2-Bromo-3-hydroxy-4-methoxybenzaldehyde

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: Isovanillin (76.1 g, 0.5 m) was suspended in 750 ml of chloroform. Bromine (27.3 ml, 0.5 m) in 200 ml of chloroform was added at 0° slowly. Water was added to give the desired 2-bromo-3-hydroxy-4-methoxybenzaldehyde, m.p. 197°-203°.

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

Procedure: Isovanillin (76.1 g, 0.5 m) was suspended in 750 ml of chloroform. Bromine (27.3 ml, 0.5 m) in 200 ml of chloroform was added at 0° slowly. Water was added to give the desired 2-bromo-3-hydroxy-4-methoxybenzaldehyde, m.p. 197°-203°.

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

Procedure: Isovanillin (76.1 g, 0.5 m) was suspended in 750 ml of chloroform. Bromine (27.3 ml, 0.5 m) in 200 ml of chloroform was added at 0° slowly. Water was added to give the desired 2-bromo-3-hydroxy-4-methoxybenzaldehyde, m.p. 197°-203°.

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

Procedure: Diethyl azodicarboxylate (2.7 ml) was dropwise added to a mixture of 2-bromo-3-hydroxy-4-methoxy-benzaldehyde (4.0 g), THF (80 ml), 2-cyclohexen-1-ol (1.2 ml), and triphenylphosphine (4.5 g) under ice-cooling, followed by stirring at room temperature for 2 hours. The mixture was poured into water followed by extraction with ether. The organic layer was washed with a 1N aqueous solution of sodium hydroxide and with a saturated saline, and dried over sodium sulfate. The solvent was distilled off, and the residue was purified by column chromatography (hexane:ethyl acetate=10:1 and 5:1) to give Compound IIn-a (1.8 g, 47%) as a pale-yellow oily substance. cooling followed by extraction with ether The organic layer was washed with a 1N aqueous solution of sodium hydroxide and with a saturated saline dried over sodium sulfate The solvent was distilled off the residue was purified by column chromatography (hexane:ethyl acetate=10:1 and 5:1) to give Compound IIn-a (1.8 g, 47%) as a pale-yellow oily substance

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

Procedure: 2-Bromo-3-hydroxy-4-methoxybenzaldehyde (1.68 g) was dissolved in DMF (17 ml), and sodium hydride (0.209 g) was added thereto under ice-cooling, followed by stirring for 30 minutes. Allyl bromide (0.944 ml) was added to the mixture, followed by stirring at 60° C. for one hour. After being allowed to stand for cooling, water was added to the mixture and the precipitated solid was collected by filtration. The obtained crude crystals were recrystallized from isopropanol to give Compound IIe-a (1.30 g, 66%). under ice-cooling by stirring at 60° C. for one hour for cooling the precipitated solid was collected by filtration The obtained crude crystals were recrystallized from isopropanol to give Compound IIe-a (1.30 g, 66%)

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromo-3-hydroxy-4-methoxybenzaldehyde (225.2 g, 975 mmol) and DMF (660 ml) were mixed, and potassium carbonate (148.2 g, 1.07 mol) and bromopentane (133 ml, 1.07 mol) were successively added to this solution. The mixture was stirred at 90° C. for 1.5 hours and cooled to room temperature. Water (800 ml) was added to stop the reaction. The aqueous layer was extracted successively with diethyl ether (1000 ml, 500 ml) and ethyl acetate (500 ml). The organic layers were combined, washed successively with water (200 ml) and saturated brine (200 ml) and dried over anhydrous sodium sulfate. The drying agent was filtered off, and the filtrate was concentrated under reduced pressure to give a crude product of 2-bromo4-methoxy-3-pentyloxybenzaldehyde. cooled to room temperature the reaction The aqueous layer was extracted successively with diethyl ether (1000 ml, 500 ml) and ethyl acetate (500 ml) washed successively with water (200 ml) and saturated brine (200 ml) dried over anhydrous sodium sulfate The drying agent was filtered off the filtrate was concentrated under reduced pressure

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromo-3-hydroxy-4-methoxybenzaldehyde (225.2 g, 975 mmol) and DMF (660 ml) were mixed, and potassium carbonate (148.2 g, 1.07 mol) and bromopentane (133 ml, 1.07 mol) were successively added to this solution. The mixture was stirred at 90° C. for 1.5 hours and cooled to room temperature. Water (800 ml) was added to stop the reaction. The aqueous layer was extracted successively with diethyl ether (1000 ml, 500 ml) and ethyl acetate (500 ml). The organic layers were combined, washed successively with water (200 ml) and saturated brine (200 ml) and dried over anhydrous sodium sulfate. The drying agent was filtered off, and the filtrate was concentrated under reduced pressure to give a crude product of 2-bromo4-methoxy-3-pentyloxybenzaldehyde. cooled to room temperature the reaction The aqueous layer was extracted successively with diethyl ether (1000 ml, 500 ml) and ethyl acetate (500 ml) washed successively with water (200 ml) and saturated brine (200 ml) dried over anhydrous sodium sulfate The drying agent was filtered off the filtrate was concentrated under reduced pressure

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

Procedure: 3-Hydroxy-4-methoxybenzaldehyde (200 g, 1.31 mol), dioxane (1000 ml) and water (400 ml) were mixed, and N-bromosuccinimide (245.7 g, 1.38 mol) was added over 10 minutes. After 60 and 70 minutes, N-bromosuccinimide was further added in an amount of 16.4 g (92.1 mmol) and 7.02 g (39.4 mmol), respectively, and the mixture was further stirred for 30 minutes. Water (1600 ml) was added, and the precipitated crystals were collected by filtration. The crystals were washed with water (1000 ml) to give 2-bromo-3-hydroxy-4-methoxybenzaldehyde (227.1 g, 74.8%) as pale-red crystals. the precipitated crystals were collected by filtration The crystals were washed with water (1000 ml)

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred suspension of potassium fluoride (1.89 gm, 0.0326 mol) in dry DMSO (10 ml) was added a solution of 2-bromoisovanillin (5.0 gm, 0.0217 mol) in DMSO (10 ml). A solution of 4-fluoronitrobenzene (5.0 gm, 0.0260 mol) in DMSO (5 ml) was added to the above suspension and the reaction mixture was stirred at 140° C. for 4 h. The reaction mixture was cooled to room temperature and the contents were poured into water (150 ml) and extracted with ethyl acetate (50 ml×3). The organic extracts were combined and washed with 1N sodium hydroxide (25 ml×2), water and brine and dried over anhydrous sodium sulfate. The dried organic layer was concentrated in vacuo and the residue was purified by silica-gel column chromatography using 20% ethyl acetate-petroleum ether as the eluent to give 2-bromo-3-(p-nitrophenoxy)-4-methoxy benzaldehyde as a pale yellow solid (5.0 gm) mp:132-140° C. The reaction mixture was cooled to room temperature extracted with ethyl acetate (50 ml×3) washed with 1N sodium hydroxide (25 ml×2), water and brine dried over anhydrous sodium sulfate The dried organic layer was concentrated in vacuo the residue was purified by silica-gel column chromatography

Conditions: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred suspension of potassium fluoride (1.89 gm, 0.0326 mol) in dry DMSO (10 ml) was added a solution of 2-bromoisovanillin (5.0 gm, 0.0217 mol) in DMSO (10 ml). A solution of 4-fluoronitrobenzene (5.0 gm, 0.0260 mol) in DMSO (5 ml) was added to the above suspension and the reaction mixture was stirred at 140° C. for 4 h. The reaction mixture was cooled to room temperature and the contents were poured into water (150 ml) and extracted with ethyl acetate (50 ml×3). The organic extracts were combined and washed with 1N sodium hydroxide (25 ml×2), water and brine and dried over anhydrous sodium sulfate. The dried organic layer was concentrated in vacuo and the residue was purified by silica-gel column chromatography using 20% ethyl acetate-petroleum ether as the eluent to give 2-bromo-3-(p-nitrophenoxy)-4-methoxy benzaldehyde as a pale yellow solid (5.0 gm) mp:132-140° C. The reaction mixture was cooled to room temperature extracted with ethyl acetate (50 ml×3) washed with 1N sodium hydroxide (25 ml×2), water and brine dried over anhydrous sodium sulfate The dried organic layer was concentrated in vacuo the residue was purified by silica-gel column chromatography