Hydrochloric Acid → ethyl p-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-7-yl)propenyl]benzoate

HRID 373538Notes

Reaction equation

HRID 373538 reaction equation
[H-].[Na+].[C:3]([C:8]1[CH:22]=[CH:21][C:11]([CH2:12]P(=O)(OCC)OCC)=[CH:10][CH:9]=1)([O:5][CH2:6][CH3:7])=[O:4].[CH3:23][C:24]1([CH3:37])[C:29]2[CH:30]=[CH:31][C:32]([C:34](=O)[CH3:35])=[CH:33][C:28]=2[O:27][CH2:26][CH2:25]1.Cl>CS(C)=O>[CH3:23][C:24]1([CH3:37])[C:29]2[CH:30]=[CH:31][C:32]([C:34]([CH3:35])=[CH:12][C:11]3[CH:10]=[CH:9][C:8]([C:3]([O:5][CH2:6][CH3:7])=[O:4])=[CH:22][CH:21]=3)=[CH:33][C:28]=2[O:27][CH2:26][CH2:25]1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 24758Sodium hydrideHCID 10979490Ethyl 4-((diethoxyphosphoryl)methyl)benzoateHCID 19935426HCID 19935426, compound

Product 1

HCID 53682242ethyl p-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-7-yl)propenyl]benzoateYield 60.3%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent3×

Procedure

0.5 g of a 50% suspension of sodium hydride in mineral oil were suspended in 15 ml of dimethyl sulfoxide and treated under argon with a solution of 3.2 g of diethyl (4-carbethoxybenzyl)phosphonate in 10 ml of dimethyl sulfoxide. The mixture was subsequently heated to 40' C. for 20 minutes, cooled to room temperature, a solution of 0.87 g of 3,4-dihydro-4,4-dimethyl-7-acetyl-2H-1-benzopyran in 5 ml of dimethyl sulfoxide was added dropwise thereto and the mixture was heated to 40° C. for 1 hour. The reaction mixture obtained was poured on to ice/water, acidified with 1N hydrochloric acid and extracted repeatedly with ether. The organic phase was washed with water, dried and evaporated. There was obtained a yellowish oil which, after filtration over a short column (silica gel, eluting agent hexane/ethyl acetate=9:1), crystallized from hexane and yielded 0.9 g of ethyl p-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-7-yl)propenyl]-benzoate, m.p. 49°-50° C.

Workup

  1. temperatureThe mixture was subsequently heated to 40' C
  2. temperaturethe mixture was heated to 40° C. for 1 hour
  3. customThe reaction mixture obtained
  4. extractionextracted repeatedly with ether
  5. washThe organic phase was washed with water
  6. customdried
  7. customevaporated
  8. customThere was obtained a yellowish oil which
  9. filtrationafter filtration
  10. washover a short column (silica gel, eluting agent hexane/ethyl acetate=9:1)
  11. customcrystallized from hexane

Sources & evidence

ORD record
ord-e6a4e8eec8634c1bb4a8232e6f5b468f
Source dataset
uspto-grants-1992_11
Patent number
US05164387

Reaction notes

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