Catalytic Amination of β-(Hetero)arylethyl Ethers by Phosphazene Base t-Bu-P4
Masanori Shigeno1, Ryutaro Nakamura1, Kazutoshi Hayashi1
1Department of Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba, Sendai, 980-8578, Japan.
Abstract:
We describe the catalytic amination of β-(hetero)arylethyl ethers with amines using the organic superbase t-Bu-P4 to obtain β-(hetero)arylethylamines. The reaction has a broad substrate scope and allows the transformations of electron-deficient and electron-neutral β-(hetero)arylethyl ethers with various amines including pyrrole, N-alkylaniline, diphenylamine, aniline, indole, and indoline derivatives. Mechanistic studies indicate a two-reaction pathway of MeOH elimination from the substrate to form a (hetero)arylalkene followed by the hydroamination of the alkene.
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