Methanol → 1,3-Dioxane, 5-(2-bromoethyl)-2,2-dimethyl-

HRID 1369988Notes

Reaction equation

HRID 1369988 reaction equation
O[CH2:2][CH2:3][CH:4]1[CH2:9][O:8][C:7]([CH3:11])([CH3:10])[O:6][CH2:5]1.C(Br)(Br)(Br)[Br:13].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.CO>CN(C)C=O>[Br:13][CH2:2][CH2:3][CH:4]1[CH2:9][O:8][C:7]([CH3:11])([CH3:10])[O:6][CH2:5]1

Participants

6

Reactant 4

HCID 887MethanolHCID 11205Carbon tetrabromideHCID 11776TriphenylphosphineHCID 118160112-(2,2-Dimethyl-1,3-dioxan-5-yl)ethanol

Product 1

HCID 1789881,3-Dioxane, 5-(2-bromoethyl)-2,2-dimethyl-Yield 40%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To an ice-cooled solution of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxan (1.92 g, 12 mmol) and carbon tetrabromide (7.96 g, 24 mmol) in dimethylformamide (100 ml), triphenylphosphine (6.30 g, 24 mmol) was added and the solution was left at 4° C. overnight. To this solution methanol (20 ml) was added and the solvent was then evaporated under reduced pressure. The residue was purified by column chromatography on silica gel, elutingwith hexane-acetone (12:1) to afford 5-(2-bromoethyl)-2,2-dimethyl-1,3-dioxan as a clear colourless liquid (0.89 g, 40%); νmax (film) 2940, 1370, 1270, 1260, 1200, and 1070 cm−1; δH (CDCl3) 1.42 (6H, s, C(CH3)2), 1.94 (3H, m, CHCH2CH2Br), 3.43 (2H, t, J 7 Hz, CH2Br), and 3.5-4.1 (4H, m, 2×CH2O); (Found: C, 42.84; H, 6.93%. C8H15BrO2 requires: C, 43.07; H, 6.78%. [M−CH3] found 207.0024; C7H12BrO2 requires 207.0021).

Workup

  1. additionwas added
  2. customthe solvent was then evaporated under reduced pressure
  3. customThe residue was purified by column chromatography on silica gel, elutingwith hexane-acetone (12:1)

Sources & evidence

ORD record
ord-2563a984aacd46838fa258cd76920f0a
Source dataset
uspto-grants-2003_06
Patent number
US06579981B1

Reaction notes

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