Hydrochloric Acid → [10-Methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-ylidene]-acetic acid ethyl ester

HRID 649525Notes

Reaction equation

HRID 649525 reaction equation
[H-].[Na+].[CH3:3][O:4][C:5]1[C:11]2[S:12][CH:13]=[CH:14][C:10]=2[C:9](=O)[C:8]2[CH:16]=[CH:17][CH:18]=[CH:19][C:7]=2[CH:6]=1.O.Cl.[CH2:22]([O:24][C:25](=[O:27])[CH3:26])[CH3:23]>CS(C)=O.CN(C)C=O>[CH2:22]([O:24][C:25](=[O:27])[CH:26]=[C:9]1[C:10]2[CH:14]=[CH:13][S:12][C:11]=2[C:5]([O:4][CH3:3])=[CH:6][C:7]2[CH:19]=[CH:18][CH:17]=[CH:16][C:8]1=2)[CH3:23]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 962WaterHCID 8857Ethyl AcetateHCID 24758Sodium hydrideHCID 282516210-Methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-one

Product 1

HCID 54193692[10-Methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-ylidene]-acetic acid ethyl ester

Reagents, catalysts & solvents 2

HCID 679Dimethyl SulfoxideSolventHCID 6228DimethylformamideSolvent

Procedure

21.6 g pre-dried NaH are suspended in 0.9 l dimethylsulfoxide and 200 g ethoxycarbonylmethylen-diethylphosphonate [(C2H5O)2POCH2COOC2H5 ] are added drop-wise over ca. 1 hour, the temperature being maintained at ca. 25°-30° C. by light cooling. The obtained mixture is then stirred for 30 minutes at room temperature and 121 g 10-methoxy-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-one dissolved with warming in 0.9 l dimethylformamide are then added in a single portion. The obtained reaction mixture is stirred for ca. 17 hours at ca. 95° C. under argon, and then stirred into a mixture of 7 l H2O/3 kg ice and 50 ml conc. HCl covered with a layer of 2 l ethylacetate. The organic phase is separated off and the aqueous phase extracted 3× with 2 l and 3× with 1 l ethyl acetate. The combined organic phases are washed 3× with 2 l H2O and 3× with 2 l saline, dried with MgSO4, filtered under suction and concentrated on a rotary evaporator to yield the title compound as a (Z,E)-isomer mixture: m.p.=91°-93° C.

Workup

  1. temperaturethe temperature being maintained at ca. 25°-30° C. by light
  2. temperaturecooling
  3. additionare then added in a single portion
  4. customThe obtained reaction mixture
  5. stirringis stirred for ca. 17 hours at ca. 95° C. under argon
  6. customThe organic phase is separated off
  7. extractionthe aqueous phase extracted 3× with 2 l and 3× with 1 l ethyl acetate
  8. washThe combined organic phases are washed 3× with 2 l H2O and 3× with 2 l saline
  9. dry with materialdried with MgSO4
  10. filtrationfiltered under suction
  11. concentrationconcentrated on a rotary evaporator

Sources & evidence

ORD record
ord-b044336ec43b4de9b81a1a16d7b85375
Source dataset
uspto-grants-1988_04
Patent number
US04740518

Reaction notes

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