Sodium hydride → (1S,3R,4R,7S)-7-Benzyloxy-1-benzyloxymethyl-3-methoxy-2,5-dioxabicyclo[2.2.1]heptane

HRID 434287Notes

Reaction equation

HRID 434287 reaction equation
[CH2:1]([O:8][C@@H:9]1[C@@:15]([CH2:25][O:26]S(C)(=O)=O)([CH2:16][O:17][CH2:18][C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)[O:14][C@H:11]([O:12][CH3:13])[C@@H:10]1O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Na+]>CN(C=O)C>[CH2:1]([O:8][C@H:9]1[C@H:10]2[O:26][CH2:25][C@:15]1([CH2:16][O:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)[O:14][C@H:11]2[O:12][CH3:13])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 24758Sodium hydrideHCID 20610801Methyl 3,5-di-O-benzyl-4-C-methanesulfonyloxymethyl-alpha-D-ribofuranoside

Product 1

HCID 56975532(1S,3R,4R,7S)-7-Benzyloxy-1-benzyloxymethyl-3-methoxy-2,5-dioxabicyclo[2.2.1]heptane

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A solution of 201 (3.32 g, 7.34 mmol) in anhydrous DMF (25 mL) was stirred at 0° C. and a 60% oil dispersion of sodium hydride (700 mg, 16.9 mmol) was added. The mixture was stirred at room temperature for 90 min, quenched with water (300 mL) and extracted with diethyl ether (2×300 mL). The combined extract was washed with water (200 mL) and dried (MgSO4). The solvent was removed under reduced pressure and the residue was purified by chromatography over silica gel with dichloromethane as eluent to give the two products 202 and 203 as clear oils (1.571 g, 60% and 0.777 g, 30% respectively). (1S,3R,4R,7S)-7-Benzyloxy-1-benzyloxymethyl-3-methoxy-2,5-dioxabi-cyclo[2.2.1]heptane (202). 1H NMR (CDCl3): δ 7.36-7.26 (10H, m, Bn), 4.81 (1H, s, H-1), 4.65 (1H, d, J 11.9 Hz, Bn), 4.61 (2H, s, Bn), 4.56 (1H, d, J 11.9 Hz, Bn), 4.11 (1H, s, H-2), 4.09 (1H, s, H-3), 4.01 (1H, d, J 7.5 Hz, H-5′), 3.80-3.77 (3H, m, H-5′, H-5), 3.39 (3H, s, OCH3); 13C NMR (CDCl3): δ 138.05, 137.36, 128.47, 128.44, 127.88, 127.73, 127.63 (Bn), 104.97 (C-1), 85.13 (C-4), 79.16 (C-3), 77.18 (C-2), 73.64 (Bn), 72.26, 72.10 (Bn, C-5′), 66.50 (C-5), 55.34 (OCH3); MS FAB: 379 (M+Na, 28%). Found: C, 70.55; H, 6.97; C21H24O5 requires C, 70.77; H, 6.79%. (1S,3R,4R,7S)-7-Benzyloxy-1-benzyloxymethyl-3-methoxy-2,5-dioxabicyclo-[2.2.1]heptane (203). 1H NMR (CDCl3): δ 7.36-7.26 (10H, m, Bn), 5.00 (1H, s, H-1), 4.67-4.54 (4H, m, Bn), 4.18 (1H, s, H-2), 3.99 (1H, s, H-3), 3.99-3.90 (2H, m, H-5′), 3.75-3.68 (2H, m, H-5), 3.49 (3 H, s, OCH3); 13C NMR (CDCl3): δ 137.83, 137.53, 128.51, 128.48, 127.96, 127.82, 127.71, 127.62 (Bn), 104.05 (C-1), 88.44 (C-4), 79.54 (C-3), 77.16 (C-2), 73.68 (Bn), 72.61 (C-5′), 72.24 (Bn), 65.73 (C-5), 56.20 (OCH3); MS FAB: 379 (M+Na, 100%).

Workup

  1. customquenched with water (300 mL)
  2. extractionextracted with diethyl ether (2×300 mL)
  3. extractionThe combined extract
  4. washwas washed with water (200 mL)
  5. dry with materialdried (MgSO4)
  6. customThe solvent was removed under reduced pressure
  7. customthe residue was purified by chromatography over silica gel with dichloromethane as eluent

Sources & evidence

ORD record
ord-70dea1381018432fbfdd74de9dc9fd7f
Source dataset
uspto-grants-2003_12
Patent number
US06670461B1

Reaction notes

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