Kinetic isotope effects in the reduction of 2- and 3-alkyl-substituted-indanone-(tricarbonyl)chromium complexes by NaBH4 and NaBD4. Evidence for displacement of the transition state depending on the substrate

Abstract

The kinetic, primary, H–D isotope effects, measured when 2- and 3- alkyl-substituted-indanone-(tricarbonyl)chromium complexes are reduced with NaBH₄ and NaBD₄, exhibit significant variations of k_H/k_D values depending on the degree of steric hindrance around the ketone groups; this suggests that displacements of the transition states are involved in this type of reaction.