反应详情

A solution of dimethyl methylphosphonate (2.48 g, 20 mmol) in anhydrous THF (30 mL) was cooled to −78° and treated dropwise with 2.5 M n-BuLi (8.0 mL). After stirring at −78° for 45 min, a solution of ester 6-6 (1.85 g, 5.0 mmol) in THF (10 mL) was added dropwise and the resulting solution stirred for 30 min at −78°, quenched with sat. NH4Cl (25 mL), then extracted with ethyl acetate (3×75 mL). The combined organic extracts were dried (Na2SO4), filtered, and concentrated to afford a yellow oil. Chromatography on silica gel (5% MeOH/CH2Cl2) afforded 6-7 as a yellow oil in 89% yield.

1. stirringthe resulting solution stirred for 30 min at −78°
2. customquenched with sat. NH4Cl (25 mL)
3. extractionextracted with ethyl acetate (3×75 mL)
4. dry with materialThe combined organic extracts were dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customto afford a yellow oil