Tetrahydrofuran → 1,1-Dimethylethyl 4-(4-amino-3-methylphenyl)-1-piperazinecarboxylate

HRID 415064Notes

Reaction equation

HRID 415064 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4]([N:11]2[CH2:16][CH2:15][N:14]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:13][CH2:12]2)[CH:5]=[CH:6][C:7]=1[N+:8]([O-])=O.O1CCCC1.C([O-])=O.[NH4+]>[Fe].O>[NH2:8][C:7]1[CH:6]=[CH:5][C:4]([N:11]2[CH2:16][CH2:15][N:14]([C:17]([O:19][C:20]([CH3:22])([CH3:21])[CH3:23])=[O:18])[CH2:13][CH2:12]2)=[CH:3][C:2]=1[CH3:1]

Participants

6

Reactant 3

HCID 8028TetrahydrofuranHCID 2723923Ammonium formateHCID 53763997Tert-butyl 4-(3-methyl-4-nitrophenyl)piperazine-1-carboxylate

Product 1

HCID 445223981,1-Dimethylethyl 4-(4-amino-3-methylphenyl)-1-piperazinecarboxylateYield 97.7%

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 962WaterSolvent

Conditions

Temperature
75 °C

Procedure

tert-Butyl 4-(3-methyl-4-nitrophenyl)piperazine-1-carboxylate (1.25 g, 3.90 mmoles), 1 equivalent), tetrahydrofuran (10 ml), water (10 ml), iron dust (1.09 g, 19.5 mmoles, 5 equivalents), and ammonium formate (1.23 g, 19.5 mmoles, 5 equivalents) were combined and heated, with stirring to 75° C. for 12 hours (overnight). The hot mixture was filtered through a plug of Celite and washed with ethyl acetate. The filtrate was evaporated under reduced pressure and extracted with ethyl acetate. The ethyl acetate solution was washed with water and saturated sodium chloride solution. The ethyl acetate solution was dried over anhydrous sodium sulfate, filtered and evaporated under reduced pressure to give 1.11 g of tert-butyl 4-(4-amino-3-methylphenyl)piperazine-1-carboxylate. 1H-NMR (400 MHz, CDCl3), δ 6.47 (d, 1H), 6.16 (d, 1H), 6.14 (d, 1H), 5.85 (bs, 2H), 3.35 (m, 4H), 3.19 (m, 4H), 2.35 (s, 3H), 1.42 (s, 9H). MS (EI) for C16H25N3O2, 292 (MH+).

Workup

  1. temperatureheated
  2. filtrationThe hot mixture was filtered through a plug of Celite
  3. washwashed with ethyl acetate
  4. customThe filtrate was evaporated under reduced pressure
  5. extractionextracted with ethyl acetate
  6. washThe ethyl acetate solution was washed with water and saturated sodium chloride solution
  7. dry with materialThe ethyl acetate solution was dried over anhydrous sodium sulfate
  8. filtrationfiltered
  9. customevaporated under reduced pressure

Sources & evidence

ORD record
ord-71cec95d07b348578e6a4e9a89860c58
Source dataset
uspto-grants-2012_01
Patent number
US08088767B2

Reaction notes

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