Citric Acid → 3-Bromopyridine-2-carbaldehyde

Temperatur

60 °C

A suspension of 3-bromo-2-dibromomethyl-pyridine (10.0 g, 30.32 mmole) in morpholine (30.0 mL) was heated to 60° C. for 1 h. The reaction mixture was cooled to rt and diluted with EtOAc (200 mL). The pH was adjusted to 4.0 by adding citric acid (40.0 g). The reaction mixture was then extracted with EtOAc (3×200 mL) and the combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by column chromatography using silica (100-200 mesh) using 3% EtOAc in hexane as eluent to give 3-bromo-pyridine-2-carbaldehyde. 1H-NMR (400 MHz, CDCl3): c 10.23 (s, 1H), 8.74-8.76 (d, 1H), 8.02-8.04 (d, 1H), 7.26-7.38 (t, 1H).

1. temperatureThe reaction mixture was cooled to rt
2. extractionThe reaction mixture was then extracted with EtOAc (3×200 mL)
3. dry with materialthe combined organic layers were dried over Na2SO4
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by column chromatography

ORD-Eintrag

ord-496c42a16afb4affbac7088b8bc558f5

Quelldatensatz

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09096527B2