Acetic Anhydride → Keto-L-fructose pentacetate

HRID 345262Notes

Reaction equation

HRID 345262 reaction equation
[C:1]([O:4][C@H:5]([C@H:11]([C@H:16]([CH2:21][O:22][C:23](=[O:25])[CH3:24])[O:17][C:18](=[O:20])[CH3:19])[O:12][C:13](=[O:15])[CH3:14])[C:6](=[O:10])[CH:7]=[N+]=[N-])(=[O:3])[CH3:2].[C:26]([O:29]C(=O)C)(=[O:28])[CH3:27]>[Cl-].[Zn+2].[Cl-].C(O)(=O)C>[C:26]([O:29][CH2:7][C:6]([C@@H:5]([C@H:11]([C@H:16]([CH2:21][O:22][C:23](=[O:25])[CH3:24])[O:17][C:18](=[O:20])[CH3:19])[O:12][C:13](=[O:15])[CH3:14])[O:4][C:1](=[O:3])[CH3:2])=[O:10])(=[O:28])[CH3:27]

Participants

5

Reactant 2

HCID 7918Acetic Anhydride2×HCID 131712179HCID 131712179, compound

Product 1

HCID 10949164Keto-L-fructose pentacetateYield 156.9%

Reagents, catalysts & solvents 2

HCID 3007855ZincchlorideCatalystHCID 176Acetic AcidSolvent

Conditions

Temperature
50 °C

Procedure

A solution of 10 grams of 1-deoxy-1-diazo-keto-L-fructose tetracetate and 0.01 gram of cupric acetate in 300 ml. of anhydrous acetic acid in a 2 liter flask was heated gently and after the initial violent evolution of gas had subsided, was brought just to the boiling point. The solvent was removed by distillation under reduced pressure, the final portion was removed by distillation with ethanol. The resulting syrup was dissolved in 15 ml. of ethanol, filtered and allowed to crystallize overnight in a refrigerator. This yielded 4 grams of crystals, m.p. 65° C. The syrup obtained from mother liquid was dissolved in 50 ml. of acetic anhydride containing 0.5 gram of zinc chloride (fresh fused), allowed to stand overnight at room temperature and heated 90 minutes at 50° C. Excess acetic anhydride was hydrolyzed by pouring into 200 ml. of ice-water and stirred for 2 hours. The acetylated sugar was extracted from the water with 200 ml. of chloroform. The chloroform solution was washed with water, dried over anhydrous sodium sulfate, filtered and evaporated to a syrup. This syrup was crystallized from 10 ml. of ethanol and yielded an additional 3 grams of product.

Workup

  1. customThe solvent was removed by distillation under reduced pressure
  2. customthe final portion was removed by distillation with ethanol
  3. dissolutionThe resulting syrup was dissolved in 15 ml
  4. filtrationof ethanol, filtered
  5. customto crystallize overnight in a refrigerator
  6. customThe syrup obtained from mother liquid
  7. dissolutionwas dissolved in 50 ml
  8. additionby pouring into 200 ml
  9. extractionThe acetylated sugar was extracted from the water with 200 ml
  10. washThe chloroform solution was washed with water
  11. dry with materialdried over anhydrous sodium sulfate
  12. filtrationfiltered
  13. customevaporated to a syrup
  14. customThis syrup was crystallized from 10 ml

Sources & evidence

ORD record
ord-8b36c484c8ac4a1297a2bb1a255a0d5d
Source dataset
uspto-grants-1991_10
Patent number
USRE033719

Reaction notes

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