Reaktion #95467

Reaktionsgleichung

phosphorous tribromide

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

→

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

Lösungsmittel

ether

ether

Reaktionsbedingungen

Aufarbeitung

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

Vorschrift

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.

Quelle