4-乙酰基-2-丁酮

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 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.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 130 g of 1-acetoxybutan-3-one and sodium methylate solution in methanol are dripped in the course of one hour from separate supply vessels while stirring into 400 g of boiling diethyl ketone at such a rate that the reaction mixture remains constantly alkaline. A total of 190 g of a 30% by weight sodium methylate solution is used up in this way. The whole is then heated under reflux for another hour and then neutralized with glacial acetic acid. Deposited sodium acetate is filtered off and the filtrate is subjected to fractional distillation. 81 g of 2,3,6-trimethyl-2-cyclohexen-1-one is obtained as well as traces of 4-methyl-3-ethyl-2-cyclohexen-1-one. The yield with reference to 1-acetoxybutan-3-one is 59%. are dripped in the course of one hour from separate supply vessels The whole is then heated under reflux for another hour Deposited sodium acetate is filtered off the filtrate is subjected to fractional distillation

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 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.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 130 g of 1-acetoxybutan-3-one and sodium methylate solution in methanol are dripped in the course of one hour from separate supply vessels while stirring into 400 g of boiling diethyl ketone at such a rate that the reaction mixture remains constantly alkaline. A total of 190 g of a 30% by weight sodium methylate solution is used up in this way. The whole is then heated under reflux for another hour and then neutralized with glacial acetic acid. Deposited sodium acetate is filtered off and the filtrate is subjected to fractional distillation. 81 g of 2,3,6-trimethyl-2-cyclohexen-1-one is obtained as well as traces of 4-methyl-3-ethyl-2-cyclohexen-1-one. The yield with reference to 1-acetoxybutan-3-one is 59%. are dripped in the course of one hour from separate supply vessels The whole is then heated under reflux for another hour Deposited sodium acetate is filtered off the filtrate is subjected to fractional distillation

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Crude 4-acetoxy-2-butanone was prepared as follows. A mixture of 4-hydroxy-2-butanone (101.48 g) and acetic anhydride (131.05 g) was stirred and heated to about 120° C. for about 40 minutes before the acetic acid by-product was removed by vacuum distillation at about 24 torr and vapor temperatures rising to about 49° C. The distillation residue was about 129.0 g of crude 4-acetoxy-2-butanone. was removed by vacuum distillation at about 24 torr and vapor temperatures rising to about 49° C

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: The method described in Example 5 is followed starting with glycerol and 4-hydroxy-2-butanone, suitably protected at the hydroxy group with an acetyl radical. 4-acetoxy-2-butanone is prepared starting from ethyl acetoacetate, protected at the carbonyl group as diethylacetal, by reduction with lithium-aluminium hydride, followed by restoring the keto group by means of silica in the presence of water (A: Banerje 8 G. P. Kalena, Synth. Commun (1982) 12, 225). 1,3-dioxolane-2-methyl-2'-(2-hydroxyethyl-4-acetylthiomethylene distills at 164°-170° C. (10 mm Hg). Yield 61%. 1,3-dioxolane-2-methyl-2'-(2-hydroxyethyl-4-acetylthiomethylene distills at 164°-170° C. (10 mm Hg)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 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.

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 130 g of 1-acetoxybutan-3-one and sodium methylate solution in methanol are dripped in the course of one hour from separate supply vessels while stirring into 400 g of boiling diethyl ketone at such a rate that the reaction mixture remains constantly alkaline. A total of 190 g of a 30% by weight sodium methylate solution is used up in this way. The whole is then heated under reflux for another hour and then neutralized with glacial acetic acid. Deposited sodium acetate is filtered off and the filtrate is subjected to fractional distillation. 81 g of 2,3,6-trimethyl-2-cyclohexen-1-one is obtained as well as traces of 4-methyl-3-ethyl-2-cyclohexen-1-one. The yield with reference to 1-acetoxybutan-3-one is 59%. are dripped in the course of one hour from separate supply vessels The whole is then heated under reflux for another hour Deposited sodium acetate is filtered off the filtrate is subjected to fractional distillation