Asymmetric Cycloaddition Reactions of Aryne Intermediates with a Chiral Carbon-Carbon Axis: Syntheses of Axially
Tomoyuki Yoshimura1, Ken-Ichi Onda1, Jun-Ichi Matsuo1
1Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Abstract:
An asymmetric synthesis via an axially chiral arylaryne intermediate was developed. A cycloaddition reaction with various arynophiles was used to obtain chiral biaryl compounds while preserving the enantiomeric excess (ee) of a precursor even though the reaction proceeds through an arylaryne intermediate, whose ee decreases on a time-dependent basis. High chiral transfer from a precursor to a product was observed not only at low temperature (-78 °C) but also at room temperature.
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