Ethyl isobutyrate → HCID 59776349, compound

Temperature

-78 °C

To a solution of ethyl isobutyrate (530 μl; 4.08 mmol) in THF (5 mL) was added lithium bis(trimethylsilyl)amide (7.30 mL; solution 1.00 M in THF; 7.30 mmol) at −78° C. The mixture was removed from the cooling bath and stirred for 30 min. It was then cannulated over a suspension of 4-(4-chlorobut-2-yn-1-yl)morpholine hydrochloride (prepared as described by Gomez et al., 1997 Tetrahedron, 53(50), 17201-17210; 714 mg; 3.40 mmol) in THF (5 mL) maintained at −78° C. The reaction mixture was left in the cooling bath and allowed to warm up to rt. After 3 h, it was quenched with water and extracted twice with EtOAc. Combined organic phases were washed with brine, dried over magnesium sulfate, filtrated and concentrated. Purification of the crude by flash chromatography on silica (gradient DCM:MeOH 100:0 to 90:10) gave the title compound as a colorless oil (600 mg, 70% yield). 1H NMR (DMSO-d6) δ: 4.11 (qd, J=7.1 Hz, 2H), 4.14 (m, 4H), 3.31 (t, J=2.1Hz, 0.6H), 3.25 (m, 1.4H), 2.52 (m, 4H), 2.43 (t, J=2.3 Hz, 2H), 1.25 (s, 6H), 1.23 (t, J=7.0 Hz, 3H).

1. customThe mixture was removed from the cooling bath
2. waitThe reaction mixture was left in the cooling bath
3. temperatureto warm up to rt
4. waitAfter 3 h
5. customit was quenched with water
6. extractionextracted twice with EtOAc
7. washCombined organic phases were washed with brine
8. dry with materialdried over magnesium sulfate
9. filtrationfiltrated
10. concentrationconcentrated
11. customPurification of the crude by flash chromatography on silica (gradient DCM:MeOH 100:0 to 90:10)

ORD record

ord-13670b5efc6647129640c51309638f5c

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07973039B2