Published March 15, 1979 | Version v1
Journal article

Secondary α-hydrogen kinetic isotope effects in nucleophilic additions to ferrocenyl-stabilised carbocations

  • 1. California Univ., Santa Barbara (USA)

Description

The secondary α-hydrogen kinetic isotope effects upon the solvolyses of Fc2C+H (1a) and p-MeOC6H4C+HFc (1b) (Fc = ferrocenyl) in H2O, H2O-MeCN, and H2O-MeOH (ksub(f)sup(H)/ksub(f)sup(D) = ca. 0.9), and upon the acid heterolyses of the corresponding alcohols (ksub(r)sup(H)/ksub (r)sup(D) = ca. 1.1), suggest that there is appreciable C....O bond formation in the transition state for carbocation solvolysis; for additions of HO-, N3-, and BH4- to (1a), ksub(f)sup(H)/ksub(f)sup(D) = ca. 1.0, indicating 'early' carbocation-like transition states for these reactions, whereas intermediate values (ksub(f)sup(H)/ksub(f)sup(D) = ca. 0.96) are found for additions of primary amines. (author)

Additional details

Publishing Information

Journal Title
J. Chem. Soc. (London), Chem. Commun.
Journal Issue
no.6
Series
J. Chem. Soc. (London), Chem. Commun.