N,N,N',N'-Tetramethylethylenediamine → HCID 67423670, compound

Temperature

-55 °C

To a cold (−78° C.) solution of N,N,N′,N′-tetramethylethylenediamine (TMEDA) (4.06 mL, 26.9 mmol) in dry THF (50 mL) under an atmosphere of Ar was added n-BuLi (2.5 M in hexanes, 10.7 mL, 26.9 mmol). 2-Bromo-3-methylpyridine (3.0 mL, 26.9 mmol) was added dropwise and the temperature was raised to −55° C. for 30 minutes. The reaction mixture turned red. It was then cooled to −78° C. and dimethyl glutarate (1.65 mL, 11.2 mmol) was added. The reaction mixture was stirred at −78° C. for 1 h. Water (200 mL) was added and the mixture was extracted with CH2Cl2 (3 times 200 mL). The combined organic extracts were washed with brine (200 mL), were dried over mgSO4, filtered and concentrated. The crude material was purified by flash column chromatography on silica gel (1:1 EtOAc:hexanes) to provide 1.5 g (48%) of 1,5-bis-(3-methyl-pyridin-2-yl)-pentane-1,5-dione as a white solid. 1H NMR(CDCl3) δ 2.00 (p, 2H, J=7.5 Hz), 2.44 (s, 6H), 3.19 (t, 4H, J=7.5 Hz), 7.18 (dd, 2H, J=7.8, 4.2 Hz), 7.43 (d, 2H, J=7.8 Hz), 8.33 (d, 2H, J=4.2 Hz).

1. temperatureIt was then cooled to −78° C.
2. extractionthe mixture was extracted with CH2Cl2 (3 times 200 mL)
3. washThe combined organic extracts were washed with brine (200 mL)
4. customwere dried over mgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe crude material was purified by flash column chromatography on silica gel (1:1 EtOAc:hexanes)

ORD record

ord-84534fa8c924463e9230000d7f720f19

Source dataset

uspto-grants-2009_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07550484B2