Methanol → 4-(3-Amino-2-hydroxy-phenyl)-thiophene-2-carboxylic acid hydrobromide

HRID 2271450Notes

Reaction equation

HRID 2271450 reaction equation
Br.[NH2:2][C:3]1[C:4]([O:17]C)=[C:5]([C:9]2[CH:10]=[C:11]([C:14]([OH:16])=[O:15])[S:12][CH:13]=2)[CH:6]=[CH:7][CH:8]=1.B(Br)(Br)[Br:20].CO>ClCCl>[BrH:20].[NH2:2][C:3]1[C:4]([OH:17])=[C:5]([C:9]2[CH:10]=[C:11]([C:14]([OH:16])=[O:15])[S:12][CH:13]=2)[CH:6]=[CH:7][CH:8]=1

Participants

5

Reactant 3

HCID 887MethanolHCID 25134Boron tribromideHCID 574838484-(3-Amino-2-methoxy-phenyl)-thiophene-2-carboxylic acid hydrobromide

Product 1

HCID 574838464-(3-Amino-2-hydroxy-phenyl)-thiophene-2-carboxylic acid hydrobromideYield 17.5%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

4-(3-Amino-2-methoxy-phenyl)-thiophene-2-carboxylic acid hydrobromide 19b (360 mg, 1.45 mmol) was dissolved in 5 mL of dichloromethane followed by dropwise addition of boron tribromide (2.8 mL, 5.6 mmol). The reaction mixture was reacted at room temperature for 4.5 hours. The reaction mixture was added with 5 mL of methanol and concentrated under reduced pressure. The residue was diluted with 10 mL of ethyl acetate and stirred for 0.5 hours. The mixture was filtered and the filter cake was dried to obtain the title compound 4-(3-amino-2-hydroxy-phenyl)-thiophene-2-carboxylic acid hydrobromide 19c (80 mg, yield 17.5%) as a grey solid.

Workup

  1. customThe reaction mixture was reacted at room temperature for 4.5 hours
  2. concentrationconcentrated under reduced pressure
  3. additionThe residue was diluted with 10 mL of ethyl acetate
  4. filtrationThe mixture was filtered
  5. customthe filter cake was dried

Sources & evidence

ORD record
ord-b51b34059dbc4dc5a7f1257de5b209e4
Source dataset
uspto-grants-2015_09
Patent number
US09120762B2

Reaction notes

Loading…