Stimuli‐Responsive Frustrated Lewis‐Pair‐Type Reactivity of a Tungsten Iminoazaphosphiridine Complex

Reactions of 3‐imino‐azaphosphiridine complexes 1 a,b with carbodiimides 2 a,b , isocyanates 3 a,b , and carbon dioxide are described. Whereas exchange of the carbodiimide unit occurs in the first case, an overall ring expansion takes place with phenyl isocyanate ( 3 a ) and carbon dioxide to yield complexes 4 and 5 bearing novel 1,3,5‐oxazaphospholane ligands; the isopropyl derivative 3 b did not react under these conditions. DFT calculations provide insight into the pathway of the reaction with carbon dioxide with model complex 1 c , revealing effects of initial non‐covalent interactions with the substrate onto the ring bonding, thus triggering an initially masked frustrated Lewis‐pair‐type behavior.