2',3'-DIHYDROXYACETOPHENONE

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prepared by reacting 1-(2,3-dihydroxy-phenyl)-ethanone with 1,2-dibromoethane in the presence of potassium carbonate in N,N-dimethylformamide at 100° C. Prepared at 100° C.

Conditions: temp:110.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In the solution of 220 g(2 mol) of catechol in 500 ml of acetic acid, 102 g(1 mol) of acetic anhydride was drop-added for one hour while agitating the solution at 110° C. The mixture was maintained at 110° C. for two hours, and diethylene glycol dibutyl ether was distilled under vacuum. 1 Liter of toluene was added to the reaction mixture and cooled to 0° C. and then the unreacted excess hydroquinone was filtered and collected (recovered amount: 110 g, recycled without any purification process). A desired mono acetyl catechol was obtained by evaporating the residue in vacuum. (Yield: 149.0 g(98%). mp: oil. 1H-NMR(200 MHz, CDCl3, ppm) 2.33(s, 3H), 5.81 (br, 1H), 6.83-7.18 (m, 4H). The mixture was maintained at 110° C. for two hours diethylene glycol dibutyl ether was distilled under vacuum 1 Liter of toluene was added to the reaction mixture cooled to 0° C. the unreacted excess hydroquinone was filtered collected ( recovered amount

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prepared by reacting 1-(2,3-dihydroxy-phenyl)-ethanone with 1,2-dibromoethane in the presence of potassium carbonate in N,N-dimethylformamide at 100° C. Prepared at 100° C.

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of acetovanillone (33) (4.70 g, 28.3 mmol) in MeCN (60 mL) was added K2CO3 (8.05 g, 58.3 mmol) and KI (0.20 g, 1.2 mmol). The mixture was stirred under N2 atmosphere and benzyl bromide (34) (4.0 mL, 34 mmol) was added dropwise. The reaction mixture was reflux for 24 h and then cooled to 25° C., then resulting precipitate was filtered off. The filtrate was evaporated and purified by column chromatography (SiO2, n-hexane: CH2Cl2=1:2) to give 30. White solid; yield: 70.3%; mp 87-88° C.; 1H-NMR (CDCl3. 200 MHz): δ 2.51 (s, 3H), 3.91 (s, 3H), 5.20 (s, 2H), 6.86 (d, J=8.2 Hz, 1H), 7.21-7.55 (m, 7H); 13C-NMR (CDCl3, 50 MHz): δ 26.19, 56.05, 70.79, 110.53, 112.13, 123.07, 127.18, 128.10, 128.68, 130.72, 136.28, 149.49, 152.41, 196.80; Anal. calcd for C16H16O3: C, 74.98; H, 6.29. Found: C, 75.02; H, 6.25. The reaction mixture was reflux for 24 h resulting precipitate was filtered off The filtrate was evaporated purified by column chromatography (SiO2, n-hexane: CH2Cl2=1:2)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1,2-dihydroxybenzene (28)(2.0 g, 18.2 mmol) in AcOH (1.3 g, 21.7 mmol) was added boron trifluoride diethyl ether (98% in Et2O, 2 mL). The mixture was reacted under microwave irradiation (300 W) for 1.5 min and then cooled to 25° C. The reaction mixture was dissolved in dichoromethane (10 mL) and H2O (about 20 mL). The organic lay was washed with 10% NaHCO3 and then with water, dried over MgSO4 and concentrated. The crude was purified by column chromatography (SiO2, CH2Cl2) to give 30. Yellow solid; yield: 10.4%; mp 76-77° C.; 1H-NMR (CDCl3,200 MHz): δ 2.58 (s, 3H), 5.79 (s, 1H), 6.79 (t, J=8.0 Hz, 1H), 7.10 (d, J=8.0 Hz, 1H), 7.26 (d, J=8.0 Hz, 1H), 12.45 (s, 1H); 13C-NMR (CDCl3, 50 MHz): δ 26.73, 118.79, 119.52, 120.39, 121.44, 145.40, 149.50, 205.08; Anal. calcd for C8H8O3: C, 63.15; H, 5.30. Found: C, 63.10; H, 5.33. The mixture was reacted under microwave irradiation (300 W) for 1.5 min The organic lay was washed with 10% NaHCO3 with water, dried over MgSO4 concentrated The crude was purified by column chromatography (SiO2, CH2Cl2)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6-Amino-2,3-dimethoxyacetophenone (2) was also prepared according to published methods. The starting catechol (28) was acetylated, in microwave oven set at 300 Watt power, by reacting with mixture of acetic acid (29) and BF3. Et2O to yield 2,3-dihydroxyacetophenone (30) which was further reacted with diiodomethane in DMF, in the presence of K2CO3, to afford 2,3-methylenedioxyacetophenone (31). Subsequent nitration of compound 31 with 70% HNO3 afforded 2,3-methylenedioxy-6-nitroacetophenone (32). Without purification, compounds 32 was hydrogenated, and purified with column chromatography to provide 6-amino-2,3-methylenedioxyacetophenone (2).10 Another published method was followed in preparation of 6-amino-3-methoxy-4-benzyloxyacetophenone (3). First, the benzylation of the starting acetovanillone (33) with benzylbromide (34) gave 4-benzyloxy-3-methoxyacetophenone (35) which was nitrated to yield 4-benzyloxy-3-methoxy-6-nitroacetophenone (36).11 The so-obtained compound 36 was reduced with SnCl2 to afford compound 3.

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of acetovanillone (33) (4.70 g, 28.3 mmol) in MeCN (60 mL) was added K2CO3 (8.05 g, 58.3 mmol) and KI (0.20 g, 1.2 mmol). The mixture was stirred under N2 atmosphere and benzyl bromide (34) (4.0 mL, 34 mmol) was added dropwise. The reaction mixture was reflux for 24 h and then cooled to 25° C., then resulting precipitate was filtered off. The filtrate was evaporated and purified by column chromatography (SiO2, n-hexane: CH2Cl2=1:2) to give 30. White solid; yield: 70.3%; mp 87-88° C.; 1H-NMR (CDCl3. 200 MHz): δ 2.51 (s, 3H), 3.91 (s, 3H), 5.20 (s, 2H), 6.86 (d, J=8.2 Hz, 1H), 7.21-7.55 (m, 7H); 13C-NMR (CDCl3, 50 MHz): δ 26.19, 56.05, 70.79, 110.53, 112.13, 123.07, 127.18, 128.10, 128.68, 130.72, 136.28, 149.49, 152.41, 196.80; Anal. calcd for C16H16O3: C, 74.98; H, 6.29. Found: C, 75.02; H, 6.25. The reaction mixture was reflux for 24 h resulting precipitate was filtered off The filtrate was evaporated purified by column chromatography (SiO2, n-hexane: CH2Cl2=1:2)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 1,2-dihydroxybenzene (28)(2.0 g, 18.2 mmol) in AcOH (1.3 g, 21.7 mmol) was added boron trifluoride diethyl ether (98% in Et2O, 2 mL). The mixture was reacted under microwave irradiation (300 W) for 1.5 min and then cooled to 25° C. The reaction mixture was dissolved in dichoromethane (10 mL) and H2O (about 20 mL). The organic lay was washed with 10% NaHCO3 and then with water, dried over MgSO4 and concentrated. The crude was purified by column chromatography (SiO2, CH2Cl2) to give 30. Yellow solid; yield: 10.4%; mp 76-77° C.; 1H-NMR (CDCl3,200 MHz): δ 2.58 (s, 3H), 5.79 (s, 1H), 6.79 (t, J=8.0 Hz, 1H), 7.10 (d, J=8.0 Hz, 1H), 7.26 (d, J=8.0 Hz, 1H), 12.45 (s, 1H); 13C-NMR (CDCl3, 50 MHz): δ 26.73, 118.79, 119.52, 120.39, 121.44, 145.40, 149.50, 205.08; Anal. calcd for C8H8O3: C, 63.15; H, 5.30. Found: C, 63.10; H, 5.33. The mixture was reacted under microwave irradiation (300 W) for 1.5 min The organic lay was washed with 10% NaHCO3 with water, dried over MgSO4 concentrated The crude was purified by column chromatography (SiO2, CH2Cl2)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 6-Amino-2,3-dimethoxyacetophenone (2) was also prepared according to published methods. The starting catechol (28) was acetylated, in microwave oven set at 300 Watt power, by reacting with mixture of acetic acid (29) and BF3. Et2O to yield 2,3-dihydroxyacetophenone (30) which was further reacted with diiodomethane in DMF, in the presence of K2CO3, to afford 2,3-methylenedioxyacetophenone (31). Subsequent nitration of compound 31 with 70% HNO3 afforded 2,3-methylenedioxy-6-nitroacetophenone (32). Without purification, compounds 32 was hydrogenated, and purified with column chromatography to provide 6-amino-2,3-methylenedioxyacetophenone (2).10 Another published method was followed in preparation of 6-amino-3-methoxy-4-benzyloxyacetophenone (3). First, the benzylation of the starting acetovanillone (33) with benzylbromide (34) gave 4-benzyloxy-3-methoxyacetophenone (35) which was nitrated to yield 4-benzyloxy-3-methoxy-6-nitroacetophenone (36).11 The so-obtained compound 36 was reduced with SnCl2 to afford compound 3.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prepared by reacting 1-(2,3-dihydroxy-phenyl)-ethanone with 1,2-dibromoethane in the presence of potassium carbonate in N,N-dimethylformamide at 100° C. Prepared at 100° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prepared by reacting 1-(2,3-dihydroxy-phenyl)-ethanone with 1,2-dibromoethane in the presence of potassium carbonate in N,N-dimethylformamide at 100° C. Prepared at 100° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prepared by reacting 1-(2,3-dihydroxy-phenyl)-ethanone with 1,2-dibromoethane in the presence of potassium carbonate in N,N-dimethylformamide at 100° C. Prepared at 100° C.