1,4-Dibromo-2-(bromomethyl)benzene

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: In a three-necked round-bottom 1000 ml flask equipped with a reflux condenser, dropping funnel with pressure-equalizing, and magnetic stirring bar 6.10 g (0.27 mol) of sodium metal were dissolved in 150 ml of dry ethanol. To the resulting solution 45.5 g (0.26 mol) of diethylmethylmalonate in 50 ml of dry ethanol were added dropwise within 10 min. This mixture was stirred for 15 min; then 84.3 g (0.26 mol) of 3,6-dibromobenzylbromide were added by vigorous stirring at a rate that allowed the reaction mixture to maintain a gentle reflux. Additionally, this mixture was refluxed for 4 h and, then, cooled to room temperature. A solution of 52.1 g of KOH in 140 ml of water was added. This mixture was refluxed for 3 h to saponificate the ester formed. Ethanol and water were distilled off. To the residue 200 ml of water and, then, 12 M HCl (to pH 1) were added. The substituted methylmalonic acid precipitated was separated, washed with 3×100 ml of cold water and dried overnight on a watch glass. Crude 3-(2,5-dibromophenyl)-2-methylpropanoic acid was obtained after decarboxylation of this substituted methylmalonic acid by heating it for 2 h at 160° C. This product was used without further purification. A mixture of this acid, 70 ml of SOCl2, and 100 ml of CH2Cl2 was stirred for 3 h at reflux. Thionyl chloride and CH2Cl2 were distilled off. The residue was dried in vacuum and, then, dissolved in 95 ml of CH2Cl2. To a suspension of 47.0 g (0.35 mol) of AlCl3 in 470 ml of CH2Cl2 the above-obtained solution of 3-(2,5-dibromophenyl)-2-methylpropanoyl chloride was added dropwise by vigorous stirring for 1 h at −20° C. This mixture was refluxed for 3 h, cooled to ambient temperature, and, then, poured on 500 cm3 of ice. The organic layer was separated. The aqueous layer was extracted with 3×200 ml of methyl-tert-butyl ether. The combined organic fractions were dried over K2CO3 and evaporated to dryness. The crude 4,7-dibromo-2-methyl-1-indanone was purified by flash chromatography on Silica Gel 60 (40-63 μm, d 50 mm, h 250 mm; eluent:hexanes/methyl-tert-butyl ether (1:1, vol.)). Yield 54.1 g (70%). In a three-necked round-bottom 1000 ml flask equipped with a reflux condenser by vigorous stirring at a rate that to maintain a gentle reflux Additionally, this mixture was refluxed for 4 h This mixture was refluxed for 3 h formed Ethanol and water were distilled off To the residue 200 ml of water and, then, 12 M HCl (to pH 1) were added The substituted methylmalonic acid precipitated was separated washed with 3×100 ml of cold water dried overnight on a watch glass

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: In a three-necked round-bottom 1000 ml flask equipped with a reflux condenser, dropping funnel with pressure-equalizing, and magnetic stirring bar 6.10 g (0.27 mol) of sodium metal were dissolved in 150 ml of dry ethanol. To the resulting solution 45.5 g (0.26 mol) of diethylmethylmalonate in 50 ml of dry ethanol were added dropwise within 10 min. This mixture was stirred for 15 min; then 84.3 g (0.26 mol) of 3,6-dibromobenzylbromide were added by vigorous stirring at a rate that allowed the reaction mixture to maintain a gentle reflux. Additionally, this mixture was refluxed for 4 h and, then, cooled to room temperature. A solution of 52.1 g of KOH in 140 ml of water was added. This mixture was refluxed for 3 h to saponificate the ester formed. Ethanol and water were distilled off. To the residue 200 ml of water and, then, 12 M HCl (to pH 1) were added. The substituted methylmalonic acid precipitated was separated, washed with 3×100 ml of cold water and dried overnight on a watch glass. Crude 3-(2,5-dibromophenyl)-2-methylpropanoic acid was obtained after decarboxylation of this substituted methylmalonic acid by heating it for 2 h at 160° C. This product was used without further purification. A mixture of this acid, 70 ml of SOCl2, and 100 ml of CH2Cl2 was stirred for 3 h at reflux. Thionyl chloride and CH2Cl2 were distilled off. The residue was dried in vacuum and, then, dissolved in 95 ml of CH2Cl2. To a suspension of 47.0 g (0.35 mol) of AlCl3 in 470 ml of CH2Cl2 the above-obtained solution of 3-(2,5-dibromophenyl)-2-methylpropanoyl chloride was added dropwise by vigorous stirring for 1 h at −20° C. This mixture was refluxed for 3 h, cooled to ambient temperature, and, then, poured on 500 cm3 of ice. The organic layer was separated. The aqueous layer was extracted with 3×200 ml of methyl-tert-butyl ether. The combined organic fractions were dried over K2CO3 and evaporated to dryness. The crude 4,7-dibromo-2-methyl-1-indanone was purified by flash chromatography on Silica Gel 60 (40-63 μm, d 50 mm, h 250 mm; eluent:hexanes/methyl-tert-butyl ether (1:1, vol.)). Yield 54.1 g (70%). In a three-necked round-bottom 1000 ml flask equipped with a reflux condenser by vigorous stirring at a rate that to maintain a gentle reflux Additionally, this mixture was refluxed for 4 h This mixture was refluxed for 3 h formed Ethanol and water were distilled off To the residue 200 ml of water and, then, 12 M HCl (to pH 1) were added The substituted methylmalonic acid precipitated was separated washed with 3×100 ml of cold water dried overnight on a watch glass

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: In a three-necked round-bottom 250 ml flask equipped with a reflux condenser, thermometer, dropping funnel with pressure-equalizing, and magnetic stirring bar 15.5 ml (47.9 g, 0.30 mmol) of bromine were added dropwise to 74.9 g (0.30 mol) of 3,6-dibromotoluene under exposure to 500 W lamp for 3 h at 190° C. The resulting mixture was cooled to room temperature. Fractional distillation gave a colorless liquid, b.p. 132-135° C./3 mm Hg. Yield 84.3 g (85%). In a three-necked round-bottom 250 ml flask equipped with a reflux condenser Fractional distillation gave a colorless liquid, b.p. 132-135° C./3 mm Hg

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: In a three-necked round-bottom 250 ml flask equipped with a reflux condenser, thermometer, dropping funnel with pressure-equalizing, and magnetic stirring bar 15.5 ml (47.9 g, 0.30 mmol) of bromine were added dropwise to 74.9 g (0.30 mol) of 3,6-dibromotoluene under exposure to 500 W lamp for 3 h at 190° C. The resulting mixture was cooled to room temperature. Fractional distillation gave a colorless liquid, b.p. 132-135° C./3 mm Hg. Yield 84.3 g (85%). In a three-necked round-bottom 250 ml flask equipped with a reflux condenser Fractional distillation gave a colorless liquid, b.p. 132-135° C./3 mm Hg

反応条件: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 33 g (0.1 mole) 2,5-dibromo toluene is placed in a 100 ml three-necked flask, fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem reaching nearly to the bottom of the flask. The flask is illuminated with two 300-watt tungsten lamps during the reaction. The flask is heated in an oil bath to 150° C., and 18.4 g (5.9 ml, 0.115 mole) bromine is added over two hours. The mixture is stirred for an additional 10 minutes, and the contents, while still liquid, are poured into a 500 ml round-bottom flask containing 300 ml of hot light petroleum ether and 2 g decolorizing carbon. A reflux condenser is attached, and the mixture is heated to reflux until the material dissolves, then rapidly filtered through a pre-heated Buchner funnel. The filtrate is cooled and washed with cold light petroleum. fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem the contents, while still liquid, are poured into a 500 ml round-bottom flask A reflux condenser is attached the mixture is heated to reflux until the material dissolves rapidly filtered through a pre-heated Buchner funnel The filtrate is cooled washed with cold light petroleum

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: A mixture of 25.03 g (0.165 mol) of 2-(1,3-dioxolan-2-yl)pyridine and 2,5-dibromobenzyl bromide (54 g, 0.165 mol) in 60 mL of sulfolane was heated on a steam-bath for 6 h. The mixture was diluted with 600 mL of ethyl acetate, cooled, and the resulting solid product was isolated by filtration. The above solid was triturated in 300 mL of ethyl acetate, the mixture was cooled, filtered and dried to afford 62.24 g (79%) of 1-(2,5-dibromobenzyl)-2-(1,3-dioxolan-2-yl)pyridinium bromide (Formula VI: R1 =R2 =H; R7 =2,5-Br2 ; Z- =Br-), as a yellow solid, m.p. 135°-139° C. was heated on a steam-bath for 6 h cooled the resulting solid product was isolated by filtration The above solid was triturated in 300 mL of ethyl acetate the mixture was cooled filtered dried

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of 75 g (0.3 mol) of 2,5-dibromotoluene in 1 L of carbon tetrachloride was added 58.73 g (0.33 mol) of NBS and 50 mg of benzyl peroxide, and the resulting mixture was refluxed with stirring for 24 h. The mixture was cooled, and concentrated in vacuo. The residue was crystallized from hot methanol and washed with hexane to afford 54.5 g (55.7%) of 2.5-dibromobenzyl bromide as a solid. the resulting mixture was refluxed The mixture was cooled concentrated in vacuo The residue was crystallized from hot methanol washed with hexane

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of 75 g (0.3 mol) of 2,5-dibromotoluene in 1 L of carbon tetrachloride was added 58.73 g (0.33 mol) of NBS and 50 mg of benzyl peroxide, and the resulting mixture was refluxed with stirring for 24 h. The mixture was cooled, and concentrated in vacuo. The residue was crystallized from hot methanol and washed with hexane to afford 54.5 g (55.7%) of 2.5-dibromobenzyl bromide as a solid. the resulting mixture was refluxed The mixture was cooled concentrated in vacuo The residue was crystallized from hot methanol washed with hexane

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 33 g (0.1 mole) 2,5-dibromo toluene is placed in a 100 ml three-necked flask, fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem reaching nearly to the bottom of the flask. The flask is illuminated with two 300-watt tungsten lamps during the reaction. The flask is heated in an oil bath to 150.C, and 18.4 g (5.9 ml, 0.115 mole) bromine is added over two hours. The mixture is stirred for an additional 10 minutes, and the contents, while still liquid, are poured into a 500 ml round-bottom flask containing 300 ml of hot light petroleum ether and 2 g decolorizing carbon. A reflux condenser is attached, and the mixture is heated to reflux until the material dissolves, then rapidly filtered through a pre-heated Buchner funnel. The filtrate is cooled and washed with cold light petroleum. fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem is added over two hours the contents, while still liquid, are poured into a 500 ml round-bottom flask A reflux condenser is attached the mixture is heated to reflux until the material dissolves rapidly filtered through a pre-heated Buchner funnel The filtrate is cooled washed with cold light petroleum

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: 33 g (0.1 mole) 2,5-dibromo toluene is placed in a 100 ml three-necked flask, fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem reaching nearly to the bottom of the flask. The flask is illuminated with two 300-watt tungsten lamps during the reaction. The flask is heated in an oil bath to 150.C, and 18.4 g (5.9 ml, 0.115 mole) bromine is added over two hours. The mixture is stirred for an additional 10 minutes, and the contents, while still liquid, are poured into a 500 ml round-bottom flask containing 300 ml of hot light petroleum ether and 2 g decolorizing carbon. A reflux condenser is attached, and the mixture is heated to reflux until the material dissolves, then rapidly filtered through a pre-heated Buchner funnel. The filtrate is cooled and washed with cold light petroleum. fitted with a reflux condenser, a sealed mechanical stirrer, and a separatory funnel with the stem is added over two hours the contents, while still liquid, are poured into a 500 ml round-bottom flask A reflux condenser is attached the mixture is heated to reflux until the material dissolves rapidly filtered through a pre-heated Buchner funnel The filtrate is cooled washed with cold light petroleum