反应详情

8-Cyanomethyl-1,4-dioxa-spiro[4.5]decane-8-carboxylic acid ethyl ester (525 mg, obtained in example 133, step 2) was dissolved in methanol (10 mL) and acetic acid (5 mL). Platinum (IV) oxide (235 mg) was added and an atmosphere of hydrogen was introduced at r.t. The mixture was stirred under hydrogen at room temperature for 18 hours. The reaction was filtered over dicalite speed plus (Acros Organics) and the filtrate was concentrated in vacuo. The residue was poured into ice/water and was basified with 2M aqueous NaOH solution. The aqueous layer was extracted two times with ethyl acetate. The combined organic layers were washed with brine, dried over Na2SO4, filtered and the solvent was evaporated. The residue was purified by flash chromatography (silica gel, gradient of heptane in ethyl acetate) to give the title compound as a colorless solid (169 mg, 39%). MS (m/e): 212.2 [MH+].

1. filtrationThe reaction was filtered over dicalite speed plus (Acros Organics)
2. concentrationthe filtrate was concentrated in vacuo
3. additionThe residue was poured into ice/water
4. extractionThe aqueous layer was extracted two times with ethyl acetate
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. customthe solvent was evaporated
9. customThe residue was purified by flash chromatography (silica gel, gradient of heptane in ethyl acetate)