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Lactam synthesis via the intramolecular hydroamidation of alkynes catalyzed by palladium complexes
Nitin T Patil1, Zhibao Huo, Gan B Bajracharya
1Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
Abstract:
The palladium complexes catalyzed intramolecular hydroamidation reaction of amidoalkynes gives the corresponding lactams in good to high yields. For example, in the presence of 10 mol % of Pd(PPh3)4 and 20 mol % of PhCOOH, the reaction of the amidoalkyne 3a in 1,4-dioxane at 100 degrees C proceeded smoothly to give the corresponding lactam 4a in 92% yield.
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