3-hydroxy-4-propoxybenzaldehyde

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: An amount of 3-hydroxy-4-propoxybenzaldehyde (150 mg, 0.83 mmol) is added pyridine (4.0 ml) at room temperature, followed by addition of methoxylamine hydrogen chloride (101.2 mg, 1.2 mmol). The mixture is stirred at ambient temperature for 24 h, and 4 mL of water is added. After the solvents were evaporated, the residue is dissolved 8 mL of anhydrous ether, washed successively with 2 mL of aqueous sodium bicarbonate, 2 mL of sodium bisulfite, and 2 mL of brine. Dried over magnesium sulfate, evaporated to give a yellow solid (210 mg). MS (ESI) m/z 210.5 (M+1) After the solvents were evaporated the residue is dissolved 8 mL of anhydrous ether washed successively with 2 mL of aqueous sodium bicarbonate, 2 mL of sodium bisulfite, and 2 mL of brine Dried over magnesium sulfate evaporated

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

Procedure: A mixture of 3-hydroxy-4-propoxybenzaldehyde (0.8 g, 4.4 mmol), 3,4,5-trimethoxyacetophenone (0.934 mg, 4.4 mmol) and 50% w/v of aqueous sodium hydroxide (7.0 ml, 0.089 mol) in methanol (10 ml) at room temperature for 18 h. The orange solid isolated by filtration was washed sequentially with cold methanol and ether and finally dried in a vacuum dessicator. Purification was achieved using column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) which gave 0.995 g (60%) of a yellow solid. 1H-NMR (CDCl3) δ 7.7 (d, 1H), 7.2 (m, 4H), 7.1 (dd, 3H), 6.9 (d, 1H), 5.7 (s, 1H), 4.1 (t, 2H), 3.9 (s×2, 9H), 1.9 (m, 2H), 1.1 (t, 3H). 13C-NMR (CDCl3) δ 189.1, 153.1, 148.3, 146.0, 144.7, 142.4, 133.7, 128.4, 122.9, 119.8, 112.7, 111.4, 106.1, 70.6, 60.9, 56.4, 22.4, 10.4. Mass Spectrum m/e (M+1) 373. Anal. Calcd. for C21H24O6: C, 67.73; H, 6.5. Found C, 68.01; H, 6.72. The orange solid isolated by filtration was washed sequentially with cold methanol and ether finally dried in a vacuum dessicator Purification

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

Procedure: Anhydrous potassium carbonate (5.9 g, 0.043 mmol) and sodium iodide (0.434 g, 4.3 mmol) were added to 3,4-dihydroxybenzaldehyde (4.0 g, 28.9 mmol), in butanone (100 ml), at room temperature. The reaction was stirred for 10 min after which propyl bromide (2.628 ml, 28.9 mmol) was added dropwise and the reaction was refluxed for 3 h. The reaction mixture was diluted with water and the product was extracted with dichloromethane (3×50 ml), the combined organic layers were dried over magnesium sulphate and reduced in vacuo. Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) afforded 1.21 g (23.3%) of 3-hydroxy-4-propoxybenzaldehyde as an off-white solid. was added dropwise the reaction was refluxed for 3 h the product was extracted with dichloromethane (3×50 ml) the combined organic layers were dried over magnesium sulphate Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate)

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

Procedure: A mixture of 3-hydroxy-4-propoxybenzaldehyde (0.8 g, 4.4 mmol), 3,4,5-trimethoxyacetophenone (0.934 mg, 4.4 mmol) and 50% w/v of aqueous sodium hydroxide (7.0 ml, 0.089 mol) in methanol (10 ml) at room temperature for 18 h. The orange solid isolated by filtration was washed sequentially with cold methanol and ether and finally dried in a vacuum dessicator. Purification was achieved using column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) which gave 0.995 g (60%) of a yellow solid. 1H-NMR (CDCl3) δ 7.7 (d, 1H), 7.2 (m, 4H), 7.1 (dd, 3H), 6.9 (d, 1H), 5.7 (s, 1H), 4.1 (t, 2H), 3.9 (s×2, 9H), 1.9 (m, 2H), 1.1 (t, 3H). 13C-NMR (CDCl3) δ 189.1, 153.1, 148.3, 146.0, 144.7, 142.4, 133.7, 128.4, 122.9, 119.8, 112.7, 111.4, 106.1, 70.6, 60.9, 56.4, 22.4, 10.4. Mass Spectrum m/e (M+1) 373. Anal. Calcd. for C21H24O6: C, 67.73; H, 6.5. Found C, 68.01; H, 6.72. The orange solid isolated by filtration was washed sequentially with cold methanol and ether finally dried in a vacuum dessicator Purification

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

Procedure: A mixture of 3-hydroxy-4-propoxybenzaldehyde (0.4 g, 2.1 mmol), 3,5-dimethoxyacetophenone (0.371 mg, 2.1 mmol) and 50% w/v of aqueous sodium hydroxide (3.3 ml, 0.206 mol) in methanol (10 ml) at room temperature for 18 h. The yellow solid that precipitated was filtered and sequentially washed with cold methanol and ether and finally dried in a vacuum dessicator. Purification was achieved using column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) which gave 0.95 g (19%) of a yellow solid. 1H-NMR (CDCl3) δ 7.7 (d, 1H), 7.3 (m, 2H), 7.1 (d, 3H), 6.8 (d, 1H), 6.6 (d, 1H), 5.7 (s, 1H), 4.1 (t, 2H), 3.9 (s, 6H), 1.9 (m, 2H), 1.0 (t, 3H). 13C-NMR (CDCl3) δ 160.9, 146.0, 144.9, 128.4, 122.6, 120.2, 112.9, 106.2, 104.9, 70.6, 55.6, 22.4, 10.4. Mass Spectrum m/e (M+1) 343. Anal. Calcd. for C20H22O5: C, 70.16; H, 6.48. Found C, 70.08; H, 6.38. The yellow solid that precipitated was filtered sequentially washed with cold methanol and ether finally dried in a vacuum dessicator Purification

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

Procedure: Anhydrous potassium carbonate (1.5 g, 10.8 mmol) and sodium iodide (0.108 g, 0.72 mmol) were added to 3,4-dihydroxybenzaldehyde (1.0 g, 7.2 mmol), in butanone (50 ml), at room temperature. The reaction was stirred for 10 min after which propyl bromide (0.657 ml, 7.2 mmol) was added dropwise and the reaction was refluxed for 3 h. The reaction mixture was diluted with water and the product was extracted with dichloromethane (3×25 ml), the combined organic layers were dried over magnesium sulphate and reduced in vacuo. Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) afforded 0.248 g (22%) of 3-hydroxy-4-propoxybenzaldehyde as an off-white solid. was added dropwise the reaction was refluxed for 3 h the product was extracted with dichloromethane (3×25 ml) the combined organic layers were dried over magnesium sulphate Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate)

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

Procedure: Anhydrous potassium carbonate (1.5 g, 10.8 mmol) and sodium iodide (0.108 g, 0.72 mmol) were added to 3,4-dihydroxybenzaldehyde (1.0 g, 7.2 mmol), in butanone (50 ml), at room temperature. The reaction was stirred for 10 min after which propyl bromide (0.657 ml, 7.2 mmol) was added dropwise and the reaction was refluxed for 3 h. The reaction mixture was diluted with water and the product was extracted with dichloromethane (3×25 ml), the combined organic layers were dried over magnesium sulphate and reduced in vacuo. Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) afforded 0.248 g (22%) of 3-hydroxy-4-propoxybenzaldehyde as an off-white solid. was added dropwise the reaction was refluxed for 3 h the product was extracted with dichloromethane (3×25 ml) the combined organic layers were dried over magnesium sulphate Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate)