N].

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