Ethyl Propionate → (S)-2-(2-Oxo-2H-pyrid-1-yl)-propionic acid ethyl ester

A stirred solution of 1H-Pyridin-2-one (500 mg, 5.26 mmol) in anhydrous THF (50 ml) at room temperature was treated portionwise with 60% NaH (231 mg, 5.78 mmol). The reaction mixture was kept for 10 min then added over 5 min to a solution of (R)-2-trifluoromethanesulfonyloxy)-propionic acid ethyl ester (1315 mg, 5.26 mmol) in anhydrous THF (2.5 ml) at room temperature. The resulting mixture was stirred for 2 h, then concentrated. The residue was dissolved in ethyl acetate, and the resulting solution was washed with ice cold dilute HCl. The organic layer was removed and the aqueous layer re-extracted with ethyl acetate. The combined organic extracts were dried (MgSO4), filtered and concentrated. The residue was purified by flash chromatography (20% up to 80% ethyl acetate in hexane) to afford the title compound as a yellow oil (480 mg, 46%): [α]27D=−56.4° (c=0.275, CH2Cl2); 1H NMR (400 MHz CDCl3) δ 1.3 (3H, t), 1.65 (3H, d), 4.2 (2H, q), 5.6 (1H, q), 6.2 (1H, t), 6.4 (1H, d), 7.2-7.3 (2H, m).

1. concentrationconcentrated
2. dissolutionThe residue was dissolved in ethyl acetate
3. washthe resulting solution was washed with ice cold dilute HCl
4. customThe organic layer was removed
5. extractionthe aqueous layer re-extracted with ethyl acetate
6. dry with materialThe combined organic extracts were dried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue was purified by flash chromatography (20% up to 80% ethyl acetate in hexane)

ORD record

ord-74470b41c3c843c9b927d6d476749849

Source dataset

uspto-grants-2012_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08288537B2