tert-Butyl carbazate → N-(1-carboethoxy-3-phenylpropyl)-N'-BOC-hydrazine

HRID 979961Notes

Reaction equation

HRID 979961 reaction equation
[C:1]1([CH2:7][CH2:8][C:9](=O)[C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[C:16]([O:20][C:21](=[O:24])[NH:22][NH2:23])([CH3:19])([CH3:18])[CH3:17].C([BH3-])#N.[Na+]>C1COCC1>[C:10]([CH:9]([NH:23][NH:22][C:21]([O:20][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:24])[CH2:8][CH2:7][C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1)([O:12][CH2:13][CH3:14])=[O:11]

Participants

5

Reactant 3

HCID 70091tert-Butyl carbazateHCID 562087Ethyl alpha-oxobenzenebutanoateHCID 5003444Sodium cyanoborohydride

Product 1

HCID 20223112N-(1-carboethoxy-3-phenylpropyl)-N'-BOC-hydrazine

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of ethyl 4-phenyl-2-oxobutanoate (2.06 g; 10 mmol) and t-butylcarbazate (1.32 g; 10 mmol) in THF (50 ml) can be warmed at reflux for 8 hours. Solvent can be evaporated and the residue taken up in anhydrous ethanol (25 ml). Sodium cyanoborohydride (0.31 g; 5 mmol) can be added, and the solution stirred for 4 hrs. The residue, after evaporation, can be stirred with EtOAc (50 ml) and hydrochloric acid (0.5 N: 20 ml) for 30 minutes. The aqueous layer can be neutralized by addition of K2CO3 and extracted with EtOAc (3×25 ml). The combined organic portions can be washed with H2O and brine and dried (MgSO4). The residue, upon evaporation, can be purified by chromatography on silica gel, affording N-(1-carboethoxy-3-phenylpropyl)-N'-BOC-hydrazine. An ice-cold solution of the above hydrazine in trifluoroacetic acid can be allowed to stand for 1 hr. Removal of solvent can provide hydrazine (56) as the trifluoroacetic acid salt.

Workup

  1. temperatureat reflux for 8 hours
  2. customSolvent can be evaporated
  3. customThe residue, after evaporation
  4. stirringcan be stirred with EtOAc (50 ml) and hydrochloric acid (0.5 N: 20 ml) for 30 minutes
  5. additionThe aqueous layer can be neutralized by addition of K2CO3
  6. extractionextracted with EtOAc (3×25 ml)
  7. washThe combined organic portions can be washed with H2O and brine
  8. dry with materialdried (MgSO4)
  9. customThe residue, upon evaporation
  10. customcan be purified by chromatography on silica gel

Sources & evidence

ORD record
ord-50bdb97ed0254bb39485c10a6fb6bb2e
Source dataset
uspto-grants-1987_01
Patent number
US04634715

Reaction notes

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