Hydrochloric Acid → 1,2-Dihydro-10-hydroxy-8-(3-methyl-2-octyl)-5-oxo-4H,5H-thiopyrano[3,4-c][1]benzopyran

HRID 1579102Notes

Reaction equation

HRID 1579102 reaction equation
[CH3:1][CH:2]([CH2:13][CH2:14][CH2:15][CH2:16][CH3:17])[CH:3]([C:5]1[CH:6]=[C:7]([OH:12])[CH:8]=[C:9]([CH:11]=1)[OH:10])[CH3:4].O=[C:19]1[CH2:24][CH2:23][S:22][CH2:21][CH:20]1[C:25](OCC)=[O:26].Cl>C(O)C>[OH:10][C:9]1[C:8]2[C:19]3[CH2:24][CH2:23][S:22][CH2:21][C:20]=3[C:25](=[O:26])[O:12][C:7]=2[CH:6]=[C:5]([CH:3]([CH:2]([CH3:1])[CH2:13][CH2:14][CH2:15][CH2:16][CH3:17])[CH3:4])[CH:11]=1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 256936Ethyl 4-oxotetrahydro-2H-thiopyran-3-carboxylateHCID 2581765-(3-Methyloctan-2-yl)benzene-1,3-diol

Product 1

HCID 214339401,2-Dihydro-10-hydroxy-8-(3-methyl-2-octyl)-5-oxo-4H,5H-thiopyrano[3,4-c][1]benzopyran

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of 6.4 g (0.027 mole) of 5-(3-methyl-2-octyl)resorcinol of Example 1 and 5.0 g. (0.0266 mole) of ethyl 4-oxo-2,3,5,6-tetrahydro-4H-thiopyran-3-carboxylate (Bennett and Scorah, J. Chem. Soc., 194 (1922)) in 35 ml. of absolute ethanol was cooled in an ice bath while it was saturated with hydrogen chloride. The resulting deep red solution was tightly stoppered and allowed to stand at room temperature for 120 hours. After one day yellow crystalline material had collected on the bottom of the flask. The reaction mixture was warmed gently on the steam bath for 15 minutes, cooled and poured onto a water-ice mixture. The gum-like material that precipitated was extracted with several portions of chloroform. The chloroform solution was washed with aqueous potassium bicarbonate and with water and dried over sodium sulfate. Evaporation of the solvent left 7.5 g. of a light-colored solid. This material was triturated several times with boiling petroleum ether to remove unreacted keto ester. The residue was recrystallized from an ethyl acetate-petroleum ether mixture to give 6.5 g. (68%) of the compound of formula XXXII, m.p. 153°-155°C. ##SPC30##

Workup

  1. customAfter one day yellow crystalline material had collected on the bottom of the flask
  2. temperatureThe reaction mixture was warmed gently on the steam bath for 15 minutes
  3. temperaturecooled
  4. additionpoured onto a water-ice mixture
  5. customThe gum-like material that precipitated
  6. extractionwas extracted with several portions of chloroform
  7. washThe chloroform solution was washed with aqueous potassium bicarbonate and with water
  8. dry with materialdried over sodium sulfate
  9. customEvaporation of the solvent
  10. waitleft 7.5 g
  11. customThis material was triturated several times with boiling petroleum ether
  12. customto remove unreacted keto ester
  13. customThe residue was recrystallized from an ethyl acetate-petroleum ether mixture
  14. customto give 6.5 g

Sources & evidence

ORD record
ord-3281cbf7029a4f8093adf13381a6fae4
Source dataset
uspto-grants-1976_02
Patent number
US03940421

Reaction notes

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