N-(4-bromophenyl)-3-oxobutanamide

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

Procedure: A mixture of 3.00 g (0.0117 moles) of N-(4-bromophenyl)-3-oxobutyramide and 6 ml concentrated sulfuric acid was stirred and heated to 95°-100° C. (H2O bath) for 11/2 hours. The resulting solution was poured onto an ice/H2O mixture to yield a white crystalline product. The crystals were collected and taken up in 200 ml absolute ethanol. The volume was reduced to 150 ml followed by chilling; crystals were isolated (0.71 g 25.6%), mp 292°-299° C. Anal. Calcd. for C10H8BrNO: C, 50.45; H, 3.39; N, 5.88; Br, 33.56. Found: C, 50.28; H, 3.44; N, 5.83; Br, 33.68. A TLC of the product on silica showed Rf 0.18 with ethyl acetate eluent. to yield a white crystalline product The crystals were collected by chilling crystals were isolated (0.71 g 25.6%), mp 292°-299° C

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

Procedure: A mixture of 3.00 g (0.0117 moles) of N-(4-bromophenyl)-3-oxobutyramide and 6 ml concentrated sulfuric acid was stirred and heated to 95°-100° C. (H2O bath) for 11/2 hours. The resulting solution was poured onto an ice/H2O mixture to yield a white crystalline product. The crystals were collected and taken up in 200 ml absolute ethanol. The volume was reduced to 150 ml followed by chilling; crystals were isolated (0.71 g 25.6%), mp 292°-299° C. Anal. Calcd. for C10H8BrNO: C, 50.45; H, 3.39; N, 5.88; Br, 33.56. Found: C, 50.28; H, 3.44; N, 5.83; Br, 33.68. A TLC of the product on silica showed Rf 0.18 with ethyl acetate eluent. to yield a white crystalline product The crystals were collected by chilling crystals were isolated (0.71 g 25.6%), mp 292°-299° C

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 34.14 g (0.200 moles) of 4-bromoaniline in 130 ml toluene under N2, 18.00 g (0.220 moles) of diketene was added dropwise over a 10 minute period followed by 15 ml of toluene. The temperature rose to 80° C. during the addition; the solution was then refluxed 20 minutes, cooled to 55° C. and 60 ml of petroleum ether added. An immediate precipitation occurred. The tan-white crystals were filtered and washed with three 100 ml portions of 1:1 toluene/petroleum ether. The product was taken up in hot absolute ethanol and crystallisation induced by addition of toluene to the ethanolic solution. Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%) and had Rf 0.69 on silica TLC with ethyl acetate; mp 135.8°-137.2° C. Anal. Calcd. for C10H10BrNO2 : C, 46.90; H, 3.94; N, 5.47; Br, 31.20. Found: C, 47.13; H, 4.00; N, 5.46; Br, 31.31. The temperature rose to 80° C. during the addition the solution was then refluxed 20 minutes An immediate precipitation The tan-white crystals were filtered washed with three 100 ml portions of 1:1 toluene/petroleum ether crystallisation induced by addition of toluene to the ethanolic solution Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%)

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 34.14 g (0.200 moles) of 4-bromoaniline in 130 ml toluene under N2, 18.00 g (0.220 moles) of diketene was added dropwise over a 10 minute period followed by 15 ml of toluene. The temperature rose to 80° C. during the addition; the solution was then refluxed 20 minutes, cooled to 55° C. and 60 ml of petroleum ether added. An immediate precipitation occurred. The tan-white crystals were filtered and washed with three 100 ml portions of 1:1 toluene/petroleum ether. The product was taken up in hot absolute ethanol and crystallisation induced by addition of toluene to the ethanolic solution. Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%) and had Rf 0.69 on silica TLC with ethyl acetate; mp 135.8°-137.2° C. Anal. Calcd. for C10H10BrNO2 : C, 46.90; H, 3.94; N, 5.47; Br, 31.20. Found: C, 47.13; H, 4.00; N, 5.46; Br, 31.31. The temperature rose to 80° C. during the addition the solution was then refluxed 20 minutes An immediate precipitation The tan-white crystals were filtered washed with three 100 ml portions of 1:1 toluene/petroleum ether crystallisation induced by addition of toluene to the ethanolic solution Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%)

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

Procedure: A solution of 50.0 g (195 mmol) of N-(4-bromophenyl)-3-oxobutyramide in 217 mL of concentrated sulfuric acid was heated to 120° C. for 1 hour. After cooling to RT, the reaction solution was added to 1.5 L of ice water, stirred for 30 minutes, and the precipitate formed was filtered and washed with 4 L of water. Subsequently it was dried at 35° C. in the circulating air dryer until a constant weight was achieved. Yield: 24.0 g (52% of theoretical); C10H8BrNO (M=238.081); calc.: molpeak (M+H)+: 238/240 (Br); found: molpeak (M+H)+: 238/240 (Br); HPLC-MS: 4.8 minutes (method B). the precipitate formed was filtered washed with 4 L of water Subsequently it was dried at 35° C. in the circulating air dryer until a constant weight 4.8 minutes (method B)

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

Procedure: A solution of 25.72 mL (336 mmol) of diketene in 100 mL of toluene was added dropwise at 90° C. to a solution of 51.0 g (288 mmol) of 4-bromoaniline in 200 mL of toluene and the reaction mixture was kept at this temperature for 5 hours. The reaction solution was cooled in the ice bath, and the precipitate formed was filtered and washed with toluene until the product was virtually colorless. Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained. Yield: 50.0 g (68% of theoretical); C10H10BrNO2 (M=256.096); calc.: molpeak (M+H)+: 256/258 (Br); found: molpeak (M+H)+: 256/258 (Br); HPLC-MS: 4.7 minutes (method B). the precipitate formed was filtered washed with toluene until the product Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained 4.7 minutes (method B)

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

Procedure: A solution of 25.72 mL (336 mmol) of diketene in 100 mL of toluene was added dropwise at 90° C. to a solution of 51.0 g (288 mmol) of 4-bromoaniline in 200 mL of toluene and the reaction mixture was kept at this temperature for 5 hours. The reaction solution was cooled in the ice bath, and the precipitate formed was filtered and washed with toluene until the product was virtually colorless. Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained. Yield: 50.0 g (68% of theoretical); C10H10BrNO2 (M=256.096); calc.: molpeak (M+H)+: 256/258 (Br); found: molpeak (M+H)+: 256/258 (Br); HPLC-MS: 4.7 minutes (method B). the precipitate formed was filtered washed with toluene until the product Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained 4.7 minutes (method B)

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

Procedure: A mixture of 3.00 g (0.0117 moles) of N-(4-bromophenyl)-3-oxobutyramide and 6 ml concentrated sulfuric acid was stirred and heated to 95°-100° C. (H2O bath) for 11/2 hours. The resulting solution was poured onto an ice/H2O mixture to yield a white crystalline product. The crystals were collected and taken up in 200 ml absolute ethanol. The volume was reduced to 150 ml followed by chilling; crystals were isolated (0.71 g 25.6%), mp 292°-299° C. Anal. Calcd. for C10H8BrNO: C, 50.45; H, 3.39; N, 5.88; Br, 33.56. Found: C, 50.28; H, 3.44; N, 5.83; Br, 33.68. A TLC of the product on silica showed Rf 0.18 with ethyl acetate eluent. to yield a white crystalline product The crystals were collected by chilling crystals were isolated (0.71 g 25.6%), mp 292°-299° C

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 34.14 g (0.200 moles) of 4-bromoaniline in 130 ml toluene under N2, 18.00 g (0.220 moles) of diketene was added dropwise over a 10 minute period followed by 15 ml of toluene. The temperature rose to 80° C. during the addition; the solution was then refluxed 20 minutes, cooled to 55° C. and 60 ml of petroleum ether added. An immediate precipitation occurred. The tan-white crystals were filtered and washed with three 100 ml portions of 1:1 toluene/petroleum ether. The product was taken up in hot absolute ethanol and crystallisation induced by addition of toluene to the ethanolic solution. Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%) and had Rf 0.69 on silica TLC with ethyl acetate; mp 135.8°-137.2° C. Anal. Calcd. for C10H10BrNO2 : C, 46.90; H, 3.94; N, 5.47; Br, 31.20. Found: C, 47.13; H, 4.00; N, 5.46; Br, 31.31. The temperature rose to 80° C. during the addition the solution was then refluxed 20 minutes An immediate precipitation The tan-white crystals were filtered washed with three 100 ml portions of 1:1 toluene/petroleum ether crystallisation induced by addition of toluene to the ethanolic solution Three crops of crystals from the ethanol/toluene solvent system gave 22.90 g (43%)

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

Procedure: A solution of 25.72 mL (336 mmol) of diketene in 100 mL of toluene is added dropwise at 90° C. to a solution of 51.0 g (288 mmol) of 4-bromoaniline in 200 mL of toluene and the reaction mixture is kept for 5 hours at this temperature. The reaction solution is cooled in the ice bath, and the precipitate formed is filtered and then washed with toluene until the product is virtually colorless. Subsequently it is dried at 50° C. in the circulating air dryer until the weight is constant. Yield: 50.0 g (68% of theoretical); C10H10BrNO2 (M=256.096); calc.: molpeak (M+H)+: 256/258 (Br); found: molpeak (M+H)+: 256/258 (Br); HPLC-MS: 4.7 min (method B). the precipitate formed is filtered washed with toluene until the product Subsequently it is dried at 50° C. in the circulating air dryer until the weight 4.7 min (method B)

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

Procedure: A solution of 50.0 g (195 mmol) of N-(4-bromophenyl)-3-oxobutyramide in 217 mL of concentrated sulfuric acid was heated to 120° C. for 1 hour. After cooling to RT, the reaction solution was added to 1.5 L of ice water, stirred for 30 minutes, and the precipitate formed was filtered and washed with 4 L of water. Subsequently it was dried at 35° C. in the circulating air dryer until a constant weight was achieved. Yield: 24.0 g (52% of theoretical); C10H8BrNO (M=238.081); calc.: molpeak (M+H)+: 238/240 (Br); found: molpeak (M+H)+: 238/240 (Br); HPLC-MS: 4.8 minutes (method B). the precipitate formed was filtered washed with 4 L of water Subsequently it was dried at 35° C. in the circulating air dryer until a constant weight 4.8 minutes (method B)

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

Procedure: A solution of 25.72 mL (336 mmol) of diketene in 100 mL of toluene was added dropwise at 90° C. to a solution of 51.0 g (288 mmol) of 4-bromoaniline in 200 mL of toluene and the reaction mixture was kept at this temperature for 5 hours. The reaction solution was cooled in the ice bath, and the precipitate formed was filtered and washed with toluene until the product was virtually colorless. Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained. Yield: 50.0 g (68% of theoretical); C10H10BrNO2 (M=256.096); calc.: molpeak (M+H)+: 256/258 (Br); found: molpeak (M+H)+: 256/258 (Br); HPLC-MS: 4.7 minutes (method B). the precipitate formed was filtered washed with toluene until the product Subsequently it was dried at 50° C. in the circulating air dryer until a constant weight was obtained 4.7 minutes (method B)