Pivaloyl chloride → HCID 178495557, compound

HRID 444865Notes

Reaction equation

HRID 444865 reaction equation
[Li+].C[Si]([N-][Si](C)(C)C)(C)C.[CH3:11][O:12][CH:13]=[CH:14][C:15](=[O:17])[CH3:16].[C:18](Cl)(=[O:23])[C:19]([CH3:22])([CH3:21])[CH3:20]>C1COCC1>[OH:23][C:18]([C:19]([CH3:22])([CH3:21])[CH3:20])=[CH:16][C:15](=[O:17])[CH:14]=[CH:13][O:12][CH3:11]

Participants

5

Reactant 3

HCID 62493Pivaloyl chlorideHCID 942973-Buten-2-one, 4-methoxy-HCID 2733832Lithium Hexamethyldisilazide

Product 1

HCID 178495557HCID 178495557, compoundYield 74.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-78 °C

Procedure

LiHMDS (1M in THF, 100 mL, 2 eq) is added dropwise to a cold (−78° C.) solution of 4-methoxy-3-buten-2-one (10 mL, 100 mmol, 2 eq) in THF (400 mL). After a 30 min stirring at −78° C., a solution of pivaloyl chloride (6.12 mL, 50 mmol) in THF (100 mL) is added. The resulting mixture is allowed to warm to it over 2 h and quenched by addition of a saturated solution of NH4Cl. THF is removed under vacuum. The concentrated mixture is extracted with Et2O. The organic phase is washed with brine, dried (Na2SO4), filtered and concentrated. The residue is purified by silica gel column chromatography (Hex/EtOAc, 1:0→85:15) to afford 6.83 g of the title compound as a yellow oil: ESI-MS: 185.1 [M+H]+; TLC: Rf=0.87 (Hex/EtOAc, 1:1).

Workup

  1. temperatureto warm to it over 2 h
  2. customquenched by addition of a saturated solution of NH4Cl
  3. customTHF is removed under vacuum
  4. extractionThe concentrated mixture is extracted with Et2O
  5. washThe organic phase is washed with brine
  6. dry with materialdried (Na2SO4)
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customThe residue is purified by silica gel column chromatography (Hex/EtOAc, 1:0→85:15)

Sources & evidence

ORD record
ord-52b81041d7c4443198c6a06b75171240
Source dataset
uspto-grants-2013_07
Patent number
US08476268B2

Reaction notes

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