Trifluoroacetic acid → HCID 13317003, compound

HRID 325537Notes

Reaction equation

HRID 325537 reaction equation
[CH2:1]([O:8][C@@H:9]1[C@H:16]([O:17][S:18]([C:21]2[CH:27]=[CH:26][C:24]([CH3:25])=[CH:23][CH:22]=2)(=[O:20])=[O:19])[C@@H:15]([CH2:28][O:29]C(C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[O:14][C@H:11]([O:12][CH3:13])[CH2:10]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.FC(F)(F)C(O)=O>C(Cl)Cl>[CH2:1]([O:8][C@@H:9]1[C@H:16]([O:17][S:18]([C:21]2[CH:22]=[CH:23][C:24]([CH3:25])=[CH:26][CH:27]=2)(=[O:20])=[O:19])[C@@H:15]([CH2:28][OH:29])[O:14][C@H:11]([O:12][CH3:13])[CH2:10]1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

4

Reactant 2

HCID 6422Trifluoroacetic acidHCID 14010511HCID 14010511, compound

Product 1

HCID 13317003HCID 13317003, compoundYield 83.3%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Methyl 3-O-benzyl-4-O-tosyl-6-O-trityl-2-deoxy-α-D-ribo-hexopyranoside (15.3 g; 23.01 mmoles) was dissolved in methylene chloride (200 ml). Aqueous trifluoroacetic acid (70% TFA in water, 9.6 ml) was added with vigorous stirring. The vigorous stirring was continued for five minutes (bright yellow color appears), then the reaction was quenched by the addition of saturated aqueous sodium carbonate solution (40 ml) with vigorous stirring (note: the reaction becomes colorless). The methylene chloride layer was separated and the aqueous layer extracted with methylene chloride. The combined methylene chloride extracts were dried (MgSO4), filtered and the solvent was evaporated in vacuo to give crude product. This product was chromatographed on 650 g of silica gel eluting with 3 L of methylene chloride to remove triphenyl carbinol from the column followed by elution with 10% (by volume) acetone in methylene chloride. When a faintly visible opaque band of product neared the bottom of the column the fractions containing the product were collected and the solvent was evaporated in vacuo to leave 8.1 g of methyl 3 -O-benzyl-4-O-tosyl-2-deoxy-α-D-ribo-hexopyranoside, m.p. 100°-101° C., [α]D25 =115.07 (c, 0.48, CHCl3)

Workup

  1. custom(bright yellow color appears), then the reaction was quenched by the addition of saturated aqueous sodium carbonate solution (40 ml)
  2. stirringwith vigorous stirring (note
  3. customThe methylene chloride layer was separated
  4. extractionthe aqueous layer extracted with methylene chloride
  5. dry with materialThe combined methylene chloride extracts were dried (MgSO4)
  6. filtrationfiltered
  7. customthe solvent was evaporated in vacuo
  8. customto give crude product
  9. customThis product was chromatographed on 650 g of silica gel eluting with 3 L of methylene chloride
  10. customto remove triphenyl carbinol from the column
  11. washfollowed by elution with 10% (by volume) acetone in methylene chloride
  12. additioncontaining the product
  13. customwere collected
  14. customthe solvent was evaporated in vacuo

Sources & evidence

ORD record
ord-b8ef9a6d69a543fcafbdb0171cf1588d
Source dataset
uspto-grants-1984_04
Patent number
US04440927

Reaction notes

Loading…