Reduction of carbodiimides by a dialumane through insertion and cycloaddition.

The dialumane [L2-AlII-AlIIL2-] (L = [(2,6-iPr2C6H3)NC(Me)]2; 1) reacts with carbodiimides, RN[double bond, length as m-dash]C[double bond, length as m-dash]NR (R = Cy, iPr), through insertion, [2+4] cycloaddition, and a hydrogen transfer process. However, with the bulkier carbodiimides (R = dipp = 2,6-iPr2C6H3, tBu), the reactions are sterically controlled and lead to the formamidinate products.