1-(2,3-dichlorophenyl)ethanone

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: A mixture of 2′,3′-dichloroacetophenone (50 mmol), ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL) ammonium acetate (400 mg), and benzene (50 mL) is heated to reflux in a Dean-Stark apparatus. After approximately 10 hours, additional ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), and ammonium acetate (400 mg) are added. After an additional 10 hours, the reaction is cooled to room temperature, diluted with ethyl acetate (30 mL), washed with water (240 mL), brine (40 mL), and dried (Na2SO4). After filtering, the extract is concentrated in vacuo and the desired product, as a mixture of E and Z-isomers, is isolated by column chromatography on silica gel, eluting with 5% ethyl acetate in petroleum ether. is heated to reflux in a Dean-Stark apparatus After an additional 10 hours washed with water (240 mL), brine (40 mL) dried (Na2SO4) After filtering the extract is concentrated in vacuo the desired product, as a mixture of E and Z-isomers is isolated by column chromatography on silica gel eluting with 5% ethyl acetate in petroleum ether

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

Procedure: A mixture of 2′,3′-dichloroacetophenone (50 mmol), ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL) ammonium acetate (400 mg), and benzene (50 mL) is heated to reflux in a Dean-Stark apparatus. After approximately 10 hours, additional ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), and ammonium acetate (400 mg) are added. After an additional 10 hours, the reaction is cooled to room temperature, diluted with ethyl acetate (30 mL), washed with water (240 mL), brine (40 mL), and dried (Na2SO4). After filtering, the extract is concentrated in vacuo and the desired product, as a mixture of E and Z-isomers, is isolated by column chromatography on silica gel, eluting with 5% ethyl acetate in petroleum ether. is heated to reflux in a Dean-Stark apparatus After an additional 10 hours washed with water (240 mL), brine (40 mL) dried (Na2SO4) After filtering the extract is concentrated in vacuo the desired product, as a mixture of E and Z-isomers is isolated by column chromatography on silica gel eluting with 5% ethyl acetate in petroleum ether

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

Procedure: To a stirred solution of 120 parts of 1-(2,3-dichlorophenyl)-1-ethanone in 240 parts of butanol are added dropwise 101 parts of bromine at room temperature. After stirring for 1 hour at room temperature, there are added successively 42 parts of 1,2-ethanediol, 540 parts of anhydrous benzene and 4 parts of 4-methylbenzenesulfonic acid. The whole is stirred and refluxed overnight with water-separator. The reaction mixture is evaporated and the residue is dissolved in 2,2'-oxybispropane. The solution is washed with a diluted sodium hydroxide solution and three times with water, dried, filtered and evaporated. The residue is distilled, yielding 96.6 parts (49%) of 2-(bromomethyl)-2-(2,3-dichlorophenyl)-1,3-dioxolane; bp. 135°-137° C. at 0.1 mm. pressure. The whole is stirred The reaction mixture is evaporated the residue is dissolved in 2,2'-oxybispropane The solution is washed with a diluted sodium hydroxide solution and three times with water dried filtered evaporated The residue is distilled

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

Procedure: To a stirred solution of 120 parts of 1-(2,3-dichlorophenyl)-1-ethanone in 240 parts of butanol are added dropwise 101 parts of bromine at room temperature. After stirring for 1 hour at room temperature, there are added successively 42 parts of 1,2-ethanediol, 540 parts of anhydrous benzene and 4 parts of 4-methylbenzenesulfonic acid. The whole is stirred and refluxed overnight with water-separator. The reaction mixture is evaporated and the residue is dissolved in 2,2'-oxybispropane. The solution is washed with a diluted sodium hydroxide solution and three times with water, dried, filtered and evaporated. The residue is distilled, yielding 96.6 parts (49%) of 2-(bromomethyl)-2-(2,3-dichlorophenyl)-1,3-dioxolane; bp. 135°-137° C. at 0.1 mm. pressure. The whole is stirred The reaction mixture is evaporated the residue is dissolved in 2,2'-oxybispropane The solution is washed with a diluted sodium hydroxide solution and three times with water dried filtered evaporated The residue is distilled

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: α-Methyl-2,3-dichlorobenzyl alcohol (5.0 g, 0.026 mol) was dissolved in acetic acid (24 ml) and 12% w/v sodium hypochlorite solution (23.26 ml, 0.0314 mol) was added slowly dropwise, with stirring, at a temperature of 15-25° C. When the addition was complete the reaction mixture was stirred at ambient temperature for approximately 1% hours until a starch/iodide test gave a positive result. Saturated sodium bisulphite solution was added to the reaction mixture until the starch/iodide test was negative. The mixture was poured onto ice/brine (100 ml) and extracted with diethyl ether (3×75 ml). The ether phases were combined and washed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes were alkaline. The ether phase was dried over anhydrous magnesium sulphate, filtered and evaporated down. 2,3-Dichloroacetophenone (3.2 g, 65% yield) was afforded as a pale-yellow oil. T.l.c. (SiO2 ;CHCl3) and nmr showed this material to contain no impurities. was added slowly dropwise When the addition gave a positive result The mixture was poured onto ice/brine (100 ml) extracted with diethyl ether (3×75 ml) washed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes The ether phase was dried over anhydrous magnesium sulphate filtered evaporated down

Conditions: temp:20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: α-Methyl-2,3-dichlorobenzyl alcohol (5.0 g, 0.026 mol) was dissolved in acetic acid (24 ml) and 12% w/v sodium hypochlorite solution (23.26 ml, 0.0314 mol) was added slowly dropwise, with stirring, at a temperature of 15-25° C. When the addition was complete the reaction mixture was stirred at ambient temperature for approximately 1% hours until a starch/iodide test gave a positive result. Saturated sodium bisulphite solution was added to the reaction mixture until the starch/iodide test was negative. The mixture was poured onto ice/brine (100 ml) and extracted with diethyl ether (3×75 ml). The ether phases were combined and washed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes were alkaline. The ether phase was dried over anhydrous magnesium sulphate, filtered and evaporated down. 2,3-Dichloroacetophenone (3.2 g, 65% yield) was afforded as a pale-yellow oil. T.l.c. (SiO2 ;CHCl3) and nmr showed this material to contain no impurities. was added slowly dropwise When the addition gave a positive result The mixture was poured onto ice/brine (100 ml) extracted with diethyl ether (3×75 ml) washed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes The ether phase was dried over anhydrous magnesium sulphate filtered evaporated down

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

Procedure: A mixture of 2′,3′-dichloroacetophenone (50 mmol), ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL) ammonium acetate (400 mg), and benzene (50 mL) is heated to reflux in a Dean-Stark apparatus. After approximately 10 hours, additional ethyl cyanoacetate (50 mmol), acetic acid (1.14 mL), and ammonium acetate (400 mg) are added. After an additional 10 hours, the reaction is cooled to room temperature, diluted with ethyl acetate (30 mL), washed with water (240 mL), brine (40 mL), and dried (Na2SO4). After filtering, the extract is concentrated in vacuo and the desired product, as a mixture of E and Z-isomers, is isolated by column chromatography on silica gel, eluting with 5% ethyl acetate in petroleum ether. is heated to reflux in a Dean-Stark apparatus After an additional 10 hours washed with water (240 mL), brine (40 mL) dried (Na2SO4) After filtering the extract is concentrated in vacuo the desired product, as a mixture of E and Z-isomers is isolated by column chromatography on silica gel eluting with 5% ethyl acetate in petroleum ether

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

Procedure: To a stirred solution of 120 parts of 1-(2,3-dichlorophenyl)-1-ethanone in 240 parts of butanol are added dropwise 101 parts of bromine at room temperature. After stirring for 1 hour at room temperature, there are added successively 42 parts of 1,2-ethanediol, 540 parts of anhydrous benzene and 4 parts of 4-methylbenzenesulfonic acid. The whole is stirred and refluxed overnight with water-separator. The reaction mixture is evaporated and the residue is dissolved in 2,2'-oxybispropane. The solution is washed with a diluted sodium hydroxide solution and three times with water, dried, filtered and evaporated. The residue is distilled, yielding 96.6 parts (49%) of 2-(bromomethyl)-2-(2,3-dichlorophenyl)-1,3-dioxolane; bp. 135°-137° C. at 0.1 mm. pressure. The whole is stirred The reaction mixture is evaporated the residue is dissolved in 2,2'-oxybispropane The solution is washed with a diluted sodium hydroxide solution and three times with water dried filtered evaporated The residue is distilled

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: To 14 g of sodium hydride (50%) were added dropwise 21.3 g of diethyl oxalate, 0.54 ml of ethanol and then 160 ml of ether solution containing 30 g of 2,3-dichloroacetophenone with stirring under cooling with ice. The reaction was carried out under the state free from water. The reaction was continued at room temperature for 40 minutes with stirring after the dropping and further carried out for 45 minutes under reflux. The reaction mixture was poured into ice-cold water containing 17.5 g of acetic acid and after stirring the mixture was filtered. The organic layer was separated, dehydrated and concentrated. The residue was recrystallized from n-hexane to obtain 14.5 g of ethyl 4-(2,3-dichlorophenyl)-2,4-dioxobutyrate (white needles, m.p. 57°-58° C.). under cooling with ice with stirring after the dropping further carried out for 45 minutes under reflux after stirring the mixture was filtered The organic layer was separated concentrated The residue was recrystallized from n-hexane

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

Procedure: To 14 g of sodium hydride (50%) were added dropwise 21.3 g of diethyl oxalate, 0.54 ml of ethanol and then 160 ml of ether solution containing 30 g of 2,3-dichloroacetophenone with stirring under cooling with ice. The reaction was carried out under the state free from water. The reaction was continued at room temperature for 40 minutes with stirring after the dropping and further carried out for 45 minutes under reflux. The reaction mixture was poured into ice-cold water containing 17.5 g of acetic acid and after stirring the mixture was filtered. The organic layer was separated, dehydrated and concentrated. The residue was recrystallized from n-hexane to obtain 14.5 g of ethyl 4-(2,3-dichlorophenyl)-2,4-dioxobutyrate (white needles, m.p. 57°-58° C.). under cooling with ice with stirring after the dropping further carried out for 45 minutes under reflux after stirring the mixture was filtered The organic layer was separated concentrated The residue was recrystallized from n-hexane