Sterically Hindered Aromatic Compounds. VI. A Remote ε-Deuterium Kinetic Isotope Effect in the Solvolysis of Perdeutero-2,4,6-tri-tert-butylbenzyl Chloride

Abstract

. Can. J. Chem. 53, 3171 (1975).2,4,6-Tri-tert-butylbenzyl chloride deuterated at the three tert-butyl groups was synthesized. Conductimetric solvolysis studies of the normal and perdeutero-2,4,6-tri-tert-butylbenzyl chloride at 30.06 "C in 80% ethanol-water provides evidence for an inverse remote &-deuterium isotope effect, kH/kD = 0.873-0.874. Under the same conditions the a-deuterium isotope effect was kH/kmD = 1.166 per deuterium, indicative of limiting solvolytic behavior. The remote &-deuterium isotope effect for the perdeutero compound is discussed in terms of the inductive effect of deuterium and steric effects on the transition state conformation.