2,2-Dimethyl-3-heptanol → 2,2-Dimethyl-3-heptanone

HRID 1754169Notes

Reaction equation

HRID 1754169 reaction equation
[CH3:1][C:2]([CH3:10])([CH:4]([OH:9])[CH2:5][CH2:6][CH2:7][CH3:8])[CH3:3].[Cr](Cl)([O-])(=O)=O.[NH+]1C=CC=CC=1>C(Cl)Cl>[CH3:1][C:2]([CH3:10])([C:4](=[O:9])[CH2:5][CH2:6][CH2:7][CH3:8])[CH3:3]

Participants

4

Reactant 2

HCID 1405432,2-Dimethyl-3-heptanolHCID 178418287HCID 178418287, compound

Product 1

HCID 1404722,2-Dimethyl-3-heptanoneYield 89.2%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

2,2-Dimethyl-heptan-3-ol (0.23 mol) was dissolved in 350 mL of CH2Cl2 in a 500 mL round bottom flask with a magnetic stirbar. The flask was partially cooled with ice. 76.6 g (0.355 mol) of pyridinium chlorochromate was added, while vigorously stirring. The reaction turned black and warmed up slightly. The reaction mixture was stirred at room temperature for 24 hours. The solution was decanted away from the black sludge, which was rinsed with hexane. The organic extracts were combined and chromatographed directly on silica gel. (Note: only silica has been found to trap and remove the reduced non-reacted chromium compounds). The product, 2,2-dimethyl-heptan-3-one, eluted with CH2Cl2/hexane and in a subsequent 10% ethyl acetate/hexane fraction to yield 29.19 g of product at 88% yield. 1H NMR (CDCl3, 500 MHz) δ (ppm): 2.48 (t, 2H), 1.54 (m, 2H), 1.28 (m, 2H), 1.13 (s, 9H), 0.90 (m, 3H).

Workup

  1. temperatureThe flask was partially cooled with ice
  2. temperaturewarmed up slightly
  3. stirringThe reaction mixture was stirred at room temperature for 24 hours
  4. customThe solution was decanted away from the black sludge, which
  5. washwas rinsed with hexane
  6. customchromatographed directly on silica gel
  7. custom(Note: only silica has been found to trap
  8. customremove the reduced non-reacted chromium compounds)
  9. washThe product, 2,2-dimethyl-heptan-3-one, eluted with CH2Cl2/hexane and in a subsequent 10% ethyl acetate/hexane fraction

Sources & evidence

ORD record
ord-e97b7042d7f04fe89d2c0a5cb7a20745
Source dataset
uspto-grants-2015_10
Patent number
US09169210B2

Reaction notes

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