Acetic Anhydride → beta-Maltose

HRID 1637434Notes

Reaction equation

HRID 1637434 reaction equation
[CH2:1]([OH:23])[C@H:2]1[O:7][C@H:6]([O:8][C@H:9]2[C@H:14]([OH:15])[C@@H:13]([OH:16])[C@H:12]([OH:17])[O:11][C@@H:10]2[CH2:18][OH:19])[C@H:5]([OH:20])[C@@H:4]([OH:21])[C@@H:3]1[OH:22].O.C(OC(=O)C)(=O)C>N1C=CC=CC=1.CN(C1C=CN=CC=1)C>[CH2:1]([OH:23])[C@H:2]1[O:7][C@H:6]([O:8][C@H:9]2[C@H:14]([OH:15])[C@@H:13]([OH:16])[C@H:12]([OH:17])[O:11][C@@H:10]2[CH2:18][OH:19])[C@H:5]([OH:20])[C@@H:4]([OH:21])[C@@H:3]1[OH:22]

Participants

5

Reactant 2

HCID 7918Acetic AnhydrideHCID 2723821(2R,3S,4S,5R,6R)-2-(hydroxymethyl)-6-[(2R,3S,4R,5R,6R)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxane-3,4,5-triol;hydrate

Product 1

HCID 6255beta-MaltoseYield 198.8%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 1049PyridineSolvent

Procedure

By the method above, but beginning with maltose monchydrate (52), the title compound is obtained as a mixture of diastereomers. To a solution of maltose monohydrate 52 (3.5 g, 9.7 mmol) in 40 mL of pyridine at room temperature is added acetic anhydride (20 mL, 210 mmol) and DMAP (0.10 g, 0.82 mmol). The solution is stirred at room temperature for 5 h and concentrated. The residue is dissolved in 200 mL of CH2Cl2, washed with 1N HCl (4×100 mL), dried over Na2SO4, and concentrated to afford 6.6 g (100%) of peracetylated maltose as the β anomer maltose-47: Rf 0.58 (75% EtOAc/petroleum ether); 1H NMR (CDCl3, 270 MHz) δ 5.74 (d, J=8.2 Hz, 1H, H-1), 5.26-5.41 (m, 3H), 4.94-5.09 (m, 2H), 4.86 (dd, J=10.5, 4.0 Hz, 1H), 4.45 (dd, J=12.4, 2.3 Hz, 1H), 4.19-4.27 (m, 2H), 4.0-4.07 (m, 2H), 3.91-3.96 (m, 1H), 3.80-3.87 (m, 1H), 2.14 (s, 3H), 2.10 (s, 6H), 2.05 (s, 3H), 2.03 (s, 3H), 2.01 (s, 6H), 2.00 (s, 3H).

Workup

  1. concentrationconcentrated
  2. dissolutionThe residue is dissolved in 200 mL of CH2Cl2
  3. washwashed with 1N HCl (4×100 mL)
  4. dry with materialdried over Na2SO4
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-78d8001a59ea462cb5dbf0beb08a02cc
Source dataset
uspto-grants-2000_03
Patent number
US06040433

Reaction notes

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