Hydrochloric Acid → (1R*,5S*)-3-(3,5-dimethyl-biphenyl-4-yl)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dione

HRID 341647Notes

Reaction equation

HRID 341647 reaction equation
[CH3:1][C@@:2]12[O:9][C@@H:6]([CH2:7][CH2:8]1)[C:5](=[O:10])[CH2:4][C:3]2=[O:11].C(Cl)(Cl)Cl.[C:16]([O-])(=O)C.C([O-])(=O)C.C([O-])(=O)C.Cl[C:29]1([Pb+3])[C:34]([CH3:35])=[CH:33][C:32]([C:36]2[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=2)=[CH:31][CH2:30]1.Cl>CN(C)C1C=CN=CC=1.C1(C)C=CC=CC=1>[CH3:16][C:30]1[CH:31]=[C:32]([C:36]2[CH:41]=[CH:40][CH:39]=[CH:38][CH:37]=2)[CH:33]=[C:34]([CH3:35])[C:29]=1[CH:4]1[C:5](=[O:10])[C@H:6]2[O:9][C@:2]([CH3:1])([CH2:8][CH2:7]2)[C:3]1=[O:11]

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 6212ChloroformHCID 67533518(1R*,5S*)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dioneHCID 178476521[Diacetyloxy-(1-chloro-2-methyl-4-phenylcyclohexa-2,4-dien-1-yl)plumbyl] acetate

Product 1

HCID 68731583(1R*,5S*)-3-(3,5-dimethyl-biphenyl-4-yl)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dioneYield 32.7%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 1140TolueneSolvent

Conditions

Temperature
80 °C

Procedure

(1R*,5S*)-1-Methyl-8-oxabicyclo[3.2.1]octane-2,4-dione (0.20 g, 1.298 mmol) and 4-dimethylaminopyridine (0.792 g, 6.49 mmol) are added to a mixture of chloroform (4 ml) and toluene (1 ml). The reaction mixture is flushed with nitrogen for 15 minutes at ambient temperature. 4-Chloro-3-methylbiphen-4-yllead triacetate (0.836 g, 1.428 mmol) is added in one portion and the reaction mixture is stirred and heated to 80° C. under an atmosphere of nitrogen for 1 hour. The reaction mixture is cooled to room temperature, acidified to pH 1 with 2N aqueous hydrochloric acid, filtered through a plug of diatomaceous earth and the two phases are separated. The aqueous phase is extracted with dichloromethane (2×5 ml), the organic phases are combined, washed with water, and dried over anhydrous sodium sulfate. The mixture is filtered, and the filtrate is evaporated under reduced pressure. The residue is purified by column chromatography on silica gel to give (1R*,5S*)-3-(3,5-dimethyl-biphenyl-4-yl)-1-methyl-8-oxabicyclo[3.2.1]octane-2,4-dione as a white solid (0.142 g).

Workup

  1. customThe reaction mixture is flushed with nitrogen for 15 minutes at ambient temperature
  2. temperatureThe reaction mixture is cooled to room temperature
  3. filtrationfiltered through a plug of diatomaceous earth
  4. customthe two phases are separated
  5. extractionThe aqueous phase is extracted with dichloromethane (2×5 ml)
  6. washwashed with water
  7. dry with materialdried over anhydrous sodium sulfate
  8. filtrationThe mixture is filtered
  9. customthe filtrate is evaporated under reduced pressure
  10. customThe residue is purified by column chromatography on silica gel

Sources & evidence

ORD record
ord-07e6dab7526f46a69f6c7da6047b87ed
Source dataset
uspto-grants-2014_11
Patent number
US08895761B2

Reaction notes

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