Réaction #6004

Équation de réaction

3-bromopyridine

n-butyllithium

hexane

(±)-2-methoxycyclohexanone

→

(±)-2-methoxy-1-(pyrid-3-yl)cyclohexanol

Rendement 80.0%

Solvants

ether

diethyl ether

ether

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONpoured onto ice (150 g)
2. 2
   ExtractionThe mixture was extracted with ether (2×50 ml)
3. 3
   Extractionthe combined organic extracts were extracted with 1N hydrochloric acid (50 ml)
4. 4
   ExtractionThis aqueous extract
5. 5
   Lavagewas washed with ether (20 ml)
6. 6
   workup.ADDITIONtreated with 2M sodium hydroxide solution (25 ml)
7. 7
   Extractionextracted with ether (3×100 ml)
8. 8
   Lavagewashed with brine
9. 9
   Séchagethen dried over anhydrous sodium sulphate
10. 10
    ConcentrationConcentration in vacuo

Mode opératoire

To a solution of 2.5M n-butyllithium in hexane (13.2 ml, 33 mmol) at -78° C. was added diethyl ether (15 ml) followed by a solution of 3-bromopyridine (4.7 g, 30 mmol) in ether (90 ml) over a period of 10 minutes. After 1 hour at -78° C. a solution of (±)-2-methoxycyclohexanone (3.84 g, 30 mmol) in ether (20 ml) was added dropwise during 10 minutes. After 2 hours at -78° C. and 30 minutes at 0° C. the reaction mixture was warmed to 20° C. and then poured onto ice (150 g). The mixture was extracted with ether (2×50 ml) and then the combined organic extracts were extracted with 1N hydrochloric acid (50 ml). This aqueous extract was washed with ether (20 ml) and then treated with 2M sodium hydroxide solution (25 ml) and extracted with ether (3×100 ml). The organic extracts were combined, washed with brine then dried over anhydrous sodium sulphate. Concentration in vacuo afforded (±)-2-methoxy-1-(pyrid-3-yl)cyclohexanol (5.0 g, 24 mmol) as a 4:1 mixture of cis and trans isomers;

Source