Réaction #1833255

Équation de réaction

Methyl 4-amino-3,6-dichloro-5-fluoropicolinate

2-(benzo[d][1,3]dioxol-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane

potassium fluoride

→

title compound

Rendement 68.7%

Methyl 4-amino-6-(benzo[d][1,3]dioxol-4-yl)-3-chloro-5-fluoropicolinate

Rendement 68.7%

Solvants

acetonitrile

water

Conditions de réaction

Traitement

1. 1
   AutreThe reaction mixture was then irradiated in a microwave at 110° C. in a capped vial for 20 min
2. 2
   AutreThe cooled reaction mixture
3. 3
   Autrewas partitioned between ethyl acetate and water
4. 4
   AutreThe organic phase was dried
5. 5
   Concentrationconcentrated onto 1.2 g of silica gel
6. 6
   Lavagethe product was eluted with a 7-60% hexane/ethyl acetate gradient solvent system

Mode opératoire

Methyl 4-amino-3,6-dichloro-5-fluoropicolinate (1.5 g, 6.28 mmol), 2-(benzo[d][1,3]dioxol-4-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (2.024 g, 8.16 mmol), potassium fluoride (0.875 g, 15.06 mmol; Note: Related examples utilize cesium fluoride) and bis(triphenylphosphine)palladium(II)chloride (0.440 g, 0.628 mmol) were combined in acetonitrile (13 mL) and water (4.5 mL). The reaction mixture was then irradiated in a microwave at 110° C. in a capped vial for 20 min, with external IR-sensor temperature monitoring from the side of the vessel. The cooled reaction mixture was partitioned between ethyl acetate and water. The organic phase was dried and concentrated onto 1.2 g of silica gel. This mixture was applied to the top of a silica gel column and the product was eluted with a 7-60% hexane/ethyl acetate gradient solvent system to provide the title compound as a white solid (1.4 g, 68.7%): mp 146-148° C.; 1H NMR (400 MHz, CDCl3) δ 7.16-7.09 (m, 1H), 6.98-6.85 (m, 2H), 6.01 (s, 2H), 4.91 (br s, 2H), 3.98 (s, 3H); ESIMS m/z 325 ([M+H]+).

Source