Réaction #42725

Équation de réaction

methanol

8-Benzyloxy 5-(2-bromoacetyl)-1H-quinolin-2-one

tetrahydrofuran

Borane

→

title compound

Rendement 81.0%

8-Benzyloxy-5-((R)-2-bromo-1-hydroxyethyl)-1H-quinolin-2-one

Rendement 81.0%

Solvants

toluene

Conditions de réaction

Traitement

1. 1
   ConcentrationThe mixture was concentrated under vacuum
2. 2
   workup.DISSOLUTIONthe residue was dissolved
3. 3
   Filtrationfiltered while hot and
4. 4
   Températurethen cooled to room temperature
5. 5
   FiltrationThe crystals were filtered
6. 6
   Lavagewashed with acetonitrile
7. 7
   Autredried under vacuum

Mode opératoire

8-Benzyloxy 5-(2-bromoacetyl)-1H-quinolin-2-one (90.0 g, 243 mmol) was placed under nitrogen and tetrahydrofuran (900 mL) was added followed by the catalyst described above (1.8 M in toluene, 15 mL, 27 mmol). The suspension was cooled to −10±5° C. in an ice/isopropanol bath. Borane (1.0 M in THF, 294 mL, 294 mmol) was added over 4 h. The reaction was then stirred an additional 45 min at −10° C. and then methanol (250 mL) was added slowly. The mixture was concentrated under vacuum and the residue was dissolved in boiling acetonitrile (1.3 L), filtered while hot and then cooled to room temperature. The crystals were filtered, washed with acetonitrile and dried under vacuum to give the title compound (72.5 g, 196 mmol, 81% yield, 95% ee, 95% pure by HPLC).

Source