Anthranilic Acid → HCID 66753771, compound

Participants

Reaction Steps

Analogously to the method described by Gonsalves et al. (Tetrahedron 1992, 48, 6821) a solution of 3.90 g of ethyl 5,6,7,8-tetrahydro-benzo[1,2,4]triazin-3-carboxylate (Sagi et al., Heterocycles 1989, 29, 2253) in 20 ml dioxane is refluxed. Then 8.22 g of anthranilic acid and 7.02 g of isoamylnitrite, in each case dissolved in 20 ml dioxane, are simultaneously added dropwise within 25 minutes by means of two dropping funnels. The reaction mixture is refluxed for a further 30 minutes. For working up the cooled deep-brown reaction solution is diluted with 150 ml diethyl ether, washed with 100 ml of 2 N sodium hydroxide solution and with water, dried over magnesium sulphate and evaporated down. The brown, oily flask residue is chromatographed through a silica gel column with ethyl acetate/petroleum ether (20:80 to 50:50) as eluant. The product obtained is still somewhat contaminated, but is reacted further without any more purification.

Provenance & Evidence