Ethyl Bromide → HCID 19028316, compound

HRID 2257224Notes

Reaction equation

HRID 2257224 reaction equation
[Mg].BrCC.[CH2:5]([OH:9])[CH2:6][C:7]#[CH:8].Br[CH2:11][C:12]#[C:13][CH2:14][C:15]#[C:16][CH2:17][CH2:18][CH2:19][CH2:20][CH3:21]>O1CCCC1>[CH2:5]([OH:9])[CH2:6][C:7]#[C:8][CH2:11][C:12]#[C:13][CH2:14][C:15]#[C:16][CH2:17][CH2:18][CH2:19][CH2:20][CH3:21]

Participants

6

Reactant 4

HCID 6332Ethyl BromideHCID 135663-Butyn-1-OLHCID 5462224MagnesiumHCID 11831144HCID 11831144, compound

Product 1

HCID 19028316HCID 19028316, compoundYield 72.3%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent4×

Procedure

In a 1 L three-necked, flame-dried round bottom flask fitted with a reflux condenser and a rubber septum was placed 3.86 g (159 mmol) of magnesium in 250 mL of anhydrous tetrahydrofuran. Bromoethane (17.3 g; 1586 mmol) in 250 mL anhydrous tetrahydrofuran was added dropwise, under argon, and the reflux rate was controlled with the aid of an ice-water bath. The mixture was heated to reflux and stirred for 1 hour. 3-Butyn-1-ol (5.56 g, 79.3 mmol), dissolved in 150 mL of anhydrous tetrahydrofuran, was slowly added dropwise with stirring (2 hours). Following addition, the reaction was heated to reflux. After stirring for 90 minutes, 0.5 g (2.63 mmol) of cuprous (I) iodide was added. After 75 minutes 9.0 g (39.65 mmol) of 1-bromo-2,5-undecadiyne dissolved in 150 mL of anhydrous tetrahydrofuran was added. The mixture was heated at reflux for 12 h and an additional 0.25 g (1.32 mmol) of cuprous (I) iodide was added. The mixture was heated at reflux for 7 hours, cooled and quenched by addition of 400 mL of ice-water saturated with ammonium chloride. After filtration (Celite), the filtrate was extracted with 3×400 mL of ether. The ether layers were washed with 2×300 mL of saturated ammonium chloride solution, 3×200 mL of water, 250 mL of brine, dried (Na2SO4), and concentrated in vacuo to yield 6.2 g of yellow-brown oil. The residue was partially purified by crystallization (petroleum ether) at -20° C. to produce 5.75 g (75%) of an unstable yellow oil (room temperature) which was utilized immediately in the next reaction. IR (neat,cm-1) 3365, 2956, 2933, 2225; 1H NMR (CDCl3) δ 3.70 (t, J=6.2 Hz, 2H), 3.17-3.13 (m, 4H), 2.45 (dt, J=1.5, 5.9, 12.0 Hz, 2H), 2.15 (dt, J=2.1, 6.9, 13.9 Hz, 2H), 1.68 (br, 1H), 1.55-1.43 (m, 2H), 1.43-1.26 (m, 4H), 0.89 (t, J=6.9 Hz, 3H); HRMS calculated for C15H20O (M+) 216.1514, found 216.1519.

Workup

  1. customIn a 1 L three-necked, flame-dried round bottom flask
  2. customfitted with a reflux condenser
  3. customthe reflux rate was controlled with the aid of an ice-water bath
  4. temperatureThe mixture was heated
  5. temperatureto reflux
  6. additionwas slowly added dropwise
  7. stirringwith stirring (2 hours)
  8. additionaddition
  9. temperaturethe reaction was heated to reflux
  10. stirringAfter stirring for 90 minutes
  11. additionwas added
  12. temperatureThe mixture was heated
  13. temperatureat reflux for 12 h
  14. temperatureThe mixture was heated
  15. temperatureat reflux for 7 hours
  16. temperaturecooled
  17. customquenched by addition of 400 mL of ice-water saturated with ammonium chloride
  18. filtrationAfter filtration (Celite)
  19. extractionthe filtrate was extracted with 3×400 mL of ether
  20. washThe ether layers were washed with 2×300 mL of saturated ammonium chloride solution, 3×200 mL of water, 250 mL of brine
  21. dry with materialdried (Na2SO4)
  22. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-0aea14e26bda407e92b4b801b645cd63
Source dataset
uspto-grants-1997_08
Patent number
US05656662

Reaction notes

Loading…