反应详情

A solution of diisobutylaluminum hydride 120 ml. 120 mmol, 1.0M in THF) was added to a solution of the product of STEP 2 (11.6 g, 38.7 mmol) in 100 ml THF at 0° C. over 20 min. After 1 h, the reaction was diluted with 25 ml ethyl acetate and quenched with 75 ml H2O. The resulting mixture was filtered through a short column of Celite®, and washed with ethyl acetate. Filtrate was extracted with ethyl acetate (3×100 ml). The combined organic layer was washed with brine, dried with MgSO4, and concentrated. The residue was purified by chromatography (on silica gel, ethyl acetate) to give a pale brown liquid in 4.1 g. NMR spectra of the product were consistent for the proposed structure.

1. customquenched with 75 ml H2O
2. filtrationThe resulting mixture was filtered through a short column of Celite®
3. washwashed with ethyl acetate
4. extractionFiltrate was extracted with ethyl acetate (3×100 ml)
5. washThe combined organic layer was washed with brine
6. dry with materialdried with MgSO4
7. concentrationconcentrated
8. customThe residue was purified by chromatography (on silica gel, ethyl acetate)
9. customto give a pale brown liquid in 4.1 g