Synthesis 2008(9): 1467-1478  
DOI: 10.1055/s-2008-1067017
FEATUREARTICLE
© Georg Thieme Verlag Stuttgart · New York

H-D Exchange Reaction Taking Advantage of the Synergistic Effect of Heterogeneous Palladium and Platinum Mixed Catalyst

Nobuhiro Itoa, Tsutomu Watahikia, Tsuneaki Maesawaa, Tomohiro Maegawab, Hironao Sajiki*b
a Chemical Products Research Laboratories, Wako Pure Chemical Industries, Ltd., 1633 Matoba, Kawagoe 350-1101, Japan
Fax: +81(49)2337953;
b Laboratories of Medicinal Chemistry, Gifu Pharmaceutical University, 5-6-1 Mitahora-higashi, Gifu 502-8585, Japan
Fax: +81(58)2375979; e-Mail: sajiki@gifu-pu.ac.jp;
Further Information

Publication History

Received 12 February 2008
Publication Date:
11 April 2008 (online)

Abstract

An effective and applicable deuteration method for alkyl-substituted aromatic compounds using a heterogeneous Pd/C and Pt/C mixed catalyst in deuterium oxide in the presence of a small amount of hydrogen gas was developed. Mixing a heterogeneous palladium and platinum catalyst provides an interesting synergistic effect in the H-D exchange reaction and leads to full H-D exchange results even on sterically hindered sites, which indicated only low-deuterium efficiencies when either Pd/C or Pt/C were used independently as a catalyst. We investigated the synergistic effect using a variety of substrates and proved the broad generality of the heterogeneous Pd-Pt-D2O-H2 system in the H-D exchange reaction. Furthermore, this system could be applied to a multigram scale synthesis of useful deuterium-labeled compounds, such as deuterium-labeled bis-aniline derivatives as raw materials for polyimides, aryl iodides as synthetic building blocks, and biologically active compounds.