Palladium-Catalyzed Intramolecular Allylic Amidation via Decarboxylative Aromatization: Synthesis of N-Allyl-N-aryl
Tzu-Lun Liu1, Meng-Li Jhou1, Cheng-En Hsieh1
1Department of Applied Chemistry, National University of Kaohsiung, 700, Kaohsiung University Road, Nanzih District, 81148 Kaohsiung, Taiwan.
Abstract:
A protocol in the preparation of functionalized N-allyl-N-aryl sulfonamides via palladium-catalyzed intramolecular decarboxylative N-allylation reaction is presented. The alkylated 2,5-cyclohexadienyl ketoesters reacted with arylsulfonamides in the presence of titanium tetrachloride and pyridine, which allows the formation of alkylated 2,5-cyclohexadienyl sulfonyl iminoesters which then undergo a palladium-catalyzed intramolecular allylic amidation through decarboxylative aromatization to provide functionalized N-allyl-N-aryl sulfonamides. This allylation protocol proceeds with good regioselectivity. Moreover, we have also shown that N-allyl-N-aryl sulfonamide can be transformed into 4-aryl-1,2,3,4-tetrahydroquinoline and nitrogen-containing β-hydroxysulfide bioactives.
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