Pivaloyl chloride → 1-deoxy-1-(phenylthio)-2,3,4,6-tetra-O-pivaloyl-beta-D-galactopyranose

HRID 1637429Notes

Reaction equation

HRID 1637429 reaction equation
[C:1]1([S:7][C@@H:8]2[O:16][C@H:15]([CH2:17][OH:18])[C@H:13]([OH:14])[C@H:11]([OH:12])[C@H:9]2[OH:10])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[C:19](Cl)(=[O:24])[C:20]([CH3:23])([CH3:22])[CH3:21]>N1C=CC=CC=1.CN(C1C=CN=CC=1)C>[C:1]1([S:7][C@@H:8]2[O:16][C@H:15]([CH2:17][O:18][C:19](=[O:24])[C:20]([CH3:23])([CH3:22])[CH3:21])[C@H:13]([O:14][C:19](=[O:24])[C:20]([CH3:23])([CH3:22])[CH3:21])[C@H:11]([O:12][C:19](=[O:24])[C:20]([CH3:23])([CH3:22])[CH3:21])[C@H:9]2[O:10][C:19](=[O:24])[C:20]([CH3:23])([CH3:22])[CH3:21])[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

5

Reactant 2

HCID 62493Pivaloyl chlorideHCID 2802071phenyl thio-beta-D-galactopyranoside

Product 1

HCID 144101731-deoxy-1-(phenylthio)-2,3,4,6-tetra-O-pivaloyl-beta-D-galactopyranoseYield 76.3%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 1049PyridineSolvent

Conditions

Temperature
95 °C

Procedure

To a solution of 1-deoxy-1-(phenylthio)-β-D-galactopyranose (0.38 g, 1.4 mmol) in 25 mL of pyridine, pivaloyl chloride (1.75 mL, 14.0 mmol) and DMAP (0.200 g, 1.40 mmol) are added. The reaction mixture is stirred at 90-100° C. for 8 h. Pyridine is removed under reduced pressure, and the residue is dissolved in 100 mL of CH2Cl2 and washed with dilute HCl (100 mL), H2O (100 mL), dried over Na2SO4, filtered, concentrated and purified by flash chromatography (10% EtOAc/hexane) to give 0.65 g (76%) of 1-deoxy-1-(phenylthio)-2,3,4,6-tetra-O-pivaloyl-β-D-galactopyranose 40: Rf 0.59 (15% EtOAc/hexane); 1H NMR (CDCl3, 270 MHz) δ 7.97 (d, J=8.9 Hz, 2 H, ArH), 7.70 (t, J=7.3 Hz, 1 H, ArH), 7.60 (t, J=7.3 Hz, 2 H, ArH), 5.39 (t, J=9.9 Hz, 1 H, H-2), 5.30 (d, J=3.0 Hz, 1 H, H-4), 5.10 (dd, J=9.9, 3.0 Hz, 1 H, H-3), 4.57 (d, J=9.9 Hz, 1 H, H-1), 4.05-4.20 (m, 2 H, H-6), 3.79 (dd, J=10.6, 5.9 Hz, 1 H, H-5), 1.25-(s, 9 H), 1.18 (s, 9 H), 1.08 (s, 9H), 0.92 (s, 9 H). 13C NMR (CDCl3, 270 MHz) δ 177.7, 177.0, 176.7, 176.3, 134.4, 134.2, 131.0, 128.7, 89.4, 74.9, 71.7, 65.9, 63.9, 60.5, 38.4, 38.7, 38.6, 27.1.

Workup

  1. customPyridine is removed under reduced pressure
  2. dissolutionthe residue is dissolved in 100 mL of CH2Cl2
  3. washwashed with dilute HCl (100 mL), H2O (100 mL)
  4. dry with materialdried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated
  7. custompurified by flash chromatography (10% EtOAc/hexane)

Sources & evidence

ORD record
ord-0f8a17a3f3e44d6584c99caf9abb1d7c
Source dataset
uspto-grants-2000_03
Patent number
US06040433

Reaction notes

Loading…