反应详情

A solution of 2,6-dichloro-4-nitrophenol (5.0 g, 24.0 mmol) in 10 ml of tetrahydrofuran is added dropwise to a suspension of sodium hydride (1.33 g, 50% NaH, 27.6 mmol) in 20 ml of THF. After the addition, stirring is continued for 1 hour at RT and is the mixture is then added dropwise to a solution of phosgene (14.0 g) in 50 ml of methylene chloride at -10°. The mixture is allowed to warm to RT and is purged with N2 to remove excess phosgene. The solvent is stripped and the residue is taken into methylene chloride. The precipitated sodium chloride is filtered and the filtrate is concentrated to give 2,6-dichloro-4-nitrophenyl chloroformate.

1. additionAfter the addition
2. customis purged with N2
3. customto remove excess phosgene
4. filtrationThe precipitated sodium chloride is filtered
5. concentrationthe filtrate is concentrated