2,4-dichloro-1-methylbenzene

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

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

Procedure: 500 parts of 2,4-dichlorotoluene (b.p.=198° to 200° C.) and 10 parts of anhydrous aluminum chloride were charged into a 1-liter four-necked flask provided with a reflux condenser, a thermometer, a stirrer and a dropping funnel. 397 parts of bromine was added dropwisely at 30° to 40° C. over a period of 5 hours. The reaction liquid was washed with warm water followed by separating the water layer, and then the oil layer was cooled. The separated crystals were filtered off, recrystallized from methanol to obtain 295 parts of 2,4-dichloro-5-bromotoluene having a melting point of 82.5° to 84.0° C. provided with a reflux condenser The reaction liquid was washed with warm water by separating the water layer the oil layer was cooled The separated crystals were filtered off recrystallized from methanol

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

Procedure: To stirred fuming nitric acid (200 ml) at 0° C. was added slowly 2,4-dichlorotoluene (50 g, 0.3mole). Upon completion of addition, the reaction mixture was stirred for one hour, then was poured into water (100 ml). A yellow precipitate was collected by filtration to yield 62.0 g of 2,4-dichloro-5-nitrotoluene, m.p. 40°-44° C. Upon completion of addition A yellow precipitate was collected by filtration

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 500 mL round bottom flask fitted with a Teflon magnetic stirrer was added 2,4-dichlorotoluene (Aldrich) (14.4 g, 90 mmol) in 300 mL glacial acetic acid. To this was added sodium bromide (9.4 g, 92 mmol) and anhydrous ceric ammonium nitrate (100 g, 182 mmol) and the reaction mixture was heated at 80° C. for 2.5 h. The reaction mixture was then poured into 1000 g of ice and water. The slurry was extracted with ether (3×200 mL) and the combined ether layers were washed with saturated aqueous sodium bicarbonate. The organic layer was dried over MgSO4, filtered, and the solvent removed under reduced pressure. The crude product was chromatographed by flash column chromatography on silica gel (eluted with 100% hexanes) and the desired product obtained. 1H-NMR 500 MHz (CDCl3): δ 4.58 (s, 2H), 7.28 (m, 1H), 7.43 (m, 2H), To a 500 mL round bottom flask fitted with a Teflon magnetic stirrer The slurry was extracted with ether (3×200 mL) the combined ether layers were washed with saturated aqueous sodium bicarbonate The organic layer was dried over MgSO4 filtered the solvent removed under reduced pressure The crude product was chromatographed by flash column chromatography on silica gel (eluted with 100% hexanes)

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 500 mL round bottom flask fitted with a Teflon magnetic stirrer was added 2,4-dichlorotoluene (Aldrich) (14.4 g, 90 mmol) in 300 mL glacial acetic acid. To this was added sodium bromide (9.4 g, 92 mmol) and anhydrous ceric ammonium nitrate (100 g, 182 mmol) and the reaction mixture was heated at 80° C. for 2.5 h. The reaction mixture was then poured into 1000 g of ice and water. The slurry was extracted with ether (3×200 mL) and the combined ether layers were washed with saturated aqueous sodium bicarbonate. The organic layer was dried over MgSO4, filtered, and the solvent removed under reduced pressure. The crude product was chromatographed by flash column chromatography on silica gel (eluted with 100% hexanes) and the desired product obtained. 1H-NMR 500 MHz (CDCl3): δ 4.58 (s, 2H), 7.28 (m, 1H), 7.43 (m, 2H), To a 500 mL round bottom flask fitted with a Teflon magnetic stirrer The slurry was extracted with ether (3×200 mL) the combined ether layers were washed with saturated aqueous sodium bicarbonate The organic layer was dried over MgSO4 filtered the solvent removed under reduced pressure The crude product was chromatographed by flash column chromatography on silica gel (eluted with 100% hexanes)

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

Procedure: To a mixture of 32 g of 4,6-dichlorotoluene and 0.3 g of anhydrous FeCl3, add, with stirring, 10 g of bromine in 1 g portions while maintaining a temperature of 20°-25° C. Add thereto a solution of 22 g of bromine in 100 mL of CCl4 slowly while maintaining a temperature of 20°-25° C. After the addition of bromine is complete, stir the mixture so formed for 15 min, and dilute the reaction mixture with 200 mL of CH2Cl2, and wash the organic solution with 5% aqueous sodium thiosulfate. Dry the organic layer over anhydrous K2CO3, filter, and evaporate to a residue. Recrystallize the residue from CH3CN to give 32 g of 2-bromo-4,6-dichlorotoluene, mp 84°-5° C. add Add stir the mixture so formed for 15 min wash the organic solution with 5% aqueous sodium thiosulfate Dry the organic layer over anhydrous K2CO3 filter evaporate to a residue Recrystallize the residue from CH3CN

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

Procedure: This example shows the utility of sulfided noble metals as a dehalogenation catalyst for substituted chlorobenzenes. The catalyst used was 0.5% palladium on 1/8" alumina. 2,4-Dichlorotoluene was used as the feed and the feed rate was maintained at about 1.25 g/min. The dehalogenation reaction catalysed by non-sulfided palladium at a temperature of 300° C. was found to be very vigorous. Up to 81% toluene was formed during such dehalogenation, yielding a mole ratio of toluene-chlorotoluene of 4.24. When the dehalogenation was catalysed by a sulfided palladium, the reaction rate was reduced considerably and the selectivity to chlorotoluene was improved. Only 41% toluene was found in the dehalogenated product which corresponded to a toluene/chlorotoluene mole ratio of 1.19. Thus sulfided palladium was found to be effective in improving selectivity to substituted chlorobenzene. the feed rate was maintained at about 1.25 g/min

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

Procedure: 500 parts of 2,4-dichlorotoluene (b.p.=198° to 200° C.) and 10 parts of anhydrous aluminum chloride were charged into a 1-liter four-necked flask provided with a reflux condenser, a thermometer, a stirrer and a dropping funnel. 397 parts of bromine was added dropwisely at 30° to 40° C. over a period of 5 hours. The reaction liquid was washed with warm water followed by separating the water layer, and then the oil layer was cooled. The separated crystals were filtered off, recrystallized from methanol to obtain 295 parts of 2,4-dichloro-5-bromotoluene having a melting point of 82.5° to 84.0° C. provided with a reflux condenser The reaction liquid was washed with warm water by separating the water layer the oil layer was cooled The separated crystals were filtered off recrystallized from methanol

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

Procedure: 500 parts of 2,4-dichlorotoluene (b.p.=198° to 200° C.) and 10 parts of anhydrous aluminum chloride were charged into a 1-liter four-necked flask provided with a reflux condenser, a thermometer, a stirrer and a dropping funnel. 397 parts of bromine was added dropwisely at 30° to 40° C. over a period of 5 hours. The reaction liquid was washed with warm water followed by separating the water layer, and then the oil layer was cooled. The separated crystals were filtered off, recrystallized from methanol to obtain 295 parts of 2,4-dichloro-5-bromotoluene having a melting point of 82.5° to 84.0° C. provided with a reflux condenser The reaction liquid was washed with warm water by separating the water layer the oil layer was cooled The separated crystals were filtered off recrystallized from methanol

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

Procedure: To stirred fuming nitric acid (200 ml) at 0° C. was added slowly 2,4-dichlorotoluene (50 g, 0.3mole). Upon completion of addition, the reaction mixture was stirred for one hour, then was poured into water (100 ml). A yellow precipitate was collected by filtration to yield 62.0 g of 2,4-dichloro-5-nitrotoluene, m.p. 40°-44° C. Upon completion of addition A yellow precipitate was collected by filtration

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

Procedure: To a mixture of 32 g of 4,6-dichlorotoluene and 0.3 g of anhydrous FeCl3, add, with stirring, 10 g of bromine in 1 g portions while maintaining a temperature of 20°-25° C. Add thereto a solution of 22 g of bromine in 100 mL of CCl4 slowly while maintaining a temperature of 20°-25° C. After the addition of bromine is complete, stir the mixture so formed for 15 min, and dilute the reaction mixture with 200 mL of CH2Cl2, and wash the organic solution with 5% aqueous sodium thiosulfate. Dry the organic layer over anhydrous K2CO3, filter, and evaporate to a residue. Recrystallize the residue from CH3CN to give 32 g of 2-bromo-4,6-dichlorotoluene, mp 84°-5° C. add Add stir the mixture so formed for 15 min wash the organic solution with 5% aqueous sodium thiosulfate Dry the organic layer over anhydrous K2CO3 filter evaporate to a residue Recrystallize the residue from CH3CN

Conditions: temp:160.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a 600 cc Hastoloy C autoclave was charged 48.52 g of a crude chlorination mixture containing 10.93% 2,4-dichlorotoluene, 70.39% α,2,4-trichlorotoluene, 18.52% α,α,2,4-tetrachlorotoluene, 0.10% α,α,2,4-pentachlorotoluene (the percentages represent gas chromatograph area percents), 39 g of sodium bicarbonate and 146 ml of water. The autoclave was flushed with nitrogen and pressure tested to 1500 psig. The autoclave was then vented to atmospheric pressure and heated. The temperature was increased to 160° C. and maintained for two hours. The pressure increased from atmosphere pressure to between 200 and 400 psig. After two hours, the autoclave was cooled to 80° C., vented and the product removed. After separation of the aqueous phase, the crude aldehyde mixture was flash distilled affording 11.84% 2,4-dichlorotoluene, 16.94% 2,4-dichlorobenzaldehyde and 71.21% 2,4-dichlorobenzyl alcohol. To a 600 cc Hastoloy C autoclave was charged 48.52 g of a crude chlorination mixture The autoclave was flushed with nitrogen and pressure heated maintained for two hours The pressure increased from atmosphere pressure to between 200 and 400 psig the autoclave was cooled to 80° C. the product removed After separation of the aqueous phase distilled