5-Chlorocarbonylphthalide → 1-oxo-1,3-dihydroisobenzofuran-5-carbaldehyde

HRID 2180319Notes

Reaction equation

HRID 2180319 reaction equation
Cl[C:2]([C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][CH:13]=1)[C:9](=[O:10])[O:8][CH2:7]2)=[O:3].N1C2C(=CC=CC=2)C=CC=1.[S]>[Pd].[O-]S([O-])(=O)=O.[Ba+2].C1(C)C=CC=CC=1>[CH:2]([C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][CH:13]=1)[C:9](=[O:10])[O:8][CH2:7]2)=[O:3]

Participants

5

Reactant 2

HCID 98155555-ChlorocarbonylphthalideHCID 178527711HCID 178527711, compound

Product 1

HCID 98774631-oxo-1,3-dihydroisobenzofuran-5-carbaldehydeYield 72%

Reagents, catalysts & solvents 2

HCID 16218511Pd barium sulfateCatalystHCID 1140TolueneSolvent

Procedure

In a hydrogenator a mixture of 7 g (0.036 mole) of 5-chlorocarbonylphthalide, 50 ml of toluene, 0.1 ml of the quinoline/sulfur mixture and 0.7 g of previously reduced 5% Pd/BaSO4 is charged. The mixture is hydrogenated at 80° C. under 3.5 bar for 7 hours. At this point the reaction no longer proceeds because of the co-precipitation of the formed product Thus, it is stopped and the mixture is filtered in the warm in order to put the product. into solution again. A second amount of 0.7 g of 5% Pd/BaSO4 is added to the filtrate and the hydrogenation starts again under the above described conditions. After 15 minutes, no more absorption of hydrogen is observed. Hydrogenation is stopped and the catalyst is filtered off in the warm. After cooling, the solution is concentrated under vacuum to a residue which is taken up with ethyl acetate. The organic phase is washed with a 5% aqueous solution of NaHCO3, concentrated to a little volume and the separated product is filter. There is obtained 4.2 g of 5-formylphthalide with a purity (HPLC)=42% (yield 30%).

Workup

  1. additionis charged
  2. customAt this point the reaction
  3. filtrationthe mixture is filtered in the
  4. temperaturewarm in order
  5. additionA second amount of 0.7 g of 5% Pd/BaSO4 is added to the filtrate
  6. waitAfter 15 minutes
  7. customno more absorption of hydrogen
  8. filtrationthe catalyst is filtered off in the warm
  9. temperatureAfter cooling
  10. concentrationthe solution is concentrated under vacuum to a residue which
  11. washThe organic phase is washed with a 5% aqueous solution of NaHCO3
  12. concentrationconcentrated to a little volume
  13. filtrationthe separated product is filter

Sources & evidence

ORD record
ord-9bd252d4824e4947bbe8e4167fd0b111
Source dataset
uspto-grants-2005_05
Patent number
US06888010B2

Reaction notes

Loading…