6-bromo-7-chloro-3,4-dihydro-1H-quinoxalin-2-one

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

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

Procedure: To a stirred suspension of 6-bromo-7-chloro-3,4-dihydroquinoxaline-2(1H)-one (0.06 g, 0.23 mmol, as obtained above) in CF3COOH (0.5 mL) was added fuming HNO3 (0.02 mL, 0.46 mmol) and the resulting reddish yellow suspension was stirred at room temperature overnight The cream colored suspension so obtained was poured into ice (2.5 mL) and the precipitated solid was filtered, washed with water (1.0 mL), and dried under vacuum to afford 0.049 g (70%) of the title compound as a cream colored powder. 1H NMR (DMSO-d6): δ 7.577 (s, 1H), 8.251 (s, 1H), 12.879 (s, 1H). The crude product was used as such for the final reaction. so obtained the precipitated solid was filtered washed with water (1.0 mL) dried under vacuum

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

Procedure: A solution of N-(5′-bromo-4′-chloro-2′-nitrophenyl)glycine sodium salt (0.255 g, 0.824 mmol, as prepared above) and tin (II) chloride dihydrate (0.560 g, 2.48 mmol, Aldrich, used as received) in ethanol (6 mL) was refluxed for 3 h. It was then cooled to room temperature and allowed to stand overnight at room temperature. The white solid was filtered and dried to yield 0.038 g (18%) of the pure (1H NMR) title compound as white flakes; m.p. 230-232° C.; 1H NMR (DMSO-d6): δ 3.732 (s, 2H), 6.371 (s, 1H), 6.830 (s, 1H), 6.912 (s, 1H), 10.437 (s, 1H). Extraction of the filtrate with ethyl acetate (30 mL) gave 0.136 g (68%) more product for a combined yield of 86%. The product was used as such for the next reaction. The white solid was filtered dried

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

Procedure: A solution of N-(5′-bromo-4′-chloro-2′-nitrophenyl)glycine sodium salt (0.255 g, 0.824 mmol, as prepared above) and tin (II) chloride dihydrate (0.560 g, 2.48 mmol, Aldrich, used as received) in ethanol (6 mL) was refluxed for 3 h. It was then cooled to room temperature and allowed to stand overnight at room temperature. The white solid was filtered and dried to yield 0.038 g (18%) of the pure (1H NMR) title compound as white flakes; m.p. 230-232° C.; 1H NMR (DMSO-d6): δ 3.732 (s, 2H), 6.371 (s, 1H), 6.830 (s, 1H), 6.912 (s, 1H), 10.437 (s, 1H). Extraction of the filtrate with ethyl acetate (30 mL) gave 0.136 g (68%) more product for a combined yield of 86%. The product was used as such for the next reaction. The white solid was filtered dried

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

Procedure: To a stirred suspension of 6-bromo-7-chloro-3,4-dihydroquinoxaline-2(1H)-one (0.06 g, 0.23 mmol) in CF3COOH (0.5 mL) was added fuming HNO3 (0.02 mL, 0.46 mmol) and the resulting reddish yellow suspension was stirred at r.t. overnight. The cream colored suspension so obtained was poured into ice (2.5 mL) and the precipitated solid was filtered, washed with water (1.0 mL) and dried under vacuum to afford 0.049 g (70%) of title compound as a cream colored powder which contained ~10% impurity (1H NMR integration); 1H NMR (DMSO-d6): δ7.577 (s, 1H), 8.251 (s, 1H), 12.879 (s, 1H). The crude product was used for the next reaction. The cream colored suspension so obtained the precipitated solid was filtered washed with water (1.0 mL) dried under vacuum

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

Procedure: A solution of N-(5-bromo-4-chloro-2-nitrophenyl)glycine (0.255 g, 0.824 mmol) and tin (II) chloride dihydrate (0.560 g, 2.48 Aldrich, used as received) was refluxed for 3 h. It was then cooled to r.t. and allowed to stand overnight at r.t. The white solid was filtered and dried to yield 0.038 g (18%) of pure title compound as white flakes; m.p. 230°-232° C.; 1H NMR (DMSO-d6):3.732 (s, 2H), 6.371 (s, 1H), 6.830 (s, 1H), 6.912 (s, 1H), 10.437 (s, 1H). Extraction of the filtrate with ethyl acetate (30 mL) gave 0.136 g (68%) more product to get a combined yield of 81%. The white solid was filtered dried

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

Procedure: To a stirred suspension of 6-bromo-7-chloro-3,4-dihydroquinoxaline-2(1H)-one (0.06 g, 0.23 mmol) in CF3COOH (0.5 mL) was added fuming HNO3 (0.02 mL, 0.46 mmol) and the resulting reddish yellow suspension was stirred at r.t. overnight. The cream colored suspension so obtained was poured into ice (2.5 mL) and the precipitated solid was filtered, washed with water (1.0 mL) and dried under vacuum to afford 0.049 g (70%) of title compound as a cream colored powder which contained ~10% impurity (1H NMR integration); 1H NMR (DMSO-d6): δ7.577 (s, 1H), 8.251 (s, 1H), 12.879 (s, 1H). The crude product was used for the next reaction. The cream colored suspension so obtained the precipitated solid was filtered washed with water (1.0 mL) dried under vacuum

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

Procedure: A solution of N-(5-bromo-4-chloro-2-nitrophenyl)glycine (0.255 g, 0.824 mmol) and tin (II) chloride dihydrate (0.560 g, 2.48 Aldrich, used as received) was refluxed for 3 h. It was then cooled to r.t. and allowed to stand overnight at r.t. The whim solid was filtered and dried to yield 0.038 g (18%) of pure title compound as white flakes; m.p. 230°-232° C.; 1H NMR (DMSO-d6): 3.732 (s, 2H), 6.371 (s, 1H), 6.830 (s, 1H), 6.912 (s, 1H), 10.437 (s, 1H). Extraction of the filtrate with ethyl acetate (30 mL) gave 0.136 g (68%) more product to get a combined yield of 81%. The whim solid was filtered dried

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

Procedure: To a stirred suspension of 6-bromo-7-chloro-3,4-dihydroquinoxaline-2(1H)-one (0.06 g, 0.23 mmol) in CF3COOH (0.5 mL) was added fuming HNO3 (0.02 mL, 0.46 mmol) and the resulting reddish yellow suspension was stirred at r.t. overnight. The cream colored suspension so obtained was poured into ice (2.5 mL) and the precipitated solid was filtered, washed with water (1.0 mL) and dried under vacuum to afford 0.049 g (70%) of title compound as a cream colored powder which contained ~10% impurity (1H NMR integration); 1H NMR (DMSO-d6): δ 7.577 (s, 1H), 8.251 (s, 1H), 12.879 (s, 1H). The crude product was used for the next reaction. The cream colored suspension so obtained the precipitated solid was filtered washed with water (1.0 mL) dried under vacuum

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

Procedure: A solution of N-(5-bromo-4-chloro-2-nitrophenyl)glycine (0.255 g, 0.824 mmol) and tin (II) chloride dihydrate (0.560 g, 2.48 Aldrich, used as received) was refluxed for 3 h. It was then cooled to r.t. and allowed to stand overnight at r.t. The white solid was filtered and dried to yield 0.038 g (18%) of pure title compound as white flakes; m.p. 230°-232° C.; 1H NMR (DMSO-d6): 3.732 (s, 2H), 6.371 (s, 1H), 6.830 (s, 1H), 6.912 (s, 1H), 10.437 (s, 1H). Extraction of the filtrate with ethyl acetate (30 mL) gave 0.136 g (68%) more product to get a combined yield of 81%. The white solid was filtered dried

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

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

Procedure: To a stirred suspension of 6-bromo-7-chloro-3,4-dihydroquinoxaline-2(1H)-one (0.06 g, 0.23 mmol) in CF3COOH (0.5 mL) was added fuming HNO3 (0.02 mL, 0.46 mmol) and the resulting reddish yellow suspension was stirred at r.t. overnight. The cream colored suspension so obtained was poured into ice (2.5 mL) and the precipitated solid was filtered, washed with water (1.0 mL) and dried under vacuum to afford 0.049 g (70%) of title compound as a cream colored powder which contained ~10% impurity (1H NMR integration); 1H NMR (DMSO-d6): δ7.577 (s, 1H), 8.251 (s, 1H), 12.879 (s, 1H). The crude product was used for the next reaction. The cream colored suspension so obtained the precipitated solid was filtered washed with water (1.0 mL) dried under vacuum