反应详情

温度

0 °C

A solution of 1,4-dioxa-spiro[4.5]decane-8-carboxylic acid ethyl ester (1.0 g, obtained in example 121, step 1) in THF (8 mL) was added dropwise over a period of 10 minutes at −5° C. (ice/methanol bath) to a solution of lithiumdiisopropylamide (2M in THF/heptane/ethyl benzene, 4.67 mL) in THF (12 mL) and the mixture was stirred for 1 hour at 0° C. The reaction mixture was re-cooled to −5° C. and a solution of bromoacetonitrile (0.65 mL, [CAS Reg. No. 590-17-0]) in THF (4 mL) was added dropwise over a period of 10 minutes. The mixture was allowed to warm to RT and stirring was continued for 16 hours. The reaction was poured into ice/water and was acidified with 1M aqueous HCl solution (50 mL). The aqueous layer was extracted two times with ethyl acetate and the combined organic layers were washed with brine, dried over Na2SO4 and filtered. The solvent was evaporated and the residue was purified by flash chromatography (silica gel, gradient of heptane in ethyl acetate) to give the title compound as a brown liquid (528 mg, 45%). MS (m/e): 254.2 [MH+].

1. temperatureThe reaction mixture was re-cooled to −5° C.
2. temperatureto warm to RT
3. stirringstirring
4. waitwas continued for 16 hours
5. extractionThe aqueous layer was extracted two times with ethyl acetate
6. washthe combined organic layers were washed with brine
7. dry with materialdried over Na2SO4
8. filtrationfiltered
9. customThe solvent was evaporated
10. customthe residue was purified by flash chromatography (silica gel, gradient of heptane in ethyl acetate)