Palladium-Catalyzed C(sp³)-H Nitrooxylation of Aliphatic Carboxamides with Practical Oxidants

Here we report the palladium-catalyzed beta-C-(sp(3))-H nitrooxylation of aliphatic carboxamides using a modified quinoline auxiliary. Notably, Al-(NO3)(3)center dot 9H(2)O was used as a nitrate source as well as a practical oxidant. The 5-chloro-8-aminoquinoline auxiliary was nitrated in situ during the reaction, which may enhance its directing ability and help its removal. The reaction has a broad substrate scope with a variety of aliphatic carboxamides. The multiple substituted auxiliary can be easily removed and recovered. Two C-H-insertion palladacycle intermediates were isolated and characterized to elucidate the mechanism.