1,2-Dichloroethane → (2R,3S,4R,5R,6R)-2-(Acetoxymethyl)-6-(benzyloxy)-5-(1,3-dioxoisoindolin-2-yl)tetrahydro-2H-pyran-3,4-diyl diacetate

HRID 1707406Notes

Reaction equation

HRID 1707406 reaction equation
[C:1]([O:4][C@@H:5]1[O:18][C@H:17]([CH2:19][O:20][C:21](=[O:23])[CH3:22])[C@@H:12]([O:13][C:14](=[O:16])[CH3:15])[C@H:7]([O:8][C:9](=[O:11])[CH3:10])[C@H:6]1[N:24]1[C:28](=[O:29])[C:27]2=[CH:30][CH:31]=[CH:32][CH:33]=[C:26]2[C:25]1=[O:34])(=O)[CH3:2].ClCCCl.C(O)[C:40]1[CH:45]=[CH:44]C=[CH:42][CH:41]=1.FC(F)(F)S(O[Si](C)(C)C)(=O)=O>CCCCCC.C(OCC)(=O)C>[C:9]([O:8][C@H:7]1[C@H:12]([O:13][C:14](=[O:16])[CH3:15])[C@@H:17]([CH2:19][O:20][C:21](=[O:23])[CH3:22])[O:18][C@@H:5]([O:4][CH2:1][C:2]2[CH:44]=[CH:45][CH:40]=[CH:41][CH:42]=2)[C@@H:6]1[N:24]1[C:28](=[O:29])[C:27]2=[CH:30][CH:31]=[CH:32][CH:33]=[C:26]2[C:25]1=[O:34])(=[O:11])[CH3:10]

Participants

7

Reactant 4

HCID 111,2-DichloroethaneHCID 244Benzyl AlcoholHCID 65367Trimethylsilyl triflateHCID 2728904beta-D-Glucopyranose, 2-deoxy-2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)-, 1,3,4,6-tetraacetate

Product 1

HCID 11237799(2R,3S,4R,5R,6R)-2-(Acetoxymethyl)-6-(benzyloxy)-5-(1,3-dioxoisoindolin-2-yl)tetrahydro-2H-pyran-3,4-diyl diacetateYield 85%

Reagents, catalysts & solvents 2

HCID 8058HexaneSolventHCID 8857Ethyl AcetateSolvent

Procedure

Under anhydrous conditions, 1,3,4,6-tetra-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranose (5) (47.7 g, 100 mM), molecular sieves (4 Å) powder (20 g) and 250 ml of 1,2-dichloroethane and benzyl alcohol (12.5 ml, 120 mM) were placed in a dry 1 liter round bottom flask equipped with magnetic stirring bar, septum inlet and bent tube adapter. During a 5 minute period, trimethylsilyl trifluoromethane sulfonate (19.3 ml, 100 mM) was then added to the stirred mixture. The contents were stirred at room temperature for 16 hours. The reaction was found to be complete as evidenced by the products present on thin layer chromtography (TLC, 2:3 ethyl acetate:hexane). The reaction mixture was cooled in an ice-bath, quenched with saturated sodium bicarbonate and extracted with dichloromethane in the manner well known to those skilled in the art. The combined extract was washed with water, brine and dried over anhydrous magnesium sulfate. The residue after removal of solvent was purified by "flash chromatography" (silica gel, 500 g, solvent 1:3 ethyl acetate:hexane) to provide 40.6 g (85% yield) of benzyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-β-D-glucopyranoside (6).

Workup

  1. customequipped with magnetic stirring bar, septum inlet
  2. temperatureThe reaction mixture was cooled in an ice-bath
  3. customquenched with saturated sodium bicarbonate
  4. extractionextracted with dichloromethane in the manner
  5. extractionThe combined extract
  6. washwas washed with water, brine
  7. dry with materialdried over anhydrous magnesium sulfate
  8. customThe residue after removal of solvent
  9. customwas purified by "flash chromatography" (silica gel, 500 g, solvent 1:3 ethyl acetate:hexane)

Sources & evidence

ORD record
ord-270369d0387a498e8d8679c6013f43ce
Source dataset
uspto-grants-1994_10
Patent number
US05352811

Reaction notes

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