2-methoxy-1-(2,4,6-trihydroxyphenyl)ethanone

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

Procedure: Under nitrogen atmosphere, 2-methoxy-1-(2,4,6-trihydroxyphenyl)ethanone (60 mg, 303.03 mmol), anhydrous potassium carbonate powder (250.9 g, 1.82 mmol), TBAB (tetrabutyl ammonium bromide, 145.9 mg, 454.52 mmol) and 4-fluorobenzoyl chloride (95.8 mg, 606 mmol) were dissolved in toluene (1200 mL), and refluxed for 6 hours. After cooling, toluene was removed, and then water (500 mL) was added. The aqueous solution was extracted with dichloromethane. The combined organic phase was washed with water and saturated brine, and dried over anhydrous sodium sulfate. A brown residue was obtained after removal of solvent. The residue was dissolved in a 5% potassium carbonate aqueous solution and heated to reflux for 2 hr. After cooling to ambient temperature, the mixture was acidified to pH 6 with 1N HCl solution, and extracted with dichloromethane three times. The combined organic phase was dried over anhydrous sodium sulfate, and the solvent was removed. The crude product was purified by silica gel column chromatography (eluent:ethyl acetate/petroleum ether, 1:5) and recrystallized in ethanol to give the desired compound (75 g, yield 81.9%). refluxed for 6 hours After cooling toluene was removed water (500 mL) was added The aqueous solution was extracted with dichloromethane The combined organic phase was washed with water and saturated brine dried over anhydrous sodium sulfate A brown residue was obtained after removal of solvent The residue was dissolved in a 5% potassium carbonate aqueous solution heated to reflux for 2 hr extracted with dichloromethane three times The combined organic phase was dried over anhydrous sodium sulfate the solvent was removed The crude product was purified by silica gel column chromatography (eluent:ethyl acetate/petroleum ether, 1:5) recrystallized in ethanol

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

Procedure: 2-methoxy-1-(2,4,6-trihydroxyphenyl)ethanone (8.3 g, 42 mmol) was dissolved in a 5% potassium hydroxide aqueous solution (84 ml). After the reaction mixture was cooled below 0° C., Isopentenyl bromide (12.48 g, 84 mmol) was slowly added dropwise to within 30 minutes. The reaction mixture was stirred at room temperature (RT) for 2 hours, then poured into an ice water and acidified to pH 2. The reaction mixture was extracted with ethyl acetate. The extract was collected and dried over anhydrous sodium sulfate, followed by removing solvent. The desired compound was obtained by purifying the residue by silica gel column chromatography (dichloromethane as eluent) (5.7 g, yield 41%). 1H NMR (400 MHz, DMSO-d6): δ=11.44 (s, 2H), 9.24 (s, 1H), 5.00 (t, 2H, J=6.8 Hz), 4.63 (s, 2H,), 3.31 (s, 3H), 3.22 (d, 4H, J=6.8 Hz), 1.67 (s, 6H), 1.58 (s, 6H). After the reaction mixture was cooled below 0° C. The reaction mixture was extracted with ethyl acetate The extract was collected dried over anhydrous sodium sulfate by removing solvent

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

Procedure: Phloroglucinol (35.1 g, 279 mmol) was dissolved into ethyl ether (500 mL) solution, followed by zinc chloride (8 g, 59 mmol) and 2-methoxy acetonitrile (18 g, 253 mmol) added in the solution under ice water bath condition. Dry HCl gas was bubbled into the reaction mixture, vigorously stirring for 5 hours, and precipitate was formed. The precipitate was filtered and collected, followed by dissolved into water and refluxed for 3 hours. After cooling, pink precipitate was collected, and desired white compound can be obtained after recrystallization with water. (45 g, yield 81%) 1HNMR (400 MHz, DMSO-d6): δ=12.14 (s, 2H), 10.41 (s, 1H), 5.79 (s, 2H), 4.56 (s, 2H), 3.32 (s, 3H). added in the solution under ice water bath condition Dry HCl gas was bubbled into the reaction mixture precipitate was formed The precipitate was filtered collected by dissolved into water refluxed for 3 hours After cooling pink precipitate was collected desired white compound can be obtained after recrystallization with water