Reaktion #68624

Reaktionsgleichung

5-chloro-2,3-difluoropyridine

potassium phosphate tribasic

1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

X-Phos

→

2,3-difluoro-5-(1-methyl-1H-pyrazol-4-yl)pyridine

Ausbeute 88.5%

Lösungsmittel

H2O

dioxane

—

Hexanes

EtOAc

EtOAc

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe flask was sealed with a septum
2. 2
   Sonstigecap
3. 3
   SonstigeThe resulting mixture was sparged with N2 for 10 min
4. 4
   TemperaturThe solution was cooled to rt
5. 5
   Einengenconcentrated
6. 6
   Sonstigepurified by flash chromatography

Vorschrift

A sealable flask was charged with 5-chloro-2,3-difluoropyridine (1.541 g, 10.3 mmol), palladium(ii) acetate (0.116 g, 0.515 mmol), potassium phosphate tribasic (6.56 g, 30.9 mmol), 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (2.57 g, 12.4 mmol), and X-Phos (0.491 g, 1.03 mmol). The flask was sealed with a septum cap, then dioxane (20 mL) and H2O (2 mL) were added. The resulting mixture was sparged with N2 for 10 min, and then heated at 100° C. for 2 h. The solution was cooled to rt and then concentrated and purified by flash chromatography using eluent 99:1 Hexanes:EtOAc to 60:40 Hexanes:EtOAc gradient to afford 2,3-difluoro-5-(1-methyl-1H-pyrazol-4-yl)pyridine (1.78 g, 88.5% yield) as a colorless film. LRMS (ESI) m/z calcd for C9H7F2N3 (M+H) 197.1. found 197.4.

Quelle