Réaction #709902

Équation de réaction

sodium

ammonia

dibromoethylphenyl bicyclooctane

tetrahydrofuran

sodium

ammonia

→

1-(4-ethynylphenyl)bicyclooctane

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONthe addition the blue color
2. 2
   Autreto evaporate overnight
3. 3
   Autrethe residue was partitioned between ether and ice/water
4. 4
   AutreThe organic layer was separated
5. 5
   Séchagedried over K2CO3
6. 6
   Autreevaporated

Mode opératoire

Small pieces of sodium were added to liquid ammonia until a blue color persisted. Ferric nitrate (100 mg) was added and the solution was stirred. When the solution turned colorless, sodium (6 g) was added in small pieces. After about 30 to 35 minutes following the addition the blue color disappeared and a solution of the above dibromoethylphenyl bicyclooctane in tetrahydrofuran was added to the solution. The ammonia was allowed to evaporate overnight and the residue was partitioned between ether and ice/water. The organic layer was separated, dried over K2CO3 and evaporated to leave crude 1-(4-ethynylphenyl)bicyclooctane. This was purified by chromatography on alumina (made basic with NH3) and elution with dichloromethanehexane (1:4) and recrystallization from hexanedichloromethane. The compound was characterized by NMR (300 MHz, CDCl3): δ 0.9 (9H, s, (CH3)3C), 3.05 (1H, s, C≡CH), 4.15 (6H, s, (CH2O)3), 7.45 (2H, d, aromatic), 7.55 (2H, d, aromatic). The compound was also characterized by mass spectrometry (M+ 272) and was found to have a melting point of 167°-168 C.

Source