Potassium Bromide → 3-Oxo-azetidine-1-carboxylic acid tert-butyl ester

HRID 1966179Notes

Reaction equation

HRID 1966179 reaction equation
[OH:1][CH:2]1[CH2:5][N:4]([C:6]([O:8][C:9]([CH3:12])([CH3:11])[CH3:10])=[O:7])[CH2:3]1.[Br-].[K+].C(=O)(O)[O-].[Na+].Cl[O-].[Na+]>C(OCC)(=O)C.O.CC1(C)N([O])C(C)(C)CCC1>[O:1]=[C:2]1[CH2:5][N:4]([C:6]([O:8][C:9]([CH3:12])([CH3:11])[CH3:10])=[O:7])[CH2:3]1

Participants

8

Reactant 4

HCID 253877Potassium BromideHCID 516892Sodium BicarbonateHCID 2756801Tert-butyl 3-hydroxyazetidine-1-carboxylateHCID 23665760Sodium Hypochlorite3×

Product 1

HCID 15194043-Oxo-azetidine-1-carboxylic acid tert-butyl esterYield 97%

Reagents, catalysts & solvents 3

HCID 2724126TempoCatalystHCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of tert-butyl 3-hydroxyazetidine-1-carboxylate (24, 50 g, 289 mmol) in ethyl acetate (400 mL) was cooled to 0° C. The resulting solution was then treated with solid TEMPO (0.5 g, 3.2 mmol, 0.011 equiv) and a solution of potassium bromide (KBr, 3.9 g, 33.2 mmol, 0.115 equiv) in water (60 mL) at 0-5° C. While keeping the reaction temperature between 0-5° C. a solution of saturated aqueous sodium bicarbonate (NaHCO3, 450 mL) and an aqueous sodium hypochlorite solution (NaClO, 10-13% available chlorine, 450 mL) were added. Once the solution of sodium hypochlorite was added, the color of the reaction mixture was changed immediately. When additional amount of sodium hypochlorite solution was added, the color of the reaction mixture was gradually faded. When TLC showed that all of the starting material was consumed, the color of the reaction mixture was no longer changed. The reaction mixture was then diluted with ethyl acetate (EtOAc, 500 mL) and two layers were separated. The organic layer was washed with water (500 mL) and the saturated aqueous sodium chloride solution (500 mL) and dried over sodium sulfate (Na2SO4). The solvent was then removed under reduced pressure to give the crude product, tert-butyl 3-oxoazetidine-1-carboxylate (7, 48 g, 49.47 g theoretical, 97% yield), which was found to be sufficiently pure and was used directly in the subsequent reaction without further purification. For crude 7: 1H NMR (CDCl3, 300 MHz), δ 4.65 (s, 4H), 1.42 (s, 9H) ppm.

Workup

  1. customat 0-5° C
  2. custombetween 0-5° C.
  3. customwas consumed
  4. additionThe reaction mixture was then diluted with ethyl acetate (EtOAc, 500 mL) and two layers
  5. customwere separated
  6. washThe organic layer was washed with water (500 mL)
  7. dry with materialthe saturated aqueous sodium chloride solution (500 mL) and dried over sodium sulfate (Na2SO4)
  8. customThe solvent was then removed under reduced pressure

Sources & evidence

ORD record
ord-e25c65308f9d48229a9a05a746715448
Source dataset
uspto-grants-2013_04
Patent number
US08420629B2

Reaction notes

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