Theoretical study on the reaction of Cp * (pentamethylcyclopentadienyl)(Cl)Zr(diene) with isonitriles

The migratory insertion of isonitriles into metal C bonds is a potentially important method for the formation of C C bonds in organic and pharmaceutical syntheses. In this context, the reaction mechanism of Cp * (pentamethylcyclopentadienyl)(Cl)Zr(diene) with isonitriles was studied using density functional theory calculations. Zr imido complexes and α-methylene cyclopentenimines are the confirmed products for N-t Bu-, N -2,6-diMePh-, and N -1-adamantyl-substituted isonitriles, whereas six-membered zirconacycles are the thermodynamically favored products for Me- and Et-substituted isonitriles. The β-H elimination pathway is responsible for the formation of α-methylene cyclopentenimines and zirconacycles. The kinetically favored products for MeNC and EtNC are diazazirconacyclopentanes ( σ complexes), which are formed via an isomerization pathway. The effects of substituents on the isonitrile nitrogen atom in the main elementary reactions are also discussed.