The α-secondary isotope effect in the 1,2C rearrangement of cyclopropylchlorocarbene

Article abstract of DOI:10.1016/S0040-4039(00)61718-5

The experimental α-secondary kinetic isotope effect for the rearrangement of (2,2-dideuteriocylopropyl)chlorocarbene, 2-d₂, to chlorocyclobutenes, 4 and 5, is k_H/k_D = 1.20 at 21° C. The corresponding value calculated by ab initio electronic structure methods is 1.12. The isotope effect very largely originates in hybridization changes at the migrating carbon atom.