Hydrochloric Acid → trans-3-acetoxy-6-cyano-3,4-dihydro-2,2-dimethyl-4-(1,2-dihydro-2-oxo-4-hydroxymethyl-1-pyridinyl)-2H-benzo[b]pyran

HRID 487628Notes

Reaction equation

HRID 487628 reaction equation
[C:1]([O:4][C@@H:5]1[C:10]([CH3:12])([CH3:11])[O:9][C:8]2[CH:13]=[CH:14][C:15]([C:17]#[N:18])=[CH:16][C:7]=2[C@H:6]1[N:19]1[CH:24]=[CH:23][C:22]([CH2:25][O:26][Si](C(C)(C)C)(C)C)=[CH:21][C:20]1=[O:34])(=[O:3])[CH3:2].Cl>CO.O1CCOCC1>[C:1]([O:4][C@@H:5]1[C:10]([CH3:12])([CH3:11])[O:9][C:8]2[CH:13]=[CH:14][C:15]([C:17]#[N:18])=[CH:16][C:7]=2[C@H:6]1[N:19]1[CH:24]=[CH:23][C:22]([CH2:25][OH:26])=[CH:21][C:20]1=[O:34])(=[O:3])[CH3:2]

Participants

5

Reactant 2

HCID 313Hydrochloric AcidHCID 131718355trans-3-acetoxy-6-cyano-3,4-dihydro-2,2-dimethyl-4-(1,2-dihydro-2-oxo-4-t-butyldimethylsilyloxymethyl-1-pyridinyl)-2H-benzo[b]pyran

Product 1

HCID 67821378trans-3-acetoxy-6-cyano-3,4-dihydro-2,2-dimethyl-4-(1,2-dihydro-2-oxo-4-hydroxymethyl-1-pyridinyl)-2H-benzo[b]pyranYield 95.8%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 312751,4-DioxaneSolvent

Procedure

In 15.0 ml of methanol, is dissolved 1.45 g of trans-3-acetoxy-6-cyano-3,4-dihydro-2,2-dimethyl-4-(1,2-dihydro-2-oxo-4-t-butyldimethylsilyloxy-1-pyridinyl)-2H-benzo[b]pyran obtained in Example 4. Then, 3.00 ml of 4N hydrochloric acid in dioxane is added thereto at 0° C. and reacted at room temperature for 2 hours. The reaction mixture is concentrated under reduced pressure, the residue is mixed with water and ethyl acetate, and the product is extracted by ethyl acetate. The organic layer is washed with saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. Then, the inorganic matter is filtered off and the filtrate is concentrated under reduced pressure. The residue is purified by silica gel column chromatography using ethyl acetate as a developing solvent to obtain 1.06 g of trans-3-acetoxy-6-cyano-3,4-dihydro-2,2-dimethyl-4-(1,2-dihydro-2-oxo-4-hydroxymethyl-1-pyridinyl)-2H-benzo[b]pyran.

Workup

  1. customat 0° C. and reacted at room temperature for 2 hours
  2. concentrationThe reaction mixture is concentrated under reduced pressure
  3. additionthe residue is mixed with water and ethyl acetate
  4. extractionthe product is extracted by ethyl acetate
  5. washThe organic layer is washed with saturated aqueous solution of sodium chloride
  6. dry with materialdried over anhydrous sodium sulfate
  7. filtrationThen, the inorganic matter is filtered off
  8. concentrationthe filtrate is concentrated under reduced pressure
  9. customThe residue is purified by silica gel column chromatography

Sources & evidence

ORD record
ord-a89a39ed35484a80bb1e92a62f3e07b5
Source dataset
uspto-grants-1994_03
Patent number
US05296492

Reaction notes

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