反应详情

The product of Example 61A (62.3 g, 0.167 mol), NaBH(OAc)3 (150.0 g, 0.708 mol), and powdered 4A molecular sieves (133.0 g) in toluene (730 mL) in a 3-neck round bottom flask equipped with a mechanical stirrer, thermometer and addition funnel at 0° C. was treated with acetic acid (191 mL, 3.30 mol) dropwise. After the addition was complete, the ice-bath was removed and the mixture was stirred for 20 hours, filtered and the filtrate concentrated under reduced pressure. The residue was dissolved in ethyl acetate (1000 mL) and quenched by slow addition of saturated aqueous NaHCO3. The layers were separated and the aqueous layer was extracted with ethyl acetate. The combined organics were dried over Na2SO4, filtered and the filtrate concentrated under reduced pressure to provide the product as a 1:1.5 mixture of the two (cis) isomers (60.0 g, 0.159 mol, 94% yield). MS (DCI/NH3) m/z 377 (M+H)+.

1. customequipped with a mechanical stirrer
2. additionthermometer and addition funnel at 0° C.
3. additionAfter the addition
4. customthe ice-bath was removed
5. filtrationfiltered
6. concentrationthe filtrate concentrated under reduced pressure
7. dissolutionThe residue was dissolved in ethyl acetate (1000 mL)
8. customquenched by slow addition of saturated aqueous NaHCO3
9. customThe layers were separated
10. extractionthe aqueous layer was extracted with ethyl acetate
11. dry with materialThe combined organics were dried over Na2SO4
12. filtrationfiltered
13. concentrationthe filtrate concentrated under reduced pressure
14. customto provide the product
15. additionas a 1:1.5 mixture of the two (cis) isomers (60.0 g, 0.159 mol, 94% yield)