Reaction #8134

Reaction equation

2-Cyclopropyl-methyl-6-(3-fluoro-4-methoxyphenyl)-4-hydroxymethyl-2H-pyridazin-3-one

carbon tetrabromide

pyridine

triphenylphosphine

→

title compound

Yield 69.5%

4-bromomethyl-2-cyclopropylmethyl-6-(3-fluoro-4-methoxyphenyl)-2H-pyridazin-3-one

Yield 69.5%

Solvents

tetrahydrofuran

tetrahydrofuran

Conditions

Workup

1. 1
   Otherfurther stirred overnight
2. 2
   Otherat room temperature
3. 3
   FiltrationInsoluble materials were filtered off
4. 4
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
5. 5
   Otherthe residue was isolated
6. 6
   Otherpurified by column chromatography on silica gel (hexane/ethyl acetate=2/1)

Procedure

2-Cyclopropyl-methyl-6-(3-fluoro-4-methoxyphenyl)-4-hydroxymethyl-2H-pyridazin-3-one (185 mg, 0.61 mmol), carbon tetrabromide (404 mg, 1.2 mmol) and pyridine (48 mg, 0.61 mmol) were dissolved in tetrahydrofuran (3 mL), and under ice-cold stirring, a solution of triphenylphosphine (319 mg, 1.2 mmol) in tetrahydrofuran (3 mL) was added. Under ice cooling, the mixture was stirred for 1 hour, and further stirred overnight at room temperature. Insoluble materials were filtered off, the solvent was distilled off under reduced pressure, and the residue was isolated and purified by column chromatography on silica gel (hexane/ethyl acetate=2/1) to yield the title compound as a yellow powder (yield: 155 mg, 69.5%).

Source