Iminophosphonamido stannylenes enable quantitative CO2 conversion to isocyanates

Iminophosphonamido-supported silylaminostannylenes activate CO₂ to afford siloxystannylene and isocyanates via carbamatostannylene intermediates. DFT calculations support a two-step rearrangement involving nucleophilic attack and silyl migration, offering a rare example of a main-group CO₂ valorisation through isocyanate formation.