Herein, radical addition to the C[dbnd]N bond in hydrazone derivatives of α-ketoesters under “on-water” conditions has been described. The present method provides a route to synthesize α,α-dialkyl α-amino esters, which are difficult to obtain using other methods because of their intrinsically low activity. The radical addition reaction is more efficient when performed under “on-water” conditions than when performed in an organic solvent, showing the prominent solvent effect of water. In the present process, the (Z)-hydrazone derivatives of α-ketoesters show higher reactivity than their corresponding (E)-hydrazones. The process provides tin-free, green reaction conditions.
Bibliographical noteFunding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), South Korea funded by the Ministry of Education ( NRF2016R1D1A3B03932348 ). Appendix A
All Science Journal Classification (ASJC) codes
- Drug Discovery
- Organic Chemistry