3-oxobutyl benzoate

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

Procedure: Reaction was carried out under nitrogen atmosphere. To 400 ml of tetrahydrofuran, 46.2 g (0.22 mol) of dibromodifluoromethane was dissolved, followed by drop-wise adding 70.2 g (0.43 mol) of tris (dimethylamino)phosphine at −10° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature for 1 hour, and 150 ml tetrahydrofuran solution dissolving with 19.2 g (0.10 mol) of 3-oxobutylbenzoate was further added drop-wise at −20° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature overnight. To this mixture, diethyl ether was added, followed by washing with dilute hydrochloric acid, a saturated aqueous solution of sodium hydrogencarbonate and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate, and concentrating under reduced pressure. The residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8) to obtain 16.4 g (yield: 72%) of 4,4-difluoro-3-methyl-3-butenyl benzoate. Reaction After the end of the drop-wise addition the reaction liquid at −20° C After the end of the drop-wise addition the reaction liquid was stirred at room temperature overnight by washing with dilute hydrochloric acid by drying over anhydrous magnesium sulfate concentrating under reduced pressure The residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8)

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

Procedure: To 400 ml of tetrahydrofuran in a reactor, 15.0 g (0.17 mol) of 3-oxo-1-butanol and 26.3 g (0.19 mol) of benzoyl chloride were dissolved, followed by drop-wise adding 20.6 g (0.20 mol) of triethylamine under ice-cooling. After the end of drop-wise addition, the reaction liquid was stirred at room temperature for 3 hours. Hydrochloric acid salt of triethylamine was filtered, followed by adding water to the filtrate and extracting with ethyl acetate. The organic layer was washed with water, a saturated aqueous solution of sodium carbonate, water and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate and concentrating under reduced pressure. The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5 to 1:3) to obtain 31.5 g (yield: 96%) of 3-oxobutylbenzoate. cooling After the end of drop-wise addition the reaction liquid Hydrochloric acid salt of triethylamine was filtered by adding water to the filtrate extracting with ethyl acetate The organic layer was washed with water by drying over anhydrous magnesium sulfate concentrating under reduced pressure The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5 to 1:3)

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

Procedure: A process for the production of 2,3,6-trimethylphenol which comprises reacting a carbonyl compound selected from the group consisting of methyl vinyl ketone, methyl β-hydroxyethyl ketone, methyl β-methoxyethyl ketone, methyl β-phenoxyethyl ketone, methyl β-acetyloxyethyl ketone, methyl β-benzoyloxyethyl ketone, methyl β-methyl-sulfonyloxyethyl ketone, methyl β-phenylsulfonyloxyethyl ketone, methyl β-dimethylaminoethyl ketone, methyl β-chloroethyl ketone, dimethyl-(β-acetylethyl)-sulfonium bromide or trimethyl-(β-acetylethyl)-ammonium iodide to a mixture of diethyl ketone and a basic reagent selected from the group consisting of an alkali metal, an alkaline earth metal, a hydroxide, oxide, alcoholate, amide, hydride or organo metallic compound of an alkali metal or alkaline earth metal, and a quaternary ammonium hydroxide, the amount of said diethyl ketone being in the molar ratio of 1:1 to 50:1 with respect to the total amount of carbonyl compound added, at a reaction temperature of 20° to 150° C. to produce 2,3,6-trimethyl-2-cyclohexen-1-one, and dehydrogenating the latter to produce 2,3,6-trimethylphenol.

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

Procedure: A process for the production of 2,3,6-trimethylphenol which comprises reacting a carbonyl compound selected from the group consisting of methyl vinyl ketone, methyl β-hydroxyethyl ketone, methyl β-methoxyethyl ketone, methyl β-phenoxyethyl ketone, methyl β-acetyloxyethyl ketone, methyl β-benzoyloxyethyl ketone, methyl β-methyl-sulfonyloxyethyl ketone, methyl β-phenylsulfonyloxyethyl ketone, methyl β-dimethylaminoethyl ketone, methyl β-chloroethyl ketone, dimethyl-(β-acetylethyl)-sulfonium bromide or trimethyl-(β-acetylethyl)-ammonium iodide to a mixture of diethyl ketone and a basic reagent selected from the group consisting of an alkali metal, an alkaline earth metal, a hydroxide, oxide, alcoholate, amide, hydride or organo metallic compound of an alkali metal or alkaline earth metal, and a quaternary ammonium hydroxide, the amount of said diethyl ketone being in the molar ratio of 1:1 to 50:1 with respect to the total amount of carbonyl compound added, at a reaction temperature of 20° to 150° C. to produce 2,3,6-trimethyl-2-cyclohexen-1-one, and dehydrogenating the latter to produce 2,3,6-trimethylphenol.

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

Procedure: Reaction was carried out under nitrogen atmosphere. To 400 ml of tetrahydrofuran, 46.2 g (0.22 mol) of dibromodifluoromethane was dissolved, followed by drop-wise adding 70.2 g (0.43 mol) of tris (dimethylamino)phosphine at −10° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature for 1 hour, and 150 ml tetrahydrofuran solution dissolving with 19.2 g (0.10 mol) of 3-oxobutylbenzoate was further added drop-wise at −20° C. After the end of the drop-wise addition, the reaction liquid was stirred at room temperature overnight. To this mixture, diethyl ether was added, followed by washing with dilute hydrochloric acid, a saturated aqueous solution of sodium hydrogencarbonate and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate, and concentrating under reduced pressure. The residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8) to obtain 16.4 g (yield: 72%) of 4,4-difluoro-3-methyl-3-butenyl benzoate. Reaction After the end of the drop-wise addition the reaction liquid at −20° C After the end of the drop-wise addition the reaction liquid was stirred at room temperature overnight by washing with dilute hydrochloric acid by drying over anhydrous magnesium sulfate concentrating under reduced pressure The residue was purified by silica gel column chromatography (diisopropyl ether:hexane=1:8)

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

Procedure: To 400 ml of tetrahydrofuran in a reactor, 15.0 g (0.17 mol) of 3-oxo-1-butanol and 26.3 g (0.19 mol) of benzoyl chloride were dissolved, followed by drop-wise adding 20.6 g (0.20 mol) of triethylamine under ice-cooling. After the end of drop-wise addition, the reaction liquid was stirred at room temperature for 3 hours. Hydrochloric acid salt of triethylamine was filtered, followed by adding water to the filtrate and extracting with ethyl acetate. The organic layer was washed with water, a saturated aqueous solution of sodium carbonate, water and a saturated saline solution in this order, followed by drying over anhydrous magnesium sulfate and concentrating under reduced pressure. The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5 to 1:3) to obtain 31.5 g (yield: 96%) of 3-oxobutylbenzoate. cooling After the end of drop-wise addition the reaction liquid Hydrochloric acid salt of triethylamine was filtered by adding water to the filtrate extracting with ethyl acetate The organic layer was washed with water by drying over anhydrous magnesium sulfate concentrating under reduced pressure The residue was purified with silica gel column chromatography (ethyl acetate:hexane=1:5 to 1:3)

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

Procedure: A process for the production of 2,3,6-trimethylphenol which comprises reacting a carbonyl compound selected from the group consisting of methyl vinyl ketone, methyl β-hydroxyethyl ketone, methyl β-methoxyethyl ketone, methyl β-phenoxyethyl ketone, methyl β-acetyloxyethyl ketone, methyl β-benzoyloxyethyl ketone, methyl β-methyl-sulfonyloxyethyl ketone, methyl β-phenylsulfonyloxyethyl ketone, methyl β-dimethylaminoethyl ketone, methyl β-chloroethyl ketone, dimethyl-(β-acetylethyl)-sulfonium bromide or trimethyl-(β-acetylethyl)-ammonium iodide to a mixture of diethyl ketone and a basic reagent selected from the group consisting of an alkali metal, an alkaline earth metal, a hydroxide, oxide, alcoholate, amide, hydride or organo metallic compound of an alkali metal or alkaline earth metal, and a quaternary ammonium hydroxide, the amount of said diethyl ketone being in the molar ratio of 1:1 to 50:1 with respect to the total amount of carbonyl compound added, at a reaction temperature of 20° to 150° C. to produce 2,3,6-trimethyl-2-cyclohexen-1-one, and dehydrogenating the latter to produce 2,3,6-trimethylphenol.