反应详情

温度

-78 °C

A solution of 3,6-dihydro-4-[4-[[(phenylmethoxy)carbonyl]amino]phenyl]-1(2H)-pyridinecarboxylic acid phenylmethyl ester (EXAMPLE 17, Step 2, 0.500 g) in dry tetrahydrofuran (5.7 mL) at −78° C. under N2 is treated with n-butyllithium (0.73 mL, 1.6M in hexanes) dropwise over five minutes. The resulting mixture is stirred at −78° C. for 45 minutes and is then treated with (R)-(−)-glycidyl butyrate dropwise. The resulting solution is allowed to warm to ambient temperature over approximately 45 minutes and is stirred for an additional 20 hours, after which the reaction is quenched with saturated aqueous ammonium chloride (10 mL), diluted with water (20 mL) and extracted with ethyl acetate (2×15 mL). The combined organic phase is washed with saline (10 mL), dried over anhydrous magnesium sulfate and concentrated under reduced pressure to give the crude product which is chromatographed on silica gel (230-400 mesh, 40 g), eluting with methanol/methylene chloride (1/99). Pooling and concentration of those fractions with an Rf=0.37 by TLC (methanol/chloroform, 5/95) gives the title compound, mp 131.5-133.5° C.

1. temperatureto warm to ambient temperature over approximately 45 minutes
2. stirringis stirred for an additional 20 hours
3. customafter which the reaction is quenched with saturated aqueous ammonium chloride (10 mL)
4. additiondiluted with water (20 mL)
5. extractionextracted with ethyl acetate (2×15 mL)
6. washThe combined organic phase is washed with saline (10 mL)
7. dry with materialdried over anhydrous magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. customto give the crude product which
10. customis chromatographed on silica gel (230-400 mesh, 40 g)
11. washeluting with methanol/methylene chloride (1/99)