Hydrochloric Acid → Methyl 4-bromo-5-cyano-3-methylthiophene-2-carboxylate

HRID 1723925Notes

Reaction equation

HRID 1723925 reaction equation
Cl.[NH2:2]O.[Br:4][C:5]1[C:6]([CH3:16])=[C:7]([C:12]([O:14][CH3:15])=[O:13])[S:8][C:9]=1[CH:10]=O.FC(F)(F)C(OC(=O)C(F)(F)F)=O.Cl>C(#N)C.N1C=CC=CC=1.C(OCC)(=O)C>[Br:4][C:5]1[C:6]([CH3:16])=[C:7]([C:12]([O:14][CH3:15])=[O:13])[S:8][C:9]=1[C:10]#[N:2]

Participants

8

Reactant 4

HCID 313Hydrochloric AcidHCID 9845Trifluoroacetic anhydrideHCID 443297Hydroxyamine hydrochlorideHCID 71378553Methyl 4-bromo-5-formyl-3-methylthiophene-2-carboxylate

Product 1

HCID 66570703Methyl 4-bromo-5-cyano-3-methylthiophene-2-carboxylateYield 91.5%

Reagents, catalysts & solvents 3

HCID 1049PyridineSolventHCID 6342AcetonitrileSolventHCID 8857Ethyl AcetateSolvent

Procedure

Hydroxylamine hydrochloride (5 g, 72 mmol) was added to a solution of methyl 4-bromo-5-formyl-3-methylthiophene-2-carboxylate (16.5 g, 63 mmol) in acetonitrile (175 mL) and pyridine (30 mL). The resulting solution was stirred at room temperature for 2 h, then trifluoroacetic anhydride (21.3 mL, 153 mmol). After 3 h the reaction mixture was poured into ethyl acetate and aqueous hydrochloric acid. The organic layer was separated, washed with hydrochloric acid and water, dried over sodium sulphate and evaporated. The resulting raw material was triturated with 90 mL of a water/ethyl alcohol mixture (1:1) and dried under vacuum to give 15 g of the title compound, used in the following step without further purification.

Workup

  1. customThe organic layer was separated
  2. washwashed with hydrochloric acid and water
  3. dry with materialdried over sodium sulphate
  4. customevaporated
  5. customThe resulting raw material was triturated with 90 mL of a water/ethyl alcohol mixture (1:1)
  6. customdried under vacuum

Sources & evidence

ORD record
ord-bf84f696bcbc4a7fa3c39ce7c7c169b3
Source dataset
uspto-grants-2009_02
Patent number
US07485661B2

Reaction notes

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