Water → 1-Cyclopentene-1-acetic acid, 2,3,3-trimethyl-

HRID 345266Notes

Reaction equation

HRID 345266 reaction equation
[CH3:1][C:2]1[C:6]([CH3:8])([CH3:7])[CH2:5][CH2:4][C:3]=1[CH2:9][CH:10]=[O:11].S(=O)(=O)(O)[OH:13].O.[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=O.[Na+].[Na+]>CC(C)=O>[CH3:1][C:2]1[C:6]([CH3:7])([CH3:8])[CH2:5][CH2:4][C:3]=1[CH2:9][C:10]([OH:13])=[O:11]

Participants

6

Conditions

Temperature
0 °C

Procedure

A solution was made of β-campholenic aldehyde (150 g) in acetone (2 liters) and cooled to 0° C. Oxidizing agent was prepared from 169 ml conc. sulfuric acid, 736 ml water and 292 g of sodium dichromate (Na2Cr2O7.2H2O). The reagent (375 ml) was added to the solution at 0° C. over a period of 30 minutes. After an additional 15 minutes at 0° C. the acetone was removed by decantation and the residual chromium salts were washed with an additional 200 ml acetone. The combined acetone solution was concentrated, the residue taken up in 10% aqueous sodium hydroxide (1 liter) and the solution washed with CH2Cl2 (2×1 liter). The aqueous phase was acidified with 25% sulfuric acid followed by extraction with CH2Cl2 (2×1 liter). Concentration of the dried CH2Cl2 solution yielded an oil (73 g) which was distilled under reduced pressure to give 53 g of a yellowish liquid; bp 102° C. @ 1.1 mm Hg; crystallized upon standing; analysis: (CW 20M fused silica column, 190° C.) 96% β-campholenic acid.

Workup

  1. customAfter an additional 15 minutes at 0° C. the acetone was removed by decantation
  2. washthe residual chromium salts were washed with an additional 200 ml acetone
  3. concentrationThe combined acetone solution was concentrated
  4. washthe solution washed with CH2Cl2 (2×1 liter)
  5. extractionfollowed by extraction with CH2Cl2 (2×1 liter)

Sources & evidence

ORD record
ord-9cad72a81af54bd3bc14c40b376eade5
Source dataset
uspto-grants-1991_10
Patent number
US05057158

Reaction notes

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