Formaldehyde → 2-(4-Chlorophenylamino)naphtho[2,3-b]furan-4,9-dione

Participants

Reaction Steps

4-chlorobenzenamine 12.7 g (0.1 mol), and 470 mg BnEt3NCl was suspended in the mixture of 200 ml DCM, 200 ml CH3C1 and 200 ml 50% KOH (aq.), then was stirred at room temperature for 2 h. The organic phase was separated, washed with water (500 ml), dried with Na2SO4 and concentrated to afford yellow oil, which was purified by chromatography; 1-chloro-4-isocyanobenzene 500 mg, 2-hydroxynaphthalene-1,4-dione 635 mg (1.0 eq) and Paraformaldehyde 109 mg (1.0 eq) was dissolved in 30 ml toluene, stirred and refluxed under N2 for 4 h. After removing all solvents under reduced pressure, the residue was purified by chromatography to afford 2-(4-chlorophenylamino)naphtho[2,3-b]furan-4,9-dione as black solid. 1H NMR (300 MHz, DMSO) δ6.39 (s, 1H); 7.24˜7.29 (m, 2H); 7.41˜7.43 (dd, 2H); 7.54 (br, 1H); 7.69˜7.73 (t, 1H); 7.78˜7.82 (t, 1H); 8.13˜8.17 (t, 3H) ppm. MS-ESI: cal. 323; found: 346 (M+Na).

Provenance & Evidence