Silicon‐Based Azo Compound‐Mediated CO Activation and N ₂ Release

Abstract Silicon‐substituted azo compounds featuring Si─N═N─Si linkages remain elusive in main‐group chemistry. Herein, we report the synthesis of a silicon‐based azo compound generated directly from a mixed‐valent silaiminyl–silylene precursor and a bulky organic azide. Unlike classical iminosilane formation, this reaction affords a thermally stable Si(IV)–azo species. Upon treatment with carbon monoxide (CO), this compound undergoes N 2 extrusion, complete C≡O bond cleavage, and formation of a formal Si(II)/Si(IV) product in which an oxygen atom bridges both silicon centers. Notably, the transformation incorporates the carbon atom into a DippNC byproduct via ligand rearrangement. A similar transformation occurs upon reaction with Fe(CO) 5 , wherein N 2 release and CO cleavage also occur, but with the resulting Fe(CO) 4 fragment coordinating to the silicon center. These results demonstrate a rare example of silicon based azo‐mediated small‐molecule activation and highlight the potential of silicon‐based systems for multi‐electron redox chemistry typically associated with transition metals.