An isolable stannaimine and its cycloaddition/metathesis reactions with carbon dioxide

Abstract

An N-heterocyclic stannylene :Sn(NON^Ad) (NON^Ad = [O(SiMe₂NAd)₂]²⁻, Ad = 1-adamantyl), reacts rapidly with 2,4,6-tricyclohexylphenyl azide (TCHP)N₃, affording a stannaimine, (NON^Ad)SnN(TCHP). Solutions of (NON^Ad)SnN(TCHP) react immediately with carbon dioxide (CO₂) to give a [2+2]-cycloaddition product, which, upon heating, subsequently engages in a metathesis process to give [Sn(NON^Ad)(μ-O)]₂ and the bulky isocyanate, (TCHP)NCO.