Ligand Assisted CO<sub>2</sub> Activation and Catalytic Valorization by an NHI‐Stabilized Stannylene
Debotra Sarkar, Lisa Groll, Dominik Munz, Franziska Hanusch, Shigeyoshi Inoue
Abstract
Abstract The aryl(imino)stannylene Mes Ter[N(IDipp)]Sn could be obtained by treating NHILi (NHI=N(IDipp), IDipp=C[N‐(2,6‐ i Pr 2 C 6 H 3 )CH] 2 ) with Mes TerSnCl ( Mes Ter=2,6‐Mes 2 C 6 H 3 ) and offers a unique reactivity pattern compared to conventional single site tetrylene catalyzed CO 2 reduction reactions. The Sn(II) center, stabilized by the NHI ligand enabled the sequestration and valorization of CO 2 to C1 feedstock stoichiometrically, as well as catalytically, utilizing HBpin (pin=pinacolato) as reductant. The experimental comparison with aryl(amido)stannylene Mes Ter(NPh 2 )Sn and aryl(phosphinidene)stannylene Mes Ter[P(IDipp)]Sn, as well as computational analysis, rationalize the electronic features and key role of the NHI ligand in the CO 2 reduction process. In case of the phosphorus congener, Sn−P bonding with pronounced double‐bond character is obtained, which prevents swift dissociation, thus preventing CO 2 uptake. Instead, hard/soft mismatch between tin and the NHI induces zwitterionic and single‐bond character, switching on the intermediate dissociation of Sn(II)/NHI, followed by a tin hydride mediated reduction step, and thus allows for efficient catalysis under mild conditions.