Oxalic Acid → 1-Methyl-1,3,4,9-tetrahydroindeno[2,1-c]pyran-1-carbaldehyde

HRID 1731141Notes

Reaction equation

HRID 1731141 reaction equation
[CH3:1][C:2]1([CH2:15][OH:16])[C:7]2[CH2:8][C:9]3[CH:10]=[CH:11][CH:12]=[CH:13][C:14]=3[C:6]=2[CH2:5][CH2:4][O:3]1.FC(F)(F)C(O)=O.N1C=CC=CC=1.C(O)(=O)C(O)=O>CS(C)=O.C1C=CC=CC=1.CCOCC.CO.O>[CH3:1][C:2]1([CH:15]=[O:16])[C:7]2[CH2:8][C:9]3[CH:10]=[CH:11][CH:12]=[CH:13][C:14]=3[C:6]=2[CH2:5][CH2:4][O:3]1

Participants

9

Reactant 4

HCID 971Oxalic AcidHCID 1049PyridineHCID 6422Trifluoroacetic acidHCID 21495293HCID 21495293, compound

Product 1

HCID 214953151-Methyl-1,3,4,9-tetrahydroindeno[2,1-c]pyran-1-carbaldehyde

Reagents, catalysts & solvents 4

HCID 887MethanolSolventHCID 962WaterSolventHCID 3283Diethyl EtherSolventHCID 18518713Benzene dimethylsulfoxideSolvent

Procedure

N,N-Dicyclohexylcarbodiimide (2.87 g) is added to a cooled, stirred solution of the primary alcohol, 1-methyl-1,3,4,9-tetrahydroindeno[2,1-c]pyran-1-methanol (1.09 g), described in Example 462, in 10 ml of dimethyl sulfoxide-benzene (2:1) containing trifluoroacetic acid (0.18 ml) and pyridine (0.38 ml). The reaction is stirred at room temperature under nitrogen for 5 hr. The reaction mixture is now diluted with 100 ml of ether, followed by the dropwise addition of a solution of oxalic acid (1.26 g) in 6 ml of methanol. After thirty minutes, water (100 ml) is added and the insoluble material is collected. The organic phase is washed with water (2X), 5% aqueous sodium bicarbonate (2X) and water (2X). After drying (MgSO4) the organic phase is evaporated to yield an oil. The oil is purified by chromatography on silica gel. Elution with 10% ether in benzene affords the title compound as an oil νmaxCHCl3 1720 cm-1.

Workup

  1. waitAfter thirty minutes
  2. customthe insoluble material is collected
  3. washThe organic phase is washed with water (2X), 5% aqueous sodium bicarbonate (2X) and water (2X)
  4. dry with materialAfter drying (MgSO4) the organic phase
  5. customis evaporated
  6. customto yield an oil
  7. customThe oil is purified by chromatography on silica gel
  8. washElution with 10% ether in benzene

Sources & evidence

ORD record
ord-4edbd9b97c1e40d2b6a96414fb0e97b3
Source dataset
uspto-grants-1976_11
Patent number
US03995052

Reaction notes

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