Reacción #95467

Ecuación de reacción

phosphorous tribromide

(Z,Z)-5,8-tetradecadien-2-yn-1-ol

→

(Z,Z)-1-bromo-5,8-tetradecadien-2-yne

Disolventes

ether

ether

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction mixture was heated
2. 2
   Temperaturaunder reflux for 2.5 h
3. 3
   workup.ADDITIONpoured onto ice-water
4. 4
   ExtracciónIt was extracted three times with ether
5. 5
   LavadoThe combined ether extracts were washed with dilute aqueous sodium bicarbonate solution, water
6. 6
   Secadodried over Na2SO4
7. 7
   Concentraciónconcentrated in vacuo
8. 8
   workup.DISTILLATIONEvaporative distillation of the crude product at 145°-148° C./0.15 mm

Procedimiento

A solution of phosphorous tribromide (0.47 g, 1.73 mmol) in absolute ether (0.5 ml) was added dropwise during five minutes to a mixture of (Z,Z)-5,8-tetradecadien-2-yn-1-ol (1.03 g, 5 mmol), and dry pyridine (14 mg, 0.18 mmol) in 8 ml of absolute ether. The reaction mixture was heated under reflux for 2.5 h, cooled to 23° C., then poured onto ice-water. It was extracted three times with ether. The combined ether extracts were washed with dilute aqueous sodium bicarbonate solution, water, dried over Na2SO4 and concentrated in vacuo. Evaporative distillation of the crude product at 145°-148° C./0.15 mm afforded 1.1 g (80.5%) of (Z,Z)-1-bromo-5,8-tetradecadien-2-yne as a pale yellow oil.

Fuente