Ethyl 4-oxocyclohexanecarboxylate → Ethyl 4-methylidenecyclohexane-1-carboxylate

HRID 2202675Notes

Reaction equation

HRID 2202675 reaction equation
[CH3:1][Si]([N-][Si](C)(C)C)(C)C.[Li+].O=[C:12]1[CH2:17][CH2:16][CH:15]([C:18]([O:20][CH2:21][CH3:22])=[O:19])[CH2:14][CH2:13]1>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C1COCC1>[CH2:1]=[C:12]1[CH2:17][CH2:16][CH:15]([C:18]([O:20][CH2:21][CH3:22])=[O:19])[CH2:14][CH2:13]1

Participants

5

Reactant 2

HCID 317638Ethyl 4-oxocyclohexanecarboxylateHCID 2733832Lithium Hexamethyldisilazide

Product 1

HCID 15151435Ethyl 4-methylidenecyclohexane-1-carboxylate

Reagents, catalysts & solvents 2

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent2×

Procedure

Lithium bis(trimethylsilyl)amide (1.0 M in THF, 15 mL, 15 mmol) was added dropwisely to a stirred solution of methyltriphenylphosphonium bromide (5.36 g, 15 mmol) in THF (50 mL) at 0° C. and stirred for 40 min at the same temperature. A solution of ethyl 4-oxocyclohexanecarboxylate (2.04 g, 12 mmol) in THF (20 mL) was added slowly at 0° C. and stirred for 2 h from 0° C. to room temperature. The reaction was quenched with saturated NH4Cl aq. and extracted with hexane. The collected organic layer was dried over MgSO4 and concentrated under reduced pressure. The solvent (100 mL, hexane/Et2O=5/1) was added to the residue and stirred for 30 min. The suspension was filtrated. The filtrate was concentrated under reduced pressure. The residue was purified by silicagel chromatography (5% EtOAc/hexane as eluent) to provide compound A122-1 (1.478 g, 73%) as a colorless oil.

Workup

  1. stirringstirred for 2 h from 0° C. to room temperature
  2. customThe reaction was quenched with saturated NH4Cl aq.
  3. extractionextracted with hexane
  4. dry with materialThe collected organic layer was dried over MgSO4
  5. concentrationconcentrated under reduced pressure
  6. additionThe solvent (100 mL, hexane/Et2O=5/1) was added to the residue
  7. stirringstirred for 30 min
  8. filtrationThe suspension was filtrated
  9. concentrationThe filtrate was concentrated under reduced pressure
  10. customThe residue was purified by silicagel chromatography (5% EtOAc/hexane as eluent)
  11. customto provide compound A122-1 (1.478 g, 73%) as a colorless oil

Sources & evidence

ORD record
ord-9e69b1429d804f1499d8e396cfade2d7
Source dataset
uspto-grants-2016_06
Patent number
US09365522B2

Reaction notes

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