To a solution of 3-hydroxy-8-oxo-5,6,7,8-tetrahydronaphthalene-2-carbonitrile from method II-6 (45 mg, 0.24 mmol) and 3-methoxyphenacyl bromide (60 mg, 0.26 mmol, 1.1 eq) in anhydrous N,N-dimethylformamide (2 mL) was added potassium carbonate (66 mg, 0.48 mmol, 2 eq). The reaction mixture was shaken at 90° C. for 17 h. The mixture was cooled to room temperature and poured into ethyl acetate and water. The aqueous layer was extracted with ethyl acetate twice. Combined the organic layers and evaporated in vacuo. The crude product was washed with methanol and gave 19 mg (24%) of 3-Amino-2-(3-methoxy-benzoyl)-7,8-dihydro-6H-naphtho[2,3-b]furan-5-one as a yellow solid. 1H-NMR (DMSO-d6) δ 8.72 (s, 1H), 7.68 to 7.42 (m, 5H), 7.18 to 7.14 (m, 1H). 6.33 (s, 1H), 3.84 (s, 3H), 3.07 (t, J=6.0 Hz, 2H), 2.65 (t, J=6.6 Hz, 2H), 2.50 (m, 2H); MS LC-MS (MH+=336.2); Rf=0.62, 50% ethyl acetate-hexane.
