Dimethylformamide → 2-([2-Tert-butyldimethylsiloxy]ethoxy)-4-nitrobenzaldehyde

To a stirred suspension of 2-hydroxy-4-nitrobenzaldehyde (0.500 g, 2.992 mmol) and anhydrous potassium carbonate (0.621 g, 4.488 mmol) in dry MeCN (20 ml) at room temperature was added 2-bromo-1-tert-butyldimethylsiloxyethane (83%, 1.293 g, 4.488 mmol), and the reaction mixture was heated under reflux for 40 min which resulted in the appearance of a thick, dark red precipitate. The reaction mixture was left to cool to room temperature and dry DMF (10 ml) was added. The reaction mixture was heated at 100° C. for 4 h and on cooling was added to water (250 ml) and extracted with EtOAc (3×80 ml). The combined organic extracts were washed with water (3×100 ml), brine (100 ml) and dried (Na2SO4) and the solvent was removed under reduced pressure to give a light brown solid which was purified by flash chromatography (2:1 Hexane/Et2O). Recrystallisation from hexane gave the title compound (0.621 g, 64%) as pale yellow crystals.

1. temperaturethe reaction mixture was heated
2. temperatureunder reflux for 40 min which
3. customresulted in the appearance of a thick, dark red precipitate
4. waitThe reaction mixture was left
5. temperatureThe reaction mixture was heated at 100° C. for 4 h
6. temperatureon cooling
7. extractionextracted with EtOAc (3×80 ml)
8. washThe combined organic extracts were washed with water (3×100 ml), brine (100 ml)
9. dry with materialdried (Na2SO4)
10. customthe solvent was removed under reduced pressure
11. customto give a light brown solid which
12. customwas purified by flash chromatography (2:1 Hexane/Et2O)
13. customRecrystallisation from hexane

ORD-Eintrag

ord-80c3231a40df4fb5ac0228c52f034efa

Quelldatensatz

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08895313B2