HCID 178498493, compound → HCID 178524584, compound

Participants

Reaction Steps

A mixture of 2.0 g. (0.0065 mole) of methyl 1-hydroxy[1]benzothieno[3,2-f]quinoline-3-carboxylate (about 90 percent pure) in N,N-dimethyl formamide is heated to its reflux temperature, and several drops of 10 percent aqueous hydrochloric acid are added every fifteen minutes for 2 hours. The resulting yellow solid is separated by filtration to provide 1-hydroxy[1]benzothieno[3,2-f]quinoline-3-carboxylic acid, m.p. >285° C. (dec.). Analysis: Calculated for C16H9NO3S: %C, 65.1; %H, 3.1; %N, 4.7; Found: %C, 64.9; %H, 2.9; %N, 4.8. Purity is greater than 98 percent according to nuclear magnetic resonance spectral analysis.

Provenance & Evidence