p-Toluenesulfonic acid → tert-butyl 4-(1-acetyl-1H-indol-3-yl)piperazine-1-carboxylate

HRID 641887

Reaction equation

HRID 641887 reaction equation
C(O[C:5]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[N:7]([C:14](=[O:16])[CH3:15])[CH:6]=1)(=O)C.[N:17]1([C:23]([O:25][C:26]([CH3:29])([CH3:28])[CH3:27])=[O:24])[CH2:22][CH2:21][NH:20][CH2:19][CH2:18]1.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[C:14]([N:7]1[C:8]2[C:13](=[CH:12][CH:11]=[CH:10][CH:9]=2)[C:5]([N:20]2[CH2:19][CH2:18][N:17]([C:23]([O:25][C:26]([CH3:29])([CH3:28])[CH3:27])=[O:24])[CH2:22][CH2:21]2)=[CH:6]1)(=[O:16])[CH3:15]

Participants

5

Reactant 3

HCID 6101p-Toluenesulfonic acidHCID 143452tert-Butyl piperazine-1-carboxylateHCID 5836021-Acetyl-1H-indol-3-yl acetate

Product 1

HCID 59259291tert-butyl 4-(1-acetyl-1H-indol-3-yl)piperazine-1-carboxylate

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
120 °C

Procedure

Into a 150 mL sealed tube was placed a solution of 1-acetyl-1H-indol-3-yl acetate (2.5 g, 11.51 mmol) in toluene (80 mL). To this was added tert-butyl piperazine-1-carboxylate (10.71 g, 57.55 mmol). To the mixture was added p-toluenesulfonic acid (400 mg, 2.33 mmol). The resulting solution was allowed to react, with stirring, overnight while the temperature was maintained at 120° C. in a bath of oil. The reaction progress was monitored by TLC (ethyl acetate/petroleum ether=1:1). The mixture was concentrated by evaporation under vacuum using a rotary evaporator. The resulting solution was diluted with 200 mL of ethyl acetate. The resulting mixture was washed 3 times with 200 mL of NaCl(aq.). The mixture was dried over Na2SO4. The residue was purified by eluting through a column with a 10:1 petroleum ether/ethyl acetate solvent system. This resulted in 2.9 g (72%) of tert-butyl 4-(1-acetyl-1H-indol-3-yl)piperazine-1-carboxylate as a purple solid.

Workup

  1. customInto a 150 mL sealed tube
  2. customto react
  3. concentrationThe mixture was concentrated by evaporation under vacuum
  4. customa rotary evaporator
  5. additionThe resulting solution was diluted with 200 mL of ethyl acetate
  6. washThe resulting mixture was washed 3 times with 200 mL of NaCl(aq.)
  7. dry with materialThe mixture was dried over Na2SO4
  8. customThe residue was purified
  9. washby eluting through a column with a 10:1 petroleum ether/ethyl acetate solvent system
  10. customThis resulted in 2.9 g (72%) of tert-butyl 4-(1-acetyl-1H-indol-3-yl)piperazine-1-carboxylate as a purple solid

Sources & evidence

ORD record
ord-aac31a08a2a542ecaefc79b1615cad5f
Source dataset
uspto-grants-2010_04
Patent number
US07696229B2

Linked notes

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