p-Toluenesulfonic acid → (RS)-2-methyl-5-oxo-2-phenylcyclohexene-1-carboxylic acid

HRID 324673Notes

Reaction equation

HRID 324673 reaction equation
O[C:2]1([C:16]([OH:18])=[O:17])[CH2:7][C:6](=[O:8])[CH2:5][CH2:4][C:3]1([CH3:15])[C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH3:15][C:3]1([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)[CH2:4][CH2:5][C:6](=[O:8])[CH:7]=[C:2]1[C:16]([OH:18])=[O:17]

Participants

4

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 22004689(1RS,2RS)-1-hydroxy-2-methyl-5-oxo-2-phenylcyclohexane-1-carboxylic acid

Product 1

HCID 20647081(RS)-2-methyl-5-oxo-2-phenylcyclohexene-1-carboxylic acidYield 69.1%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
0 °C

Procedure

4.4 g (17.6 mmol) of (1RS,2RS)-1-hydroxy-2-methyl-5-oxo-2-phenylcyclohexane-1-carboxylic acid were heated at reflux for one hour in 100 cm3 of toluene in the presence of 0.34 g of para-toluenesulphonic acid. The reaction mixture was cooled to 0° C. and the precipitate formed was filtered off, washed with ethyl ether and then dried at 50° C. 2.8 g (69%) of (RS)-2-methyl-5-oxo-2-phenylcyclohexene-1-carboxylic acid were thus obtained in the form of a pink solid, the characteristics of which were as follows:

Workup

  1. customthe precipitate formed
  2. filtrationwas filtered off
  3. washwashed with ethyl ether
  4. customdried at 50° C

Sources & evidence

ORD record
ord-eed134c5bc184f2f86a0a42ec8e5f77d
Source dataset
uspto-grants-2001_04
Patent number
US06218406B1

Reaction notes

Loading…