Ethyl chloroformate → Ethyl 3-(pyridin-2-yl)prop-2-ynoate

Temperatur

-75 °C

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]+.

1. stirringthe reaction mixture was stirred at −75° C. for 1 h
2. extractionextracted with ethyl acetate
3. washthe combined organic extracts washed with brine
4. dry with materialdried over sodium sulphate
5. filtrationfiltered
6. customevaporated
7. customPurification by chromatography (silica, 0 to 50% ethyl acetate in heptane)

ORD-Eintrag

ord-ff321238326340f5b3f34bbffc913929

Quelldatensatz

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08742097B2