Acetic Acid → tert-Butyl 4-cyclopropylpiperazine-1-carboxylate

HRID 1437232Notes

Reaction equation

HRID 1437232 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].C(O[C:17]1(O[Si](C)(C)C)[CH2:19][CH2:18]1)C.C(O)(=O)C.C([BH3-])#N.[Na+]>CO.C(OCC)C>[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([CH:17]2[CH2:19][CH2:18]2)[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

7

Reactant 4

HCID 176Acetic AcidHCID 143452tert-Butyl piperazine-1-carboxylateHCID 2734686(1-Ethoxycyclopropoxy)trimethylsilaneHCID 5003444Sodium cyanoborohydride

Product 1

HCID 20294524tert-Butyl 4-cyclopropylpiperazine-1-carboxylateYield 71%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 3283Diethyl EtherSolvent

Procedure

Piperazine-1-carboxylic acid tert-butyl ester (1.87 g), [(1-ethoxycyclopropyl)oxy]trimethylsilane (8.05 mL), and acetic acid (5.72 mL) were dissolved in methanol (60 mL). To the resultant solution, sodium cyanoborohydride (1.89 g) was added at room temperature, followed by stirring for 5 days. Diethyl ether was added to the residue obtained by removal through evaporation of the reaction solvent under reduced pressure, and insoluble matter was filtered off. The filtrate was partitioned by addition of aqueous 1N sodium hydroxide thereto. The organic layer was washed with saturated brine, and then dried over magnesium sulfate anhydrate, followed by filtration. The solvent was evaporated under reduced pressure. The residue was purified through silica gel column chromatography (hexane-ethyl acetate), to thereby give the title compound as a solid (1.62 g, 71%).

Workup

  1. customobtained by removal through evaporation of the reaction solvent under reduced pressure, and insoluble matter
  2. filtrationwas filtered off
  3. customThe filtrate was partitioned by addition of aqueous 1N sodium hydroxide
  4. washThe organic layer was washed with saturated brine
  5. dry with materialdried over magnesium sulfate anhydrate
  6. filtrationfollowed by filtration
  7. customThe solvent was evaporated under reduced pressure
  8. customThe residue was purified through silica gel column chromatography (hexane-ethyl acetate)

Sources & evidence

ORD record
ord-ba5d1e9c2020473cb238c63d6d851666
Source dataset
uspto-grants-2009_11
Patent number
US07622471B2

Reaction notes

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