Stannous chloride dihydrate → Methyl 5-amino-1-benzothiophene-2-carboxylate

HRID 343883Notes

Reaction equation

HRID 343883 reaction equation
[N+:1]([C:4]1[CH:16]=[CH:15][C:7]2[S:8][C:9]([C:11]([O:13][CH3:14])=[O:12])=[CH:10][C:6]=2[CH:5]=1)([O-])=O.O.O.[Sn](Cl)Cl>C(O)C>[NH2:1][C:4]1[CH:16]=[CH:15][C:7]2[S:8][C:9]([C:11]([O:13][CH3:14])=[O:12])=[CH:10][C:6]=2[CH:5]=1

Participants

4

Reactant 2

HCID 61436Stannous chloride dihydrateHCID 1489057Methyl 5-nitro-1-benzothiophene-2-carboxylate

Product 1

HCID 2824064Methyl 5-amino-1-benzothiophene-2-carboxylateYield 98%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

In a 250 ml round-bottomed flask fitted with a Teflon stirrer and a reflux condenser, methyl 5-nitrobenzo[b]thiophene-2-carboxylate (10 g, 42.18 mmole) was dissolved in ethanol (100 ml). Tin (II) chloride dihydrate (5 equivalents, 47.60 g, 211 mmole) was added in one lot and the resulting slurry was reluxed for 18 hours while being stirred. The reaction mixture was cooled to room temperature, transferred to a 2000 ml Erlenmeyer flask, and carefully quenched with 5% sodium bicarbonate solution (aprroximately 700 ml) until effervescense was no longer detected. The resulting precipitate was filtered off and air-dried. The dried solid was dissolved in hot ethanol (500 ml), and filtered to remove undissolved material. The filtrate was evaporated in vacuo to give 8.564 g (96%) of methyl 5-aminobenzo[b]thiophene-2-carboxylate.

Workup

  1. customIn a 250 ml round-bottomed flask fitted with a Teflon stirrer and a reflux condenser
  2. customcarefully quenched with 5% sodium bicarbonate solution (aprroximately 700 ml) until effervescense
  3. filtrationThe resulting precipitate was filtered off
  4. customair-dried
  5. dissolutionThe dried solid was dissolved in hot ethanol (500 ml)
  6. filtrationfiltered
  7. customto remove undissolved material
  8. customThe filtrate was evaporated in vacuo

Sources & evidence

ORD record
ord-00766e8be3ff416a9f7ce3244beb3683
Source dataset
uspto-grants-1999_01
Patent number
US05863936

Reaction notes

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