تفاعل #2200595

معادلة التفاعل

methyl 4-amino-3,6-dichloro-5-fluoropyridine-2-carboxylate

tributyl(vinyl)tin

cesium fluoride

→

methyl 4-amino-3-chloro-5-fluoro-6-vinylpyridine-2-carboxylate

المردود 67.3%

المذيبات

dimethylformamide

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةAfter cooling
2. 2
   تركيزthe mixture was concentrated
3. 3
   ترشيحfiltered through a silica gel plug
4. 4
   أخرىThe solvents were removed
5. 5
   أخرىthe crude product was purified by column chromatography (50% ethyl acetate in hexane)

الإجراء التجريبي

A solution of methyl 4-amino-3,6-dichloro-5-fluoropyridine-2-carboxylate (8.00 g, 33.0 mmol), tributyl(vinyl)tin (13.27 g, 42.0 mmol) and cesium fluoride (11.19 g, 73.6 mmol) in dimethylformamide (250 mL) was sparged with nitrogen for 15 minutes. Dichlorobis(triphenylphosphine)palladium (II) (1.17 g, 1.6 mmol) was then added and the mixture was heated at 90° C. overnight. After cooling, the mixture was concentrated, taken up into ethyl acetate and filtered through a silica gel plug. The solvents were removed and the crude product was purified by column chromatography (50% ethyl acetate in hexane) to give methyl 4-amino-3-chloro-5-fluoro-6-vinylpyridine-2-carboxylate (5.13 g, 22.2 mmol), mp 68-71° C.

المصدر