Reaktion #2343209

Reaktionsgleichung

1-benzyloxycarbonyl-4-piperidone

hexane ethyl acetate

tert-butyl lithium

anisole

→

1-Benzyloxycarbonyl-4-hydroxy-4-(2-methoxyphenyl)piperidine

Lösungsmittel

water

tetrahydrofuran

pentane

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe resulting reaction mixture
2. 2
   TemperaturThe reaction mixture was cooled back to -78° C.
3. 3
   TemperaturThe reaction mixture was warmed to -15° C.
4. 4
   workup.STIRRINGstirred for 1 hour before it
5. 5
   Sonstigeto reach ambient temperature
6. 6
   workup.STIRRINGstirred for 72 hours
7. 7
   Extraktionextracted several times with ethyl acetate
8. 8
   SonstigeThe combined organic layers were dried
9. 9
   Sonstigeevaporated
10. 10
    Sonstigeto afford the crude product
11. 11
    SonstigeThis material was used in the next step without further purification

Vorschrift

A solution of anisole (2.19 g) in tetrahydrofuran (50 mL) was cooled to -78° C. and treated with tert-butyl lithium (12 mL of a 1.7M solution in pentane). The resulting reaction mixture was warmed to -15° C. and stirred for 45 minutes. The reaction mixture was cooled back to -78° C. and treated with a solution of 1-benzyloxycarbonyl-4-piperidone (4.67 g) in tetrahydrofuran (5 mL). The reaction mixture was warmed to -15° C. and stirred for 1 hour before it was allowed to reach ambient temperature and stirred for 72 hours. The reaction mixture was diluted with water, and extracted several times with ethyl acetate. The combined organic layers were dried and evaporated to afford the crude product. Chromatography, with hexane:ethyl acetate (2:1) as the eluent, gave a mixture of the alcohol and starting material (2.98 g); NMR (CDCl3): 1.95-2.04 (m, 4), 2.9 (broad, 2), 3.90 (s, 3), 5.15 (s, 2), 6.93-6.99 (m, 2), 7.21-7.36 (m, 7); MS: m/z=342(M+1). This material was used in the next step without further purification.

Quelle