Iron(II)‐Catalyzed Hydrophosphination of Isocyanates

The first transition metal catalyzed hydrophosphination of isocyanates is presented. The use of low‐coordinate iron(II) precatalysts leads to an unprecedented catalytic double insertion of isocyanates into the P−H bond of diphenylphosphine to yield phosphinodicarboxamides [Ph 2 PC(=O)N(R)C(=O)N(H)R], a new family of derivatized organophosphorus compounds. This remarkable result can be attributed to the low‐coordinate nature of the iron(II) centers whose inherent electron deficiency enables a Lewis‐acid mechanism in which a combination of the steric pocket of the metal center and substrate size determines the reaction products and regioselectivity.