Benzyl Bromide → Phenyl 3-O-benzyl-1-thio-beta-D-galactopyranoside

HRID 1910652Notes

Reaction equation

HRID 1910652 reaction equation
[S:1]([C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1)[C@@H:2]1[O:10][C@H:9]([CH2:11][OH:12])[C@H:7]([OH:8])[C@H:5]([OH:6])[C@H:3]1[OH:4].C([Sn](=O)CCCC)CCC.[CH:29]1[CH:34]=[CH:33][C:32]([CH2:35]Br)=[CH:31][CH:30]=1>CO.[N+](CCCC)(CCCC)(CCCC)CCCC.[Br-]>[CH2:35]([O:6][C@H:5]1[C@@H:7]([OH:8])[C@@H:9]([CH2:11][OH:12])[O:10][C@@H:2]([S:1][C:13]2[CH:14]=[CH:15][CH:16]=[CH:17][CH:18]=2)[C@@H:3]1[OH:4])[C:32]1[CH:33]=[CH:34][CH:29]=[CH:30][CH:31]=1

Participants

6

Reactant 3

HCID 7498Benzyl BromideHCID 61221Dibutyltin oxideHCID 2802071phenyl thio-beta-D-galactopyranoside

Product 1

HCID 86653955Phenyl 3-O-benzyl-1-thio-beta-D-galactopyranosideYield 68%

Reagents, catalysts & solvents 2

HCID 74236Tetrabutylammonium BromideCatalystHCID 887MethanolSolvent

Procedure

A solution of phenyl 1-thio-β-D-galactopyranoside (2.1) (3.00 g, 11.0 mmol) and dibutyltin oxide (3.00 g, 12.1 mmol) in dry methanol (80 ml) was refluxed for 2 hours to produce a clear mixture. The solvent was then evaporated under reduced pressure. The resultant residue was dissolved in dry benzene (80 mL) followed by the addition of Bu4NBr (3.90 g, 12.11 mmol) and BnBr (1.3 ml, 12.1 mmol). The mixture was refluxed overnight. After cooling to room temperature, the mixture was concentrated and the residue was purified by silica gel chromatography (50% EtOAc/petroleum ether) to afford the title compound (2.71 g, 7.48 mmol, 67%). 1H NMR (400 MHz, CDCl3): δ 7.60-7.20 (m, 10H, PhH), 4.77, 4.68 (ABq, J=11.7 Hz, 1H each, OCH2Ph), 4.59 (d, J=9.5 Hz, 1H, H-1), 4.08 (d, J=2.6 Hz, 1H, H-4), 3.76 (dd, J=9.5, 9.5 Hz, 1H, H-2), 3.75 (dd, J=11.4, 5.8 Hz, 1H, H-6), 3.70 (dd, J=11.4, 5.8 Hz, 1H, H-6), 3.50 (dd, J=5.8, 5.8 Hz, 1H, H-5), 3.41 (dd, J=9.5, 2.6 Hz, 1H, H-3); 13C NMR (100 MHz, CDCl3): δ 131.0, 128.6, 128.1, 127.8, 127.4, 126.8, 89.1, 82.5, 79.2, 71.5, 69.0, 66.2, 61.4; HRMS calcd for C19H26O5SN [M+NH4]+: 380.1532. found 380.1527.

Workup

  1. customto produce a clear mixture
  2. customThe solvent was then evaporated under reduced pressure
  3. dissolutionThe resultant residue was dissolved in dry benzene (80 mL)
  4. temperatureThe mixture was refluxed overnight
  5. concentrationthe mixture was concentrated
  6. customthe residue was purified by silica gel chromatography (50% EtOAc/petroleum ether)

Sources & evidence

ORD record
ord-c8fd9f9f100f4ea9948140cd60f7baec
Source dataset
uspto-grants-2013_12
Patent number
US08604004B2

Reaction notes

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