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FeCl3 as an Ion-Pairing Lewis Acid Catalyst. Formation of Highly Lewis Acidic FeCl2+ and Thermodynamically Stable FeCl4- To Catalyze the Aza-Diels-Alder Reaction with High Turnover Frequency

Rei Tomifuji, Kazuki Maeda, Toshifumi Takahashi, Takuya Kurahashi*, Seijiro Matsubara*

*Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan, Email:,

R. Tomifuji, J. Maeda, T. Takahashi, T. Kurahashi, S. Matsubara, Org. Lett., 2018, 20, 7474-7477.

DOI: 10.1021/acs.orglett.8b03249

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The ion-paired Lewis acid [FeCl2]+[FeCl4]- generated by the in situ disproportionation of FeCl3 catalyzes an aza-Diels-Alder reaction of nonactivated dienes and imines.

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Key Words

Diels-Alder reaction, 1,2,3,6-Tetrahydropyridines

ID: J54-Y2018