Hydrochloric Acid → HCID 14330488, compound

HRID 2292150Notes

Reaction equation

HRID 2292150 reaction equation
C[O:2][C:3]1[C:12]2[S:11][CH2:10][C:9](=O)[CH2:8][C:7]=2[CH:6]=[CH:5][CH:4]=1.[CH3:14][NH:15][CH3:16].[ClH:17]>C1(C)C=CC=CC=1>[ClH:17].[OH:2][C:3]1[C:12]2[S:11][CH2:10][CH:9]([N:15]([CH3:16])[CH3:14])[CH2:8][C:7]=2[CH:6]=[CH:5][CH:4]=1

Participants

5

Procedure

To a solution of 5 g of 8-methoxy-3,4-dihydro-2H-[1]-benzothiopyran-3-one (J. Chem. Soc. 1948, 1610), and 4 g of anhydrous dimethylamine in 50 ml of toluene is stirred with 4 A molecular sieves for 2 hours. The reaction mixture is filtered and the solvent removed in vacuo. This residue is added to a solution of 3.2 g of sodium cyanoborohydride in 10 ml of acetic acid and 50 ml of ethanol. After 30 minutes at room temperature, the reaction mixture is poured onto 3N hydrochloric acid, and washed with ether. After basification of the aqueous layer followed by ether extraction, the organic layer is dried over magnesium sulfate and the solvent removed in vacuo. The residue is added to a solution of lithium diphenylphosphide prepared from 4.9 g diphenylphosphine, 19 ml of 1.3M butyl lithium in hexane and 70 ml of dry tetrahydrofuran, and the mixture is refluxed for 1 hour. The reaction mixture is poured onto 2N hydrochloric acid and washed with ether. After neutralization of the aqueous layer with sodium bicarbonate, the product is extracted with ether and the solvent is removed in vacuo after drying over magnesium sulfate. The residue is dissolved in ethanol; after acidification with 5.4N ethanolic hydrogen chloride and cooling, 8-hydroxy-3,4-dihydro-N,N-dimethyl-2H-[1]-benzothiopyran-3-amine hydrochloride, melting point 172°-173°, is obtained.

Workup

  1. filtrationThe reaction mixture is filtered
  2. customthe solvent removed in vacuo
  3. additionThis residue is added to a solution of 3.2 g of sodium cyanoborohydride in 10 ml of acetic acid and 50 ml of ethanol
  4. additionthe reaction mixture is poured onto 3N hydrochloric acid
  5. washwashed with ether
  6. extractionAfter basification of the aqueous layer followed by ether extraction
  7. dry with materialthe organic layer is dried over magnesium sulfate
  8. customthe solvent removed in vacuo
  9. additionThe residue is added to a solution of lithium diphenylphosphide
  10. customprepared from 4.9 g diphenylphosphine, 19 ml of 1.3M butyl lithium in hexane and 70 ml of dry tetrahydrofuran
  11. temperaturethe mixture is refluxed for 1 hour
  12. washwashed with ether
  13. extractionAfter neutralization of the aqueous layer with sodium bicarbonate, the product is extracted with ether
  14. customthe solvent is removed in vacuo
  15. dry with materialafter drying over magnesium sulfate
  16. dissolutionThe residue is dissolved in ethanol
  17. temperatureafter acidification with 5.4N ethanolic hydrogen chloride and cooling

Sources & evidence

ORD record
ord-e9e00dd93117414f81c2055e42d9ceb6
Source dataset
uspto-grants-1989_01
Patent number
US04801605

Reaction notes

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