Bromine → Dimethyl 3-bromothieno-[2,3-b]pyridine-5,6-dicarboxylate

HRID 256118Notes

Reaction equation

HRID 256118 reaction equation
[Br:1]Br.[CH3:3][O:4][C:5]([C:7]1[CH:8]=[C:9]2[CH:19]=[CH:18][S:17][C:10]2=[N:11][C:12]=1[C:13]([O:15][CH3:16])=[O:14])=[O:6].C([O-])(=O)C.[Na+]>C(O)(=O)C.O>[Br:1][C:19]1[C:9]2[C:10](=[N:11][C:12]([C:13]([O:15][CH3:16])=[O:14])=[C:7]([C:5]([O:4][CH3:3])=[O:6])[CH:8]=2)[S:17][CH:18]=1

Participants

6

Reactant 3

HCID 24408Bromine2×HCID 517045Sodium Acetate2×HCID 13729652Dimethyl thieno[2,3-b]pyridine-5,6-dicarboxylate

Product 1

HCID 13752488Dimethyl 3-bromothieno-[2,3-b]pyridine-5,6-dicarboxylate

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolvent3×HCID 962WaterSolvent

Conditions

Temperature
75 °C

Procedure

Bromine (0.33 , 0.00206 mol) in acetic acid (8 mL) is added to a stirred solution of dimethylthieno[2,3-b]pyridine-5,6-dicarboxylate (0.5 g, 0.00187 mol) in acetic acid containing sodium acetate (0.31 g, 0.00377 mol) at 40° C. The reaction mixture is heated at 75° C. for 18 hours. Evaluation of the mixture by tlc (silica gel) indicated incomplete reaction. Additional bromine (0.33 g) in acetic acid and sodium acetate (0.31 g) is added and heating at 75° C. continued for six hours. The reaction mixture is diluted with water and extracted into ethyl acetate. The separated organic layer is dried over anhydrous MgSO4, filtered, and the filtrate concentrated to an oil which solidifies on standing. Crystallization of the crude product from ethyl acetate-hexanes yields the dimethyl 3-bromothieno[2,3-b]pyridine-5,6-dicarboxylate as white needles mp 86°-87.5° C.

Workup

  1. customreaction
  2. temperatureheating at 75° C.
  3. extractionextracted into ethyl acetate
  4. dry with materialThe separated organic layer is dried over anhydrous MgSO4
  5. filtrationfiltered
  6. concentrationthe filtrate concentrated to an oil which
  7. customCrystallization of the crude product from ethyl acetate-hexanes

Sources & evidence

ORD record
ord-2a9418463f784f709ba1bfbdca491b5a
Source dataset
uspto-grants-1987_10
Patent number
US04701208

Reaction notes

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