Enantioselective fluorination of organic molecules. I. Synthetic studies of the agents for electrophilic, enantioselective fluorination of carbanions.

Y Takeuchi, A Satoh, T Suzuki, A Kameda, M Dohrin, T Satoh, T Koizumi, K L Kirk

Index: Chem. Pharm. Bull. 45(6) , 1085-8, (1997)

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Abstract

In order to develop novel methods for electrophilic and enantioselective fluorination of active methine compounds, preliminary experiments were carried out. The N-tosyl derivative 5 obtained from D-phenylglycine was fluorinated with FClO3 or diluted F2 gas to give the N-fluoro-N-tosyl derivative 6. N-tosyl- or N-mesyl-(S)-alpha-phenethylamine 7 or 8 was subjected to FClO3 fluorination to produce the corresponding N-fluoro derivative, 10 or 11, respectively. Enantioselective fluorination of some methine compounds was attempted employing the above N-fluoro agents. Best result was obtained when 2-benzyl-1-tetralone/KHMDS was treated with 10 to produce the fluorinated tetralone 17 in 53% yield with enantiomeric excess (ee) of 48%.