Stoichiometric Reactions of CO2 and Indium-Silylamides and Catalytic Synthesis of Ureas.

The indium compounds In(N(SiMe3 )2 )2 Cl⋅THF (2) and In(N(SiMe3 )2 )Cl2 ⋅(THF)n (3) were shown to react with CO2 to give [(Me3 Si)2 N)InX(μ-OSiMe3 )]2 (X=N(SiMe3 )2 4, Cl 5). 0.05-2.0 mol % of the species 3 acts as a pre-catalyst for the conversion of aryl and alkyl silylamines under CO2 (2-3 atm) to give the corresponding ureas in 70-99 % yields. A proposed mechanism is supported by experimental and computational data.