反应详情

温度

0 °C

At -20° C., a solution of (-)-B-chlorodiisopinocampheylborane (1.74 g, 1.5 equiv.) in 9 mL of CH2Cl2 was added dropwise to a suspension of the ketone of Step 4 (1.52 g, 3.5 mmol) in 18 mL of CH2Cl2 and the mixture was stirred at 0° C. for an hour and at room temperature for 2 hours. At 0° C., 10% aq. diethanolamine was added and the mixture was stirred at r.t. for 30 min. The product was extracted in EtOAc:THF 1:1, washed with brine, dried over Na2SO4, and concentrated. The oil was dissolved in ether and conc. HCl (5 ml) was added. The precipitated hydrochloride was filtered, washed with ether, and dissolved in THF:0.1 N NaOH. The product was extracted in EtOAc:THF 1:1, washed with brine, dried over Na2SO4 and purified by flash chromatography with EtOAc:toluene 10:90. Yield 1.125 g, 74%.

1. stirringthe mixture was stirred at r.t. for 30 min
2. extractionThe product was extracted in EtOAc:THF 1:1
3. washwashed with brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated
6. dissolutionThe oil was dissolved in ether
7. additionconc. HCl (5 ml) was added
8. filtrationThe precipitated hydrochloride was filtered
9. washwashed with ether
10. dissolutiondissolved in THF
11. extractionThe product was extracted in EtOAc:THF 1:1
12. washwashed with brine
13. dry with materialdried over Na2SO4
14. custompurified by flash chromatography with EtOAc:toluene 10:90