Reaction #82931

Reaction equation

4-Bromo-5-methoxy-3-[3-(trifluoromethyl)phenyl]pyridazine

vinyltributyltin

→

4-ethenyl-5-methoxy-3-[3-(trifluoromethyl) phenyl]pyridazine

Yield 42.0%

Solvents

DMF

Conditions

Workup

1. 1
   TemperatureThe reaction was then cooled
2. 2
   Otherpartitioned between aqueous KF and ethyl acetate
3. 3
   ExtractionThe KF solution was extracted with additional ethyl acetate
4. 4
   WashThe organic layers were washed with brine
5. 5
   Dryingdried (MgSO4)
6. 6
   Filtrationfiltered through silica gel
7. 7
   Otherevaporated in vacuo
8. 8
   OtherThe crude oil was then chromatographed on a Prep-500

Procedure

4-Bromo-5-methoxy-3-[3-(trifluoromethyl)phenyl]pyridazine (1.0 g, 0.003 mole, Compound No. 57), vinyltributyltin (1.1 g, 0.0034 mole) and trans-benzyl(chloro)bis-(triphenylphosphine)-palladium(II) (20 mg) were heated to 110° C. in DMF (50 mL) under N2 for 4 h. The reaction was then cooled and partitioned between aqueous KF and ethyl acetate. The KF solution was extracted with additional ethyl acetate. The organic layers were washed with brine, dried (MgSO4), filtered through silica gel and then evaporated in vacuo. The crude oil was then chromatographed on a Prep-500 to give 4-ethenyl-5-methoxy-3-[3-(trifluoromethyl) phenyl]pyridazine (0.35 g, 42% yield, Compound No. 55) as a light brown solid.

Source