Sodium borohydride → tert-Butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylate

HRID 1943596Notes

Reaction equation

HRID 1943596 reaction equation
[BH4-].[Na+].[O:3]=[C:4]1[CH2:17][C:6]2([CH2:9][N:8]([C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])[CH2:7]2)[CH2:5]1>CO>[OH:3][CH:4]1[CH2:5][C:6]2([CH2:9][N:8]([C:10]([O:12][C:13]([CH3:15])([CH3:14])[CH3:16])=[O:11])[CH2:7]2)[CH2:17]1

Participants

4

Reactant 2

HCID 4311764Sodium borohydrideHCID 52333005tert-Butyl 6-oxo-2-azaspiro(3.3)heptane-2-carboxylate

Product 1

HCID 52987765tert-Butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylateYield 96.4%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

0.494 g (13.06 mmoles) of sodium borohydride is added in portions at 0° C. to a solution of 2.30 g (10.89 mmoles) of tert-butyl 6-oxo-2-aza-spiro[3.3]-heptane-2-carboxylate, obtained in stage 10.2, in 55 ml of methanol. The reaction mixture is stirred for 1 hr at ambient temperature. After evaporation of the solvent, water is added to the reaction mixture, the aqueous phase is separated, it is extracted several times with dichloromethane, and the combined organic phases are washed with a saturated aqueous solution of sodium chloride, dried over sodium sulphate and the filtrate is concentrated under reduced pressure. After crystallisation of the residue in diisopropyl ether, filtration of the solid obtained and drying under vacuum at 60° C., 2.24 g of product are obtained in the form of a beige powder.

Workup

  1. customAfter evaporation of the solvent, water
  2. additionis added to the reaction mixture
  3. customthe aqueous phase is separated
  4. extractionit is extracted several times with dichloromethane
  5. washthe combined organic phases are washed with a saturated aqueous solution of sodium chloride
  6. dry with materialdried over sodium sulphate
  7. concentrationthe filtrate is concentrated under reduced pressure
  8. customAfter crystallisation of the residue in diisopropyl ether
  9. filtrationfiltration of the solid
  10. customobtained
  11. customdrying under vacuum at 60° C.

Sources & evidence

ORD record
ord-948839cdea534bba9b3369148721ace5
Source dataset
uspto-grants-2013_03
Patent number
US08394787B2

Reaction notes

Loading…