Water → Benzyl 3-oxocyclopentanecarboxylate

HRID 920807

Reaction equation

HRID 920807 reaction equation
[O:1]=[C:2]1[CH2:6][CH2:5][CH:4]([C:7]([OH:9])=[O:8])[CH2:3]1.C([O-])([O-])=O.[K+].[K+].[CH2:16](Br)[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1.O>CN(C=O)C>[O:1]=[C:2]1[CH2:6][CH2:5][CH:4]([C:7]([O:9][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[O:8])[CH2:3]1

Participants

6

Reactant 4

HCID 962WaterHCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 2277983-Oxocyclopentanecarboxylic acid

Product 1

HCID 14530748Benzyl 3-oxocyclopentanecarboxylateYield 82.2%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a stirred solution of 3-oxocyclopentanecarboxylic acid (1.5 g, 11.71 mmol) in DMF (20 mL) was added K2CO3 (1.780 g, 12.88 mmol) followed by benzyl bromide (1.360 mL, 11.71 mmol) under nitrogen. The reaction mixture was then stirred for 18 h at RT. The reaction mixture was poured into water (100 mL) and extracted with ethyl acetate (2×100 mL). The combined organic layer was washed with brine, dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude compound was purified by silica gel chromatography (12 g REDISEP® column, eluting with 20% EtOAc in hexane). Fractions containing the product were combined and evaporated to afford Intermediate 332A (2.1 g, 78% yield) as an oil. 1H NMR (400 MHz, chloroform-d) δ ppm 7.42-7.31 (m, 5H), 5.16 (s, 2H), 3.22-3.12 (m, 1H), 2.58-2.45 (m, 2H), 2.44-2.29 (m, 2H), 2.23 (s, 2H).

Workup

  1. extractionextracted with ethyl acetate (2×100 mL)
  2. washThe combined organic layer was washed with brine
  3. dry with materialdried over anhydrous Na2SO4
  4. concentrationconcentrated under reduced pressure
  5. customThe crude compound was purified by silica gel chromatography (12 g REDISEP® column, eluting with 20% EtOAc in hexane)
  6. additionFractions containing the product
  7. customevaporated

Sources & evidence

ORD record
ord-d81bda1319c94cd5864fac294002afdf
Source dataset
uspto-grants-2016_03
Patent number
US09273058B2

Linked notes

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