Carbon Dioxide → 2,6-Dichloro-4-methoxynicotinic Acid

Beteiligte Stoffe

Reaktionsschritte

To a solution of 4.0 g (22.5 mmol) 2,6-dichloro-4-methoxy-pyridine in THF (20 ml) was added 10.0 ml (2.47 M in hexane, 24.7 mmol) n-butyllithium at −78° C. After stirring for 1 h at −78° C. excess dry ice was added and the mixture was allowed to warm to RT. Then the mixture was acidified with 6N aqueous hydrochlorid acid to pH 3-4 followed by extraction with EtOAc. The organic layer was dried over Na2SO4 and concentrated in vacuo. Purification of the residue by CC (hexane/EtOAc 4:1) provided 3.5 g (15.8 mmol, 70%) 2,6-dichloro-4-methoxy-pyridine-3-carboxylic acid.

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