Diisobutylaluminum hydride → 4,6-Dichloropicolinaldehyde

Participants

Reaction Steps

To a solution of 2-carbomethoxy-4,6-dichloropyridine (206 mg, 1 mmol) in 4 mL of dry toluene at -78° in a 25 mL round bottomed flask fitted with a stirrer bar and rubber septum, prepared by the procedure of D. G. Markees (vide supra) was slowly added 1.33 mL of 1.5M DIBAL (2 equivalents) in toluene. The mixture was stirred at -78° for 45 minutes, then at -50° for 30 minutes. The mixture was quenched with saturated ammonium chloride. After the effervescence ceased, the mixture was poured into 10 mL of water and extracted with 2×20 mL of methylene chloride. The organic layer was dried over anhydrous MgSO4, filtered and the solvent volume reduced. The residue was purifed by flash chromatography (85/15 hexane/ethyl acetate). Recovered 75 mg of product. NMR (CDCl3 200 Mhz): δ 7.59 (d, 1H, J=2 Hz), 7.87 (d, 1H, J=2 Hz), 9.97 (s, 1H).

Provenance & Evidence