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Dual Studies on a Hydrogen-Deuterium Exchange of Resorcinol and the Subsequent Kinetic Isotope Effect.

ABSTRACT: An efficient laboratory experiment has been developed for undergraduate students to conduct hydrogen-deuterium (H-D) exchange of resorcinol by electrophilic aromatic substitution using D₂O and a catalytic amount of H₂SO₄. The resulting labeled product is characterized by ¹H NMR. Students also visualize a significant kinetic isotope effect (k_H/k_D ? 3 to 4) by adding iodine tincture to solutions of unlabeled resorcinol and the H-D exchange product. This method is highly adaptable to fit a target audience and has been successfully implemented in a pedagogical capacity with second-year introductory organic chemistry students as part of their laboratory curriculum. It was also adapted for students at the advanced high school level.

SUBMITTER: Giles R

PROVIDER: S-EPMC4131703 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Dual Studies on a Hydrogen-Deuterium Exchange of Resorcinol and the Subsequent Kinetic Isotope Effect.

Giles Richard R Kim Iris I Chao Weyjuin Eric WE Moore Jennifer J Jung Kyung Woon KW

Journal of chemical education 20140801 8

An efficient laboratory experiment has been developed for undergraduate students to conduct hydrogen-deuterium (H-D) exchange of resorcinol by electrophilic aromatic substitution using D2O and a catalytic amount of H2SO4. The resulting labeled product is characterized by 1H NMR. Students also visualize a significant kinetic isotope effect (kH/kD ≈ 3 to 4) by adding iodine tincture to solutions of unlabeled resorcinol ...[more]

PMID: 25132687

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