Chemoselective aryllithium addition to an α-cyanoester under continuous-flow conditions
Mohmmad S Qenawy1, Xianzhu Zhong1, Aiichiro Nagaki1
1Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10-jo, Nishi 8-chome, Kita-ku, Sapporo 060-0810, Japan. nagaki@sci.hokudai.ac.jp.
Abstract:
Chemoselective addition of aryllithium reagents to an α-cyanoester was achieved under continuous-flow conditions, enabling selective ester-to-ketone conversion while retaining the nitrile group. Optimized mixing, temperature, and residence time improved product yield and selectivity compared with batch conditions. The method accommodated diverse aryllithium nucleophiles, affording products in up to 92% yield, and enabled multistage flow synthesis using a challenging aryllithium intermediate in 69% yield.
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