Theoretical insights into the reaction of Cp*(Cl)Hf(diene) with isonitriles

摘要: The migratory insertion of isonitriles into a metal–C bond is potentially important method for C–C construction in organic and pharmaceutical syntheses. In this context, the reaction mechanism Cp*(Cl)Hf(diene) (Cp* = pentamethylcyclopentadienyl) with was studied using density functional theory calculations. Hf-imido complexes α-methylene cyclopentenimines are confirmed products N-tert-butyl- or N-1-adamantyl-substituted isonitriles. They also thermodynamically favored N-2,6-dimethylphenyl (Ar)-substituted β-H elimination pathway responsible formation cyclopentenimines. Its elementary reactions include isomerization Cp*(Cl)Hf(diene), first isonitrile Hf–C bond, reductive elimination, second Hf–H coupling, addition fragmentation six-membered hafnacycle. For methyl-, ethyl-, Ar-substituted isonitriles, kinetically diazahafnacyclopentanes (“σ complexes”). These formed via an that comprises Hf complex, CN bond. effects different substituents on nitrogen main discussed.