Réaction #2320359

Équation de réaction

3-chloro-6,7-dihydro[1,4]dioxino[2,3-c]pyridazine

dimethoxyethane

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product

Rendement 50.0%

3-Ethenyl-6,7-dihydro[1,4]dioxino[2,3-c]pyridazine

Rendement 50.0%

Conditions de réaction

Traitement

1. 1
   Autrewas degassed under argon for 10 min
2. 2
   workup.ADDITIONtetrakis(triphenylphosphine)palladium (0) (2 g), potassium carbonate (10.33 g), triethenylboroxin pyridine complex (11.32 g) and water (55 ml) were added
3. 3
   Températurecooled
4. 4
   Autreevaporated to dryness
5. 5
   workup.ADDITIONThe mixture was treated with aqueous sodium bicarbonate solution
6. 6
   Extractionextracted (5×) with DCM
7. 7
   SéchageExtracts were dried (sodium sulphate)
8. 8
   Autreevaporated
9. 9
   Autrethe residue chromatographed on silica gel (500 g)
10. 10
    Lavageeluting with 0-100% ethyl acetate-hexane

Mode opératoire

A solution of 3-chloro-6,7-dihydro[1,4]dioxino[2,3-c]pyridazine (13.6 g, 0.079 mol) containing ca. 15% of a bromo species in dimethoxyethane (400 ml) was degassed under argon for 10 min then tetrakis(triphenylphosphine)palladium (0) (2 g), potassium carbonate (10.33 g), triethenylboroxin pyridine complex (11.32 g) and water (55 ml) were added. The mixture was heated at 95° C. for 48 h and cooled and evaporated to dryness. The mixture was treated with aqueous sodium bicarbonate solution and extracted (5×) with DCM. Extracts were dried (sodium sulphate), evaporated and the residue chromatographed on silica gel (500 g), eluting with 0-100% ethyl acetate-hexane, affording the product (6.43 g, 50%); [also some impure fractions (1.8 g)]

Source