Nickel-Catalyzed Double Carboxylation of Alkynes Employing Carbon Dioxide
Tetsuaki Fujihara, Yuichiro Horimoto, Taiga Mizoe, Fareed Bhasha Sayyed, Yosuke Tani, Jun Terao, Shigeyoshi Sakaki* and Yasushi Tsuji*
*Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510; Kyoto University, Nishihiraki-Cho-34-4, Sakyo-ku, Kyoto 606-8103, Japan, Email: sakaki.shigeyoshi.47est.kyoto-u.ac.jp, ytsujiscl.kyoto-u.ac.jp
T. Fujihara, Y. Horimoto, T. Mizoe, F. B. Sayyed, Y. Tani, J. Terao, S. Sakaki, S. Tsuji, Org. Lett., 2014, 16, 4960-4963.
DOI: 10.1021/ol502538r (free Supporting Information)
A nickel-catalyzed double carboxylation of internal alkynes proceeds under CO2 (1 atm) at room temperature in the presence of Zn powder as a reducing reagent and MgBr2 as an indispensable additive. Various internal alkynes could be converted to the corresponding maleic anhydrides in good to high yields.
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