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Herein we report an experimental and computational study of a family of four coordinated 14-electron complexes of Rh( iii ) devoid of agostic interactions. The complexes [X–Rh(κ 3 ( P,Si,Si )PhP( o -C 6 H 4 CH 2 Si i Pr 2 ) 2 ], where X = Cl (Rh-1), Br (Rh-2), I (Rh-3), OTf (Rh-4), Cl·GaCl 3 (Rh-5); derive from a bis(silyl)- o -tolylphosphine with isopropyl substituents on the Si atoms. All five complexes display a sawhorse geometry around Rh and exhibit similar spectroscopic and structural properties. The catalytic activity of these complexes and [Cl–Ir(κ 3 ( P,Si,Si )PhP( o -C 6 H 4 CH 2 Si i Pr 2 ) 2 ], Ir-1, in styrene and aliphatic alkene functionalizations with hydrosilanes is disclosed. We show that Rh-1 catalyzes effectively the dehydrogenative silylation of styrene with Et 3 SiH in toluene while it leads to hydrosilylation products in acetonitrile. Rh-1 is an excellent catalyst in the sequential isomerization/hydrosilylation of terminal and remote aliphatic alkenes with Et 3 SiH including hexene isomers, leading efficiently and selectively to the terminal anti-Markonikov hydrosilylation product in all cases. With aliphatic alkenes, no hydrogenation products are observed. Conversely, catalysis of the same hexene isomers by Ir-1 renders allyl silanes, the tandem isomerization/dehydrogenative silylation products. A mechanistic proposal is made to explain the catalysis with these M( iii ) complexes. 

The new material [RuGa]@NU-1000 incorporates Ru and Ga in 1.2 and 1.8 wt% respectively (molar ratio 1 : 2). It stems from the grafting of the heterobimetallic ruthenium gallate complex, [MeRu(η 6 -C 6 H 6 )(PPh 3 ) 2 ][GaMe 2 Cl 2 ] into the MOF material NU-1000. [RuGa]@NU-1000 shows enhanced adsorption of SO 2 , specially at low pressures (10 −3 bar) even when compared with other materials employing more expensive precious metals. Additionally, [RuGa]@NU-1000 samples need not be exposed to such harsh conditions for reactivation as they retain their adsorption properties after several cycles and preserve their porosity and structure. Thus, [RuGa]@NU-1000 is an excellent, selective material suitable for detection and precise quantification of SO 2 , with a lower cost compared to other MOFs incorporating precious metals.