methyl 4-(4-chlorophenyl)-2,4-dioxobutanoate

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

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

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5-110.5° C. 1H NMR (CDCl3/300 M/z) δ 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4'-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt. % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0 ° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5°-110.5 ° C. 1H NMR (CDCl3 /300 MHz) δ 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0 ° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4'-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt. % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0 ° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5°-110.5 ° C. 1H NMR (CDCl3 /300 MHz) δ 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0 ° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5-110.5° C. 1H NMR (CDCl3/300 MHz) δ7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5-110.5° C. 1H NMR (CDCl3/300 MHz) δ7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were charged to a 500 mL round-bottom flask, with provisions made for magnetic stirring, and diluted with methanol (300 mL). Sodium methoxide (25% in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours. The reaction became an insoluble mass during this time. The solid was mechanically broken up, then concentrated hydrochloric acid (70 mL) was added, and the white suspension was stirred vigorously at room temperature for sixty minutes. The suspension was cooled to 0° C. and held for 30 minutes. The soild was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl 4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: 1H NMR (CDCl3/300 MHz) 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). the white suspension was stirred vigorously at room temperature for sixty minutes The suspension was cooled to 0° C. held for 30 minutes The soild was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4'-chloroacetophenone (20.0 g, 0.129 mol) were charged to a 500 mL round-bottom flask, with provisions made for magnetic stirring, and diluted with methanol (300 mL). Sodium methoxide (25% in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours. The reaction became an insoluble mass during this time. The solid was mechanically broken up, then concentrated hydrochloric acid (70 mL) was added, and the white suspension was stirred vigorously at room temperature for sixty minutes. The suspension was cooled to 0° C. and held for 30 minutes. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl 4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: 1H NMR (CDCl3 /300 MHz) 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). the white suspension was stirred vigorously at room temperature for sixty minutes The suspension was cooled to 0° C. held for 30 minutes The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (23.6 g, 200 mmol) was placed in a 500 mL three-necked round bottom flask, and dissolved in diethyl ether (200 mL). To the stirred solution was added 25% sodium methoxide in methanol (48 mL, 210 mmol) via an addition funnel over a 2 minute period. Next, 4'-chloroacetophenone (25.94 g, 200 mmol) was dissolved in diethyl ether (50 mL), and added to the reaction dropwise over 3 minutes. After stirring overnight (18 hours), 1N HCl (400 mL) and ethyl acetate (750 mL) were added. The organic layer was collected, washed with brine (350 mL), dried over MgSO4, filtered, and concentrated in vacuo to give 45.7 g of a yellow solid. The solid was recrystallized from ethyl acetate and iso-octane to give 23 g (48%) of the dione: mp 108.5°-110.5° C. added to the reaction dropwise over 3 minutes were added The organic layer was collected washed with brine (350 mL) dried over MgSO4 filtered concentrated in vacuo

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5–110.5° C. 1H NMR (CDCl3/300 MHz) δ 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying

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

Procedure: Dimethyl oxalate (15.27 g, 0.129 mol) and 4′-chloroacetophenone (20.0 g, 0.129 mol) were diluted with methanol (300 mL) and sodium methoxide (25 wt % in methanol, 70 mL) was added in one portion. The reaction was stirred at room temperature for 16 hours (the reaction became an insoluble mass during this time). The solid was mechanically broken up, hydrochloric acid (conc. 70 mL) was added, and the white suspension was stirred vigorously at room temperature for 1 hour. The suspension was cooled to 0° C. and held for 0.5 hour. The solid was filtered, and the filter cake was washed with cold water (100 mL). Upon drying, methyl-4-[4-(chloro)phenyl]-2,4-dioxobutanoate was obtained (16.94 g, 54.4%) as the enol: mp 108.5–110.5° C. 1H NMR (CDCl3/300 MHz) δ 7.94 (d, J=8.66 Hz, 2H), 7.48 (d, J=8.66 Hz, 2H), 7.04 (s, 1H), 3.95 (s, 3H), 3.48 (s, 1H). was added in one portion the white suspension was stirred vigorously at room temperature for 1 hour The suspension was cooled to 0° C. held for 0.5 hour The solid was filtered the filter cake was washed with cold water (100 mL) Upon drying