Reaktion #489554

Reaktionsgleichung

ethyl chloroformate

2-ethynyl-pyridine

BuLi

→

title compound

Ausbeute 66.4%

Pyridin-2-yl-propynoic acid ethyl ester

Ausbeute 66.4%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe reaction mixture was stirred at −75° C. for 1 h
2. 2
   Extraktionextracted with ethyl acetate
3. 3
   Waschenthe combined organic extracts washed with brine
4. 4
   Trocknendried over sodium sulphate
5. 5
   Filtrationfiltered
6. 6
   Sonstigeevaporated
7. 7
   SonstigePurification by chromatography (silica, 0 to 50% ethyl acetate in heptane)

Vorschrift

To a solution of 2-ethynyl-pyridine (309 mg, 3 mmol) in THF (6 mL) was added BuLi (1.6 M in hexane, 1.88 mL, 3 mmol) dropwise at −75° C. and the reaction mixture was stirred at −75° C. for 30 min, then ethyl chloroformate (286 μL, 3 mmol) was added dropwise at −75° C. and the reaction mixture was stirred at −75° C. for 1 h. The mixture was then poured into ice water and extracted with ethyl acetate and the combined organic extracts washed with brine, dried over sodium sulphate, filtered and evaporated. Purification by chromatography (silica, 0 to 50% ethyl acetate in heptane) afforded the title compound (349 mg, 66%) as a brown solid. MS: m/e=176.2 [M+H]+.

Quelle