[CH3:1][O:2][C:3]1[CH:8]=[CH:7][CH:6]=[C:5]([NH2:9])[CH:4]=1.N([O-])=O.[Na+].O.O.[Sn](Cl)Cl.[C:19]1(=O)[CH2:24][CH2:23][CH2:22][C:21](=[O:25])[CH2:20]1.[OH-].[Na+]>O.Cl>[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:6]([C:20]3[C:21](=[O:25])[CH2:22][CH2:23][CH2:24][C:19]=3[NH:9]2)=[CH:7][CH:8]=1To a chilled mixture of m-anisidine (10 g, 81 mmol) in water (200 mL) and concentrated hydrochloric acid (25 mL) is added sodium nitrite (5.6 g, 81 mmol) dissolved in water (30 mL). The mixture is stirred at 5° C. for one h. To this is added tin (II) chloride dihydrate (36.6 g, 162 mmol) dissolved in concentrated hydrochloric acid (75 mL). The mixture is allowed to warm to room temperature and stirred for 1 h. 1,3 cyclohexanedione (9.1 g, 81 mmol) is added and the mixture stirred for 2 h. The mixture is slowly neutralized with 10% NaOH. Filtered solids and washed with water (500 mL). The solids are then slurried in acetonitrile (600 mL), filtered and washed with acetonitrile (200 mL). The filtrates are dried over anhydrous sodium sulfate, filtered and concentrated. The residue is refluxed in TFA (70 mL) for 18 h. The mixture is partitioned between water and CH2Cl2. The organic layer is separated and washed twice with water (200 mL). The organic layer is dried over anhydrous sodium sulfate, filtered, and concentrated. Ethyl acetate (100 mL) is added to the residue and the solids filtered to give 2.29 g (13%) of the title compound; IR (drift) 3156, 3118, 3073, 1620, 1583, 1501, 1470, 1451, 1288, 1196, 1178, 1153, 1142, 1107, 830 cm−1. 1H NMR (DMSO-d6) δ2.08, 2.7, 2.9, 3.8, 6.7, 6.9, 7.8; Anal. Calcd for C13H13NO2: C, 72.54; H, 6.09; N, 6.51. Found: C, 60.95; H, 5.18; N, 5.61.
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