3,4-dihydro-2H-pyran → HCID 23044419, compound

HRID 2165236Notes

Reaction equation

HRID 2165236 reaction equation
[CH2:1]([O:8][C:9]([NH:11][CH:12]([CH:17]([OH:22])[C:18]([F:21])([F:20])[F:19])[C:13]([O:15]C)=[O:14])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[O:23]1[CH:28]=[CH:27][CH2:26][CH2:25][CH2:24]1.C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1>C(Cl)Cl>[CH2:1]([O:8][C:9]([NH:11][CH:12]([CH:17]([O:22][CH:24]1[CH2:25][CH2:26][CH2:27][CH2:28][O:23]1)[C:18]([F:21])([F:20])[F:19])[C:13]([OH:15])=[O:14])=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 80803,4-dihydro-2H-pyranHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)HCID 23044427HCID 23044427, compound

Product 1

HCID 23044419HCID 23044419, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of methyl 2-(N-benzyloxycarbonylamino)3-hydroxy-4,4,4-trifluorobutyrate (3.3 g) in methylene chloride (33 ml) was added dihydropyran (1.1 ml) and pyridinium p-toluenesulfonate (251 mg) at room temperature. After stirring for 2 hours at room temperature, the solvent was distilled off and the residue was diluted with ethyl acetate, washed successively with aqueous sodium hydrogen carbonate and brine. After drying over sodium sulfate, the ethyl acetate was evaporated and the residue was diluted with methanol (20 ml). To the methanol solution was added 1N sodium hydroxide (10 ml) and the mixture was stirred for 2 hours at room temperature. The solvent distilled off and the residue was washed with ethyl acetate. The aqueous layer was acidified with citric acid to pH 4 and extracted with ethyl acetate (2 times). The combined ethyl acetate extracts were washed with brine, dried over sodium sulfate, filtered and concentrated. The residue was crystallized with a mixture of diisopropylether and hexane to give 2-(N-benzyloxycarbonylamino)-3-(2-tetrahydropyranyloxy)- 4,4,4,-trifluorobutyric acid (1 g).

Workup

  1. distillationthe solvent was distilled off
  2. additionthe residue was diluted with ethyl acetate
  3. washwashed successively with aqueous sodium hydrogen carbonate and brine
  4. dry with materialAfter drying over sodium sulfate
  5. customthe ethyl acetate was evaporated
  6. additionthe residue was diluted with methanol (20 ml)
  7. additionTo the methanol solution was added 1N sodium hydroxide (10 ml)
  8. stirringthe mixture was stirred for 2 hours at room temperature
  9. distillationThe solvent distilled off
  10. washthe residue was washed with ethyl acetate
  11. extractionextracted with ethyl acetate (2 times)
  12. washThe combined ethyl acetate extracts were washed with brine
  13. dry with materialdried over sodium sulfate
  14. filtrationfiltered
  15. concentrationconcentrated
  16. customThe residue was crystallized with a mixture of diisopropylether and hexane

Sources & evidence

ORD record
ord-9054ea915ed7404cb1ab216b04e8bd86
Source dataset
uspto-grants-1990_07
Patent number
US04939241

Reaction notes

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