Piperazine → Thieno[2,3-b]pyridin-3-amine

HRID 326988

Reaction equation

HRID 326988 reaction equation
COC([C:5]1[S:13][C:8]2=[N:9][CH:10]=[CH:11][CH:12]=[C:7]2[C:6]=1[NH2:14])=O.N1CCNCC1.CN1CCCC1=O>O>[S:13]1[C:8]2=[N:9][CH:10]=[CH:11][CH:12]=[C:7]2[C:6]([NH2:14])=[CH:5]1

Participants

5

Reactant 3

HCID 4837PiperazineHCID 13387N-methyl-2-pyrrolidoneHCID 2820896Methyl 3-aminothieno(2,3-b)pyridine-2-carboxylate

Product 1

HCID 289923Thieno[2,3-b]pyridin-3-amineYield 86%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
145 °C

Procedure

A mixture of 3-aminothieno[2,3-b]pyridine-2-carboxylic acid methyl ester (8.00 g), piperazine (6.70 g), and N-methyl-2-pyrrolidinone (80 ml) was heated to 145° C. for 3 hr, under a nitrogen atmosphere. The solution was allowed to cool, diluted with water (400 ml), and extracted with ethyl acetate. The combined extracts were washed with water and brine dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated to give 4.94 g (86.0%) of residual thieno[2,3-b]pyridine-3-amine.

Workup

  1. temperatureto cool
  2. extractionextracted with ethyl acetate
  3. washThe combined extracts were washed with water and brine
  4. dry with materialdried over anhydrous sodium sulfate
  5. filtrationfiltered
  6. concentrationthe filtrate was concentrated

Sources & evidence

ORD record
ord-5d479739d7d443faab94979cf3a2641f
Source dataset
uspto-grants-1993_12
Patent number
US05272148

Linked notes

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