Dichloromethane → HCID 86587396, compound

Participants

Reaction Steps

1.28 g (1 eq.) of benzyl 2-O-acetyl-3-O-allyl-4,6-di-O-benzyl-β-D-gluco-pyranosyl-(1→3)-2-O-acetyl-4,6-di-O-benzyl-β-D-glucopyranoside (M=915) and 1.18 g of Dabco are dissolved in 50 ml of an ethanol/toluene/water (8/3/1; v/v/v) mixture and then 390 mg (0.3 eq.) of Wilkinson's catalyst are added thereto. The reaction medium is heated under reflux for 1 hour 30 minutes and then put to dryness. The mixture is then taken up with dichloromethane and extracted with water, with iced 1/2N HCl, with 5% NaHCO3 and then with water, dried and concentrated. The residue is then redissolved in 30 ml of an acetone/10% aq. HCl (19/1; v/v) mixture which is refluxed for 8 min. After rapid cooling to R.T., the solution is neutralised with a few drops of 5% NaHCO3 and concentrated. The whole is diluted again with dichloromethane and is extracted with water. The product is finally purified over silica gel [flash; eluent: toluene/ethyl acetate (85/15; v/v)] which thus enables isolating 600 mg of benzyl 2-O-acetyl-4,6-di-O-benzyl-β-D-glucopyranosyl-(1→3)-2-O-acetyl-4,6-di-O-benzyl-β-D-glucopyranoside (M=875).

Provenance & Evidence