Sodium hydride → Ethyl 2-(5-nitropyridin-2-YL)acetate

To a suspension of NaH (60% dispersion, 0.900 g, 22.5 mmol) in 40 mL of THF was added malonic acid tert-butyl ester ethyl ester (4.00 mL, 21.1 mmol) and the mixture stirred for 15 min at RT. To this mixture was then added 2-chloro-5-nitro-pyridine (2.56 g, 16.0 mmol) and the reaction stirred for 10 h at RT. The mixture was diluted with 100 mL of EtOAc and washed with NH4Cl (2×100 mL) and brine (100 mL) and dried over Na2SO4 and concentrated in vacuo. The residue was dissolved in DCM (20 mL), TFA (10 mL) was added and the mixture stirred for 2 h at RT. The mixture was concentrated, the residue dissolved in 100 mL of EtOAc and washed with NaHCO3 (2×100 mL) and brine (100 mL) and again dried over Na2SO4 and concentrated in vacuo. The title compound was purified by flash chromatography eluting with 30% EtOAc/hexanes to give 2.35 g (70%) of a light yellow solid. 1H-NMR (CDCl3, 400 MHz): δ 9.38 (d, J=2.6 Hz, 1H), 8.46 (dd, J=8.6, 2.6 Hz, 1H), 7.55 (d, J=8.6 Hz, 1H), 4.22 (q, J=7.1 Hz, 2H), 3.99 (s, 2H), 1.28 (t, J=7.1 Hz, 3H).

1. washwashed with NH4Cl (2×100 mL) and brine (100 mL)
2. dry with materialdried over Na2SO4
3. concentrationconcentrated in vacuo
4. dissolutionThe residue was dissolved in DCM (20 mL)
5. additionTFA (10 mL) was added
6. stirringthe mixture stirred for 2 h at RT
7. concentrationThe mixture was concentrated
8. dissolutionthe residue dissolved in 100 mL of EtOAc
9. washwashed with NaHCO3 (2×100 mL) and brine (100 mL)
10. dry with materialagain dried over Na2SO4
11. concentrationconcentrated in vacuo
12. customThe title compound was purified by flash chromatography
13. washeluting with 30% EtOAc/hexanes

ORDレコード

ord-1c66cfb31112403490926b19f10e2a1a

出典データセット

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08674100B2