Carbon tetrabromide → 3-Bromo-pyrrolidine-1-carboxylic acid tert-butyl ester

HRID 42135Notes

Reaction equation

HRID 42135 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][CH:10](O)[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(Br)(Br)(Br)[Br:34]>C1COCC1>[C:1]([O:5][C:6]([N:8]1[CH2:12][CH2:11][CH:10]([Br:34])[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

5

Reactant 3

HCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 44169391-Boc-3-pyrrolidinol

Product 1

HCID 426142173-Bromo-pyrrolidine-1-carboxylic acid tert-butyl esterYield 80%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a solution of (RS) 1-tert-butoxycarbonyl-3-pyrrolidinol (Prepn. 3) (3.00 g) in THF (90 mL), triphenylphosphine (12.4 g) was added, then a solution of CBr4 (15.7 g) in THF (90 mL) was dropped and the mixture stirred overnight at room temperature. The organic solvent was evaporated and the residue was extracted with EtOAc (4×50 mL). The combined organic extracts were washed with H2O, dried over Na2SO4 and evaporated to dryness. The residue was purified by flash chromatography (SiO2, cyclohexane/EtOAc 80/20) to give (RS) 1-tert-butoxycarbonyl-3-bromopyrrolidine in 80% yield as yellow oil. 1H-NMR (300 MHz, DMSO-d6, ppm from TMS): δ 4.85 (1H, m), 3.70-3.59 (1H, m), 3.55-2.10 (5H, m), 1.35 (9H, s).

Workup

  1. customThe organic solvent was evaporated
  2. extractionthe residue was extracted with EtOAc (4×50 mL)
  3. washThe combined organic extracts were washed with H2O
  4. dry with materialdried over Na2SO4
  5. customevaporated to dryness
  6. customThe residue was purified by flash chromatography (SiO2, cyclohexane/EtOAc 80/20)

Sources & evidence

ORD record
ord-35f8915470a1418a81cdc37cf87deb5f
Source dataset
uspto-grants-2013_09
Patent number
US08536160B2

Reaction notes

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