1,4-二溴-2,3-丁二酮

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo 2,3-butanedione, 60 ml (0.36 M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo 2,3-butanedione, 60 ml (0.36 M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Following the procedure of Example 1, condensation of 1,4-dibromo-2,3-butanedione with 1,2-diamino-4-chlorobenzene yielded 2,3-bis(bromomethyl)-6-chloroquinoxaline, m.p. 149°-150° C.; 1H NMR (CDCl3, 400 MHz): δ4.89 and 4.90 (singlets, 4H, CH2), 7.74 (dd, J1 =8.9 Hz, J2 =2.3 Hz, 1H, H-7), 8.01 (d, J=8.9 Hz, 1H, H-8), 8.07 (d, J=2.3 Hz, 1H, H-5).

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Following the procedure of Example 1, condensation of 1,4-dibromo-2,3-butanedione with 1,2-diamino-4,5-dichlorobenzene yielded 2,3-bis(bromomethyl)-6,7-dichloro-quinoxaline, m.p. 154°-156° C.; 1H NMR (CDCl3, 200 MHz): δ4.86 (s, 4H, CH2), 8.18 (s, 2H, ArH).

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Following the procedure of Example 1, 1,4-dibromo-2,3-butanedione is condensed with 2,3-diaminonaphthalene to obtain 2,3-bis(bromomethyl)benzo[g]quinoxaline, m.p. 190°-191° C.; 1H NMR (DMSO-d6, 400 MHz): δ5.07 (s, 4H, CH2), 7.68 and 8.26 (double doublets, 4H, H-7 and H-8, H-6 and H-9, resp.), 8.78 (s, 2H, H-5 and H-10).

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 1,2-phenylenediamine (0.1 mole, 10.8 g) and 1,4-dibromo-2,3-butanedione (0.1 mole, 24.4 g) was refluxed in benzene (200 mL) using a Dean-Stark trap for one hour. The reaction mixture was then evaporated to dryness in vacuo and the residue flash chromatographed on silica gel (15:1). Elution with 15% hexane/chloroform afforded 29.38 g of 2,3-bis(bromomethyl)quinoxaline, m.p. 150°-151° C.; 1H NMR (CDCl3, 200 MHz): δ4.92 (s, 4H, CH2), 7.8 (m, 2H, ArH), 8.05 (m, 2H, ArH). for one hour The reaction mixture was then evaporated to dryness in vacuo the residue flash chromatographed on silica gel (15:1) Elution with 15% hexane/chloroform

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 1,2-phenylenediamine (0.1 mole, 10.8 g) and 1,4-dibromo-2,3-butanedione (0.1 mole, 24.4 g) was refluxed in benzene (200 mL) using a Dean-Stark trap for one hour. The reaction mixture was then evaporated to dryness in vacuo and the residue flash chromatographed on silica gel (15:1). Elution with 15% hexane/chloroform afforded 29.38 g of 2,3-bis(bromomethyl)quinoxaline, m.p. 150°-151° C.; 1H NMR (CDCl3, 200 MHz): δ4.92 (s, 4H, CH2), 7.8 (m, 2H, ArH), 8.05 (m, 2H, ArH). for one hour The reaction mixture was then evaporated to dryness in vacuo the residue flash chromatographed on silica gel (15:1) Elution with 15% hexane/chloroform

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo 2,3-butanedione, 60 ml (0.36 M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo-2,3-butanedione, 60 ml (0.36M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo-2,3-butanedione, 60 ml (0.36 M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A mixture of 40 g (0.164 mol) of 1,4-dibromo-2,3-butanedione, 60 ml (0.36 M) of triethylorthoformate, and 2 ml of concentrated sulfuric acid was stirred at room temperature for 14 hours, then diluted with 600 ml of chloroform, and washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution. The organic solution was dried over anhydrous sodium sulfate filtered, and evaporated leaving an oil. The oil was taken up into 300 ml of hexane and filtered to remove some insoluble material. The hexane filtrate was cooled in a dry-ice/acetone bath, and the resulting precipitate was collected by filtration and dried to give 44 g (84%) of 1,4-dibromo-2,2-diethoxy-3-butanone as a white crystalline solid, mp 40°-41.5°; nmr (CDCl3) (δ): 4.50 (s, 2H); 3.6-3.2 (m, 6H); 1.22 (t, 6H). washed successively with 100 ml portions of water, 0.5 N hydrochloric acid and saturated sodium chloride solution The organic solution was dried over anhydrous sodium sulfate filtered evaporated leaving an oil filtered to remove some insoluble material The hexane filtrate was cooled in a dry-ice/acetone bath the resulting precipitate was collected by filtration dried

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Following the procedure of Example 1, condensation of 1,4-dibromo-2,3-butanedione with 1,2-diamino-4-chlorobenzene yielded 2,3-bis(bromomethyl)-6-chloroquinoxaline, m.p. 149°-150° C.; 1H NMR (CDCl3, 400 MHz): δ4.89 and 4.90 (singlets, 4H, CH2), 7.74 (dd, J1 =8.9 Hz, J2 =2.3 Hz, 1H, H-7), 8.01 (d, J=8.9 Hz, 1H, H-8), 8.07 (d, J=2.3 Hz, 1H, H-5).