HCID 12747901, compound → HCID 12747909, compound

HRID 1732323Notes

Reaction equation

HRID 1732323 reaction equation
C[O:2][C:3]([CH:5]1[CH2:9][C:8]2[CH:10]=[C:11]([C:16](=[O:22])[C:17]3[S:21][CH:20]=[CH:19][CH:18]=3)[C:12]([Cl:15])=[C:13]([Cl:14])[C:7]=2[O:6]1)=O.COCCO[AlH2-]OCCOC.[Na+]>O1CCCC1>[Cl:15][C:12]1[C:11]([C:16](=[O:22])[C:17]2[S:21][CH:20]=[CH:19][CH:18]=2)=[CH:10][C:8]2[CH2:9][CH:5]([CH:3]=[O:2])[O:6][C:7]=2[C:13]=1[Cl:14]

Participants

4

Reactant 2

HCID 12747901HCID 12747901, compoundHCID 16684438Red-Al

Product 1

HCID 12747909HCID 12747909, compound

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-70 °C

Procedure

To a stirred solution of (±)methyl-6,7-dichloro-2,3-dihydro-5-(2-thenoyl)benzofuran-2-carboxylate (3.57 g., 0.01 mole) in tetrahydrofuran (50 ml.) at -70° C. is added a solution of "Red-Al" (1.5 g., 0.0107 mole) in tetrahydrofuran (10 ml.) over a ten minute period. The reaction solution is stirred one hour at -70° C. and then quenched with 20% sulfuric acid (10 ml.). The water layer is separated and extracted twice with tetrahydrofuran (10 ml.). The organic layers are combined, washed with brine (two 5 ml. portions), dried over magnesium sulfate and the tetrahydrofuran distilled at reduced pressure. The residue is dissolved in n-butyl chloride (50 ml.) and added to a solution of sodium bisulfite (6 g.) in warm water (10 ml.). The mixture is stirred overnight before the solid bisulfite addition product is added to a saturation sodium bicarbonate solution (25 ml.) and stirred for two hours at room temperature. The mixture is extracted with ether (2×50 ml.). The ether extracts are washed with brine (2×25 ml.), dried over MgSO4 and evaporated in vacuo to give the (±)-6,7-dichloro-2,3-dihydro-5-(2-thenoyl)benzofuran-2-carboxaldehyde which melts at 162°-4° C.

Workup

  1. customquenched with 20% sulfuric acid (10 ml.)
  2. customThe water layer is separated
  3. extractionextracted twice with tetrahydrofuran (10 ml.)
  4. washwashed with brine (two 5 ml. portions)
  5. dry with materialdried over magnesium sulfate
  6. distillationthe tetrahydrofuran distilled at reduced pressure
  7. dissolutionThe residue is dissolved in n-butyl chloride (50 ml.)
  8. additionadded to a solution of sodium bisulfite (6 g.) in warm water (10 ml.)
  9. stirringThe mixture is stirred overnight before the solid bisulfite addition product
  10. additionis added to a saturation sodium bicarbonate solution (25 ml.)
  11. stirringstirred for two hours at room temperature
  12. extractionThe mixture is extracted with ether (2×50 ml.)
  13. washThe ether extracts are washed with brine (2×25 ml.)
  14. dry with materialdried over MgSO4
  15. customevaporated in vacuo

Sources & evidence

ORD record
ord-b68d5c5a276c4b62bcd06b5effc13804
Source dataset
uspto-grants-1980_12
Patent number
US04237144

Reaction notes

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