Direct Reductive Amination of Camphor Using Iron Pentacarbonyl as Stoichiometric Reducing Agent: Features and Limitations

The method of direct reductive amination of camphor and fenchone was proposed. The most effective reducing agent is iron carbonyl. No ligands or solvents are needed. The stereochemistry of the corresponding products was determined by HMBC, HSQC, and NOESY spectra. The limitations of the method were shown. The reaction of camphor with primary amines led to exclusively exo product, while the reaction of fenchone led to exclusively endo product. The reaction of camphor with cyclic secondary amines led to the mixture of endo and exo isomers.