(5,6-Dichloropyridin-3-yl)methanol → 5,6-Dichloropyridine-3-carbaldehyde

Participants

Reaction Steps

To a solution of (5,6-Dichloro-pyridin-3-yl)-methanol (1.8 g, 10 mmol) in CH2Cl2 (20 ml) was added manganese dioxide (4.4 g, 50 mmol). The reaction was stirred for 16 h after which time it was filtered through a pad of Hyflo and a fresh portion of manganese dioxide (1.8 g, 20 mmol) added and the reaction stirred for a further 4 h. The manganese dioxide was removed by filtration through Hyflo and the reaction concentrated affording crude 5,6-dichloro-pyridine-3-carbaldehyde (1.4 g, 81%). This was then dissolved in toluene (20 ml) and (methoxycarbonylmethylene)triphenylphosphorane (4.1 g, 12 mmol) added and the mixture heated to reflux for 1 h after which time the mixture was diluted with CH2Cl2, silica gel added and the mixture concentrated to dryness. The absorbed product was then purified by flash column chromatography (EtOAc:Heptane 1:1) furnishing the title compound (1.5 g, 81%) as a white solid.

Provenance & Evidence