Reaktion #2075734

Reaktionsgleichung

2-Chloro-6-methoxy-7-methyl-7H-purine

2-(4-chloro-2-fluoro-3-methoxyphenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane

cesium fluoride

→

title compound

Ausbeute 67.0%

2-(4-Chloro-2-fluoro-3-methoxyphenyl)-6-methoxy-7-methyl-7H-purine

Ausbeute 67.0%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigedry
2. 2
   Temperaturheated to reflux
3. 3
   Temperaturthe mixture was cooled
4. 4
   workup.ADDITIONmixed with ethyl acetate and water
5. 5
   WaschenThe organic phase was washed with water, brine
6. 6
   Sonstigedried
7. 7
   Sonstigeevaporated under vacuum
8. 8
   SonstigeThe residue was purified by flash chromatography on silica gel with 20% ethyl acetaete/hexane

Vorschrift

2-Chloro-6-methoxy-7-methyl-7H-purine (1.2 g, 6.0 mmol, see Monatshefte fuer Chemie (1985), 116(3), 341-51 for preparation), 2-(4-chloro-2-fluoro-3-methoxyphenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (2.1 g, 8.6 mmol), Pd(PPh3)2Cl2 (300 mg, 0.42 mmol) and cesium fluoride (1.6 g, 11 mmol) were combined in 10 mL dry, deaerated acetonitrile and heated to reflux. After 2 h, the mixture was cooled and mixed with ethyl acetate and water. The organic phase was washed with water, brine, dried and evaporated under vacuum. The residue was purified by flash chromatography on silica gel with 20% ethyl acetaete/hexane to give the title compound (1.3 g, 67% yield: mp 191-192° C.: 1H NMR (CDCl3) δ 8.0 (s, 1H), 7.90 (dd, 1H), 7.22 (dd, 1H), 4.22 (s, 3H), 4.08 (s, 3H), 4.02 (s, 3H).

Quelle