Lithium Bromide → (+)-1-Hexadecylthio-2-methoxy-3-bromopropane

HRID 977286Notes

Reaction equation

HRID 977286 reaction equation
[CH2:1]([S:17][CH2:18][CH:19]([CH2:22]OS(C)(=O)=O)[O:20][CH3:21])[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH3:16].[Br-:28].[Li+]>CC(C)=O>[CH2:1]([S:17][CH2:18][CH:19]([O:20][CH3:21])[CH2:22][Br:28])[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH3:16]

Participants

4

Reactant 2

HCID 82050Lithium BromideHCID 14522778(+/-)-1-S-hexadecyl-2-O-methyl-3-O-mesylthioglycerol

Product 1

HCID 14522781(+)-1-Hexadecylthio-2-methoxy-3-bromopropaneYield 87.2%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

Into a flask equipped with a magnetic stir bar, drying tube, and a reflux condenser, a solution of 3.0 grams (0.007 mole) (±)-1-S-hexadecyl-2-O-methyl-3-O-mesylthioglycerol and 2.5 grams (0.029 mole) of lithium bromide in 150 milliliters of acetone was refluxed for 24 hours with continuous stirring. The reaction was cooled to room temperature, the sodium mesylate filtered and the solvent evaporated in vacuo. The residue was dissolved in 300 milliliters of ether and extracted three times with 500 milliliter portions of sodium thiosulfate, twice with 500 milliliter portions of water, and the organic layer dried over anhydrous sodium sulfate. Filtration of the drying agent, evaporation of the ether in vacuo and subsequent silica gel chromatography (hexane:ether 9:1 as eluent) afforded 2.5 grams (87%) of an oily product. 1H-NMR (CDCl3): delta, 0.87 (t, 3H, terminal methyl), 1.2-1.6 [m, 28H, (CH2)14 ], 2.58 (m, 2H, S--CH2), 2.62 (m, 2H, CH--CH2 --S), 3.38(S, 3H, O--CH3), 3.48 (m, 3H, CH--CH2Br).

Workup

  1. customInto a flask equipped with a magnetic stir bar
  2. customdrying tube, and a reflux condenser
  3. filtrationthe sodium mesylate filtered
  4. customthe solvent evaporated in vacuo
  5. dissolutionThe residue was dissolved in 300 milliliters of ether
  6. extractionextracted three times with 500 milliliter portions of sodium thiosulfate
  7. dry with materialtwice with 500 milliliter portions of water, and the organic layer dried over anhydrous sodium sulfate
  8. filtrationFiltration of the drying agent, evaporation of the ether in vacuo and subsequent silica gel chromatography (hexane:ether 9:1 as eluent)

Sources & evidence

ORD record
ord-47b725cb14f146cc881ec4b97dc3371a
Source dataset
uspto-grants-1997_03
Patent number
US05614548

Reaction notes

Loading…