6-Methoxypyridine-3-carbaldehyde → 5-Ethenyl-2-methoxypyridine

Participants

Reaction Steps

A suspension of triphenylmethylphosphonium bromide (31.2 g, 0.0875 mol) in THF (150 mL) at −78° C. under an atmosphere of nitrogen was added 2.5 M n-BuLi (38.0 mL, 0.0948 mol) in hexane during a period of 30 min. The reaction was warmed to room temperature to give a deep red ylide solution. To the ylide solution, cooled in ice, was introduced 6-methoxynicotinaldehyde (10.0 g, 0.0729 mol) in THF (30 mL). The reaction was allowed to reach room temperature and stirred at rt for 3 h. Then the result suspension was heated to 60° C. over 30 minutes and heated at 60° C. for 1 hour. After cooling, the reaction was diluted with water (500 mL). The product was extracted into ethyl ether, washed with brine, dried (MgSO4), and concentrated. The residue was purified with silica gel column (0-40% EtOAc/hexane) to give a light yellow oil. LC-MS: 136.0 [M+1]+;

Provenance & Evidence