Palladium(II)-Catalyzed Direct Carboxylation of Alkenyl C-H Bonds with CO2
Kota Sasano, Jun Takaya and Nobuharu Iwasawa*
*Department of Chemistry, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8551, Japan, Email: niwasawachem.titech.ac.jp
K. Sasano, J. Takaya, N. Iwasawa, J. Am. Chem. Soc., 2013, 135, 10954-10957.
DOI: 10.1021/ja405503y (free Supporting Information)
A direct carboxylation of alkenyl C-H bonds of 2-hydroxystyrenes in the presence of a catalytic amount of Pd(OAc)2 and Cs2CO3 as base under atmospheric pressure of CO2 afforded coumarins in good yield. The reaction undergoes a reversible nucleophilic addition of the alkenylpalladium intermediate to CO2.
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