p-Toluenesulfonic acid → 2,3:5,6-Di-O-isopropylidene-L-gulonolactone

HRID 329967

Reaction equation

HRID 329967 reaction equation
[CH2:1]([OH:12])[C@H:2]([OH:11])[C@H:3]1[O:8][C:6](=[O:7])[C@@H:5]([OH:9])[C@H:4]1[OH:10].CO[C:15](OC)([CH3:17])[CH3:16].[C:20]1(C)[CH:25]=CC(S(O)(=O)=O)=C[CH:21]=1.C(=O)(O)[O-].[Na+]>C(Cl)(Cl)Cl.CC(C)=O.C(OCC)(=O)C>[CH3:16][C:15]1([CH3:17])[O:11][CH:2]([CH:3]2[O:8][C:6](=[O:7])[CH:5]3[O:9][C:20]([CH3:25])([CH3:21])[O:10][CH:4]23)[CH2:1][O:12]1

Participants

8

Reactant 4

HCID 6101p-Toluenesulfonic acidHCID 64952,2-DimethoxypropaneHCID 439373L-Gulonic acid, gamma-lactone2×HCID 516892Sodium Bicarbonate

Product 1

HCID 5682882,3:5,6-Di-O-isopropylidene-L-gulonolactoneYield 85%

Reagents, catalysts & solvents 3

HCID 180AcetoneSolventHCID 6212ChloroformSolventHCID 8857Ethyl AcetateSolvent

Procedure

m.p. 155° C. (from ethyl acetate) [α]D20 -76.6° (c, 1.99 in CHCl3), was prepared from L-gulonolactone in 85% yield as previously described by Fleet in copending application Ser. No. 249,153, filed Sept. 26, 1988. According to this method, the title compound is synthesized by treatment of L-gulonolactone with acetone and 2,2-dimethoxypropane and a catalytic amount of p-toluenesulfonic acid under dry nitrogen for 36 hours (h) followed by stirring with an excess of sodium bicarbonate, removing the solvent under reduced pressure, dissolving the residue in dichloromethane, washing with water, drying the organic extracts (MgSO4), removing the solvent under reduced pressure and recrystallizing from ethyl acetate to give a white crystalline solid.

Workup

  1. customremoving the solvent under reduced pressure
  2. dissolutiondissolving the residue in dichloromethane
  3. washwashing with water
  4. dry with materialdrying the organic extracts (MgSO4)
  5. customremoving the solvent under reduced pressure
  6. customrecrystallizing from ethyl acetate
  7. customto give a white crystalline solid

Sources & evidence

ORD record
ord-bdbb1b62a75e4e439207e4069eb2d41a
Source dataset
uspto-grants-1990_01
Patent number
US04894388

Linked notes

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