Synthesis
General procedure for the synthesis of 7-hydroxyquinolin-2(1H)-one from N-(3-methoxyphenyl)cinnamamide: Aluminum trichloride (3.16 g, 23.69 mmol) was added batchwise to a suspension of chlorobenzene (30 mL) of compound 3 (1 g, 3.95 mmol) in an ice bath. The reaction mixture was gradually warmed up to 120 °C and kept at reflux for 3 hours. The reaction process was monitored by thin layer chromatography (TLC). After completion of the reaction, the reaction mixture was concentrated to dryness under reduced pressure and the residue was purified by silica gel column chromatography to afford compound 4 in 54% yield.
References
[1] Synthesis, 1997, # 1, p. 87 - 90
[2] Tetrahedron Letters, 1999, vol. 40, # 24, p. 4505 - 4506
[3] Journal of Medicinal Chemistry, 2015, vol. 58, # 14, p. 5561 - 5578
[4] Patent: CN108101926, 2018, A. Location in patent: Paragraph 0033; 0034; 0035
[5] Patent: WO2008/24481, 2008, A2. Location in patent: Page/Page column 32
