Benzyl Bromide → 2,5-anhydro-3,4,6-tris-O-(phenylmethyl)-D-mannose

HRID 2166487Notes

Reaction equation

HRID 2166487 reaction equation
[O:1]=[CH:2][C@H:3]1[O:9][C@H:8]([CH2:10][OH:11])[C@@H:6]([OH:7])[C@@H:4]1[OH:5].[H-].[Na+].[CH2:14](Br)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1>CN(C)C=O>[C:15]1([CH2:14][O:5][C@H:4]2[C@H:6]([O:7][CH2:14][C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[C@@H:8]([CH2:10][O:11][CH2:14][C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[O:9][C@@H:3]2[CH:2]=[O:1])[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 111163532,5-Anhydromannose

Product 1

HCID 108364862,5-anhydro-3,4,6-tris-O-(phenylmethyl)-D-mannose

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

According to Flowchart C, 2,5-anhydro-D-mannose 24, is protected as the dimethyl acetal 25 which is reacted with sodium hydride in dimethylformamide, followed by benzyl bromide giving 2,5-anhydro-3,4,6-tris-O-(phenylmethyl)-D-mannose, dimethyl acetal 26. Compound 26 is treated with tetrafluoroboric acid in acetonitrile giving 2,5-anhydro-3,4,6-tris-O-(phenylmethyl)-D-mannose 27 which is reacted with diphenyl triphenylphosphoranylidenemethylphosphonate in toluene at reflux, giving 3,6-anhydro-1,2-dideoxy-1-(diphenoxyphosphinyl)-4,5,7-tris-O-(phenylmethyl)-D-manno-hept-1-enitol 28. Compound 28 is hydrogenated over palladium on carbon in methanol and acetic acid, giving 3,6-anhydro-1,2-dideoxy-1-(diphenoxyphosphinyl)-D-manno-heptitol 29, which is reacted with diphenyl chlorophosphate in pyridine, giving 3,6-anhydro-1,2-dideoxy-1-(diphenoxyphosphinyl)-D-manno-heptitol, 7-(diphenyl phosphate) 30, which is then hydrogenated with platinum oxide, giving the product 3,6-anhydro-1,2-dideoxy-1-phosphono-D-manno-heptitol, 7-(dihydrogen phosphate) 31. ##STR11##

Sources & evidence

ORD record
ord-76ff7cf881ca4068854ad013e15e3537
Source dataset
uspto-grants-1990_07
Patent number
US04945158

Reaction notes

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